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See detailThe edge-based strain smoothing method for compressible and nearly incompressible non-linear elasticity for solid mechanics
Lee, Chang-Kye; Mihai, L. Angela; Kerfriden, Pierre et al

E-print/Working paper (in press)

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See detailEquivariant K-homology for hyperbolic reflection groups
Lafont, Jean-Francois; Ortiz, Ivonne; Rahm, Alexander UL et al

E-print/Working paper (in press)

We compute the equivariant K-homology of the classifying space for proper actions, for cocompact 3-dimensional hyperbolic reflection groups. This coincides with the topological K-theory of the reduced C ... [more ▼]

We compute the equivariant K-homology of the classifying space for proper actions, for cocompact 3-dimensional hyperbolic reflection groups. This coincides with the topological K-theory of the reduced C*-algebra associated to the group, via the Baum-Connes conjecture. We show that, for any such reflection group, the associated K-theory groups are torsion-free. This means that we can complete previous computations with rational coefficients to get results with integral coefficients. On the way, we establish an efficient criterion for checking torsion-freeness of K-theory groups, which can be applied far beyond the scope of the present paper. [less ▲]

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See detailThe Farrell--Tate and Bredon homology for PSL_4(Z) and other arithmetic groups
Bui, Anh Tuan; Rahm, Alexander UL; Wendt, Matthias

E-print/Working paper (in press)

We provide some new computations of Farrell--Tate and Bredon (co)homology for arithmetic groups. For calculations of Farrell--Tate or Bredon homology, one needs cell complexes where cell stabilizers fix ... [more ▼]

We provide some new computations of Farrell--Tate and Bredon (co)homology for arithmetic groups. For calculations of Farrell--Tate or Bredon homology, one needs cell complexes where cell stabilizers fix their cells pointwise. We provide an algorithm computing an efficient subdivision of a complex to achieve this rigidity property. Applying this algorithm to available cell complexes for PSL_4(Z) and PGL_3(Z[i]) provides computations of Farrell--Tate cohomology for small primes as well as the Bredon homology for the classifying spaces of proper actions with coefficients in the complex representation ring. On the other hand, to check correctness of the computer calculations, we describe the Farrell--Tate cohomology in some rank-one cases, using Brown's complex and a number-theoretic description of the conjugacy classification of cyclic subgroups. [less ▲]

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See detailOn Farrell-Tate cohomology of SL_2 over S-integers
Rahm, Alexander UL; Wendt, Matthias

E-print/Working paper (in press)

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See detailGenuine Bianchi modular forms of higher level, at varying weight and discriminant
Rahm, Alexander UL; Tsaknias, Panagiotis UL

E-print/Working paper (in press)

Bianchi modular forms are automorphic forms over an imaginary quadratic field, associated to a Bianchi group. Even though modern studies of Bianchi modular forms go back to the mid 1960's, most of the ... [more ▼]

Bianchi modular forms are automorphic forms over an imaginary quadratic field, associated to a Bianchi group. Even though modern studies of Bianchi modular forms go back to the mid 1960's, most of the fundamental problems surrounding their theory are still wide open. Only for certain types of Bianchi modular forms, which we will call "generic", it is possible at present to develop dimension formulas: They are (twists of) those forms which arise from elliptic cuspidal modular forms via the Langlands base-change procedure, or arise from a quadratic extension of the imaginary quadratic field via automorphic induction (so-called CM-forms). The remaining, non-"generic" Bianchi modular forms are what we call "genuine", and they are of interest for an extension of the modularity theorem (formerly the Taniyama-Shimura conjecture, crucial in the proof of Femat's Last Theorem) to imaginary quadratic fields. In a preceding paper by Rahm and Sengun, an extreme paucity of "genuine" cuspidal Bianchi modular forms has been reported, but those and other computations and were restricted to level One. In this paper, we are extending the formulas for the "generic" Bianchi modular forms to deeper levels, and we are able to spot the first, rare instances of "genuine" forms at deeper level and heavier weight. [less ▲]

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See detailYolanda von Vianden und das Yolanda-Epos
Sieburg, Heinz UL

E-print/Working paper (in press)

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See detailEntwicklungen der Trans*-Bewegung in der Bundesrepublik Deutschland
De Silva, Adrian UL

E-print/Working paper (in press)

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See detailOn the Cohomological Crepant Resolution Conjecture for the complexified Bianchi orbifolds
Perroni, Fabio; Rahm, Alexander UL

E-print/Working paper (in press)

We give formulae for the Chen--Ruan orbifold cohomology for the orbifolds given by a Bianchi group acting on complex hyperbolic 3-space. The Bianchi groups are the arithmetic groups PSL_2(A), where A is ... [more ▼]

We give formulae for the Chen--Ruan orbifold cohomology for the orbifolds given by a Bianchi group acting on complex hyperbolic 3-space. The Bianchi groups are the arithmetic groups PSL_2(A), where A is the ring of integers in an imaginary quadratic number field. The underlying real orbifolds which help us in our study, given by the action of a Bianchi group on real hyperbolic 3-space (which is a model for its classifying space for proper actions), have applications in physics. We then prove that, for any such orbifold, its Chen-Ruan orbifold cohomology ring is isomorphic to the usual cohomology ring of any crepant resolution of its coarse moduli space. By vanishing of the quantum corrections, we show that this result fits in with Ruan's Cohomological Crepant Resolution Conjecture. [less ▲]

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See detailLe surpoids chez les élèves au Luxembourg
Heinz, Andreas UL

E-print/Working paper (2018)

Dans le cadre de l’enquête HBSC 2014, réalisée dans plusieurs pays de l’Union européenne, les élèves étaient interrogés concernant leur taille et leur poids pour permettre de calculer leur indice de masse ... [more ▼]

Dans le cadre de l’enquête HBSC 2014, réalisée dans plusieurs pays de l’Union européenne, les élèves étaient interrogés concernant leur taille et leur poids pour permettre de calculer leur indice de masse corporelle (IMC). Parmi les participants, 13 % sont trop maigres, 72 % ont un poids normal, 13 % sont en surpoids et 3 % sont obèses. En comparant avec les autres pays, il y a relativement peu d’enfants de 11 ans au Luxembourg en surpoids. La proportion des élèves de 15 ans en situation de surpoids se trouve au niveau de la moyenne internationale. Les enfants issus de familles de niveau socio-économique élevé ont un risque plus faible d’être en surpoids que ceux des familles avec un niveau plus bas. Les élèves de l’enseignement fondamental et du secondaire sont moins susceptibles d’être en surpoids que ceux du secondaire technique et du modulaire. [less ▲]

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See detailLa satisfaction de vie des élèves au Luxembourg
Heinz, Andreas UL

E-print/Working paper (2018)

Dans le cadre de l’enquête HBSC 2014, les élèves devaient indiquer à quel point ils étaient satisfaits de leur vie. La valeur « 0 » signifiait « la plus mauvaise vie possible » et la valeur « 10 » ... [more ▼]

Dans le cadre de l’enquête HBSC 2014, les élèves devaient indiquer à quel point ils étaient satisfaits de leur vie. La valeur « 0 » signifiait « la plus mauvaise vie possible » et la valeur « 10 » signifiait « la meilleur vie possible ». Parmi les participants du Luxembourg, 82 % ont indiqué une valeur de 6 ou plus, ce qui est défini comme étant « un niveau de satisfaction de vie élevé ». Pour 10 % d’entre eux, la satisfaction de vie était cotée avec la valeur moyenne de 5 et les 8 % restants ont indiqué une valeur inférieure à 5. La satisfaction de vie des filles moins âgées est plus élevée que celle des filles plus âgées. Chez les garçons, par contre, la satisfaction de vie reste pratiquement constante de 11 à 18 ans. Les garçons sont plus satisfaits de leur vie que les filles, ainsi que les enfants issus des familles avec un niveau socio-économique élevé, en comparaison avec ceux issus des familles ayant un niveau socio-économique faible. La satisfaction de vie est également liée aux problèmes de santé : les élèves qui indiquent souffrir fréquemment de douleurs, de tristesse, de mauvaise humeur / d’irritabilité, de nervosité, de problèmes à s’endormir ou de vertiges sont moins souvent satisfaits de leur vie. [less ▲]

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See detailLes problèmes de santé des élèves luxembourgeois
Heinz, Andreas UL

E-print/Working paper (2018)

Dans le cadre de l’enquête HBSC 2014, réalisée dans plusieurs pays de l’Union européenne, les élèves interrogés devaient indiquer la fréquence à laquelle ils souffraient des huit problèmes de santé ... [more ▼]

Dans le cadre de l’enquête HBSC 2014, réalisée dans plusieurs pays de l’Union européenne, les élèves interrogés devaient indiquer la fréquence à laquelle ils souffraient des huit problèmes de santé suivants : maux de tête ou de dos, douleurs abdominales, tristesse, irritabilité, nervosité, difficultés à s’endormir ou vertiges. Le résultat démontre que 41 % des élèves affirmaient avoir plusieurs fois par semaine voire quotidiennement au moins deux des huit problèmes précités. Les filles souffrent plus fréquemment de problèmes de santé que les garçons, ainsi que les élèves plus âgés comparativement aux plus jeunes. En outre, des enfants issus de familles avec un niveau socio-économique faible ont plus souvent des problèmes de santé que les enfants des familles ayant un niveau socio-économique élevé. Enfin, les élèves du secondaire technique et du modulaire souffrent plus fréquemment de problèmes de santé que les élèves de l’enseignement fondamental et du secondaire. [less ▲]

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See detailWWI: Kosakenmütze und roter Stern: Russische Gefangene in Luxemburg 1918
Ganschow, Inna UL

E-print/Working paper (2018)

Die vorliegende Teiluntersuchung beschäftigt sich mit den 3.100 russischen Kriegsgefangenen, die 1918 Luxemburg passierten. Etwa 300 blieben nachweislich in Luxemburg, da die sowjetische Ideologie in ... [more ▼]

Die vorliegende Teiluntersuchung beschäftigt sich mit den 3.100 russischen Kriegsgefangenen, die 1918 Luxemburg passierten. Etwa 300 blieben nachweislich in Luxemburg, da die sowjetische Ideologie in ihrer neuen Heimat, die nun Russische Sowjetische Föderative Sozialistische Republik hieß, sie nicht ansprach. In einer mikrohistorischen Perspektive werden mehrere Schicksale vorgeführt, anhand derer man zum einen die Bedingungen dieser Emigration versteht, die sich zwar auf neutralen Boden vollzog, jedoch unter der stetigen Verfolgung durch die deutsche Armee, die die Unabhängigkeit Luxemburgs wenig kümmerte. Zum anderen wird gezeigt, wie “Russisch” immer mehr mit “Kommunistisch” assoziiert wurde und alle Russen unter Verdacht standen, “rot” zu sein. [less ▲]

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See detailRussians in Luxembourg, WWII: Поиски старого друга
Ganschow, Inna UL

E-print/Working paper (2018)

Спустя семьдесят лет после окончания Второй мировой войны бывший люксембургский военнопленный решил найти своего старого русского друга, которого пригнали на принудительные работы в сталелитейной ... [more ▼]

Спустя семьдесят лет после окончания Второй мировой войны бывший люксембургский военнопленный решил найти своего старого русского друга, которого пригнали на принудительные работы в сталелитейной промышленности и сельском хозяйстве Люксембурга наравне с другими 4.000 узниками. Судьбы двух пленных переплелись, как они переплетутся между советскими и люксембургскими поданными в Европе еще не раз ... [less ▲]

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See detailRussians in Luxembourg: Русские в Вильтце - история первых эмигрантов
Ganschow, Inna UL

E-print/Working paper (2018)

Люксембургская русская община ведет свой отсчет с 1927 года – десятой годовщины Февральской, а потом и Октябрьской, революции. Девяносто лет назад прибыли эмигранты, прошедшие Гражданскую войну и ... [more ▼]

Люксембургская русская община ведет свой отсчет с 1927 года – десятой годовщины Февральской, а потом и Октябрьской, революции. Девяносто лет назад прибыли эмигранты, прошедшие Гражданскую войну и Крымскую эвакуацию 1920-го, положившую конец сопротивлению Белого движения на Юге России. Приехали в Люксембург, думая, что ненадолго, а остались... навсегда. [less ▲]

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See detailThe Global Triumph of the Research University: A Driving Force of Science Production
Baker, David P.; Dusdal, Jennifer UL; Powell, Justin J W UL et al

E-print/Working paper (2018)

The demand for higher education in countries around the world has never been higher. This increase in education levels has generated many benefits to society, including more knowledgeable citizens ... [more ▼]

The demand for higher education in countries around the world has never been higher. This increase in education levels has generated many benefits to society, including more knowledgeable citizens, advanced economies, and enhanced longevity. We have also seen countries and universities invest heavily in science, technology, engineering, and mathematics (STEM), including health (STEM+) research and scientific output. This has resulted in unexpected pure exponential growth in science production around the world. Increased competition, as well as boundary-spanning collaborations, drive unprecedented scientific advancement and technological innovation. In a book entitled The Century of Science: The Global Triumph of the Research University, we explore global scientific developments from the early 20th century to today. University-based research, especially, has risen globally to become the driving force of science production in STEM+ fields. Universities, with their multiple missions of research, teaching, and public service, are uniquely positioned to contribute to scientific output while simultaneously producing the next generation of scientists. [less ▲]

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See detailUniform gradient estimates on manifolds with a boundary and applications
Cheng, Li Juan UL; Thalmaier, Anton UL; Thompson, James UL

E-print/Working paper (2018)

We revisit the problem of obtaining uniform gradient estimates for Dirichlet and Neumann heat semigroups on Riemannian manifolds with boundary. As applications, we obtain isoperimetric inequalities, using ... [more ▼]

We revisit the problem of obtaining uniform gradient estimates for Dirichlet and Neumann heat semigroups on Riemannian manifolds with boundary. As applications, we obtain isoperimetric inequalities, using Ledoux's argument, and uniform quantitative gradient estimates, firstly for bounded C^2 functions with boundary conditions and then for the unit spectral projection operators of Dirichlet and Neumann Laplacians. [less ▲]

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See detailWhen Time Breaks: The Hiatus of Refugee Status
Van Der Walt, Johan Willem Gous UL

E-print/Working paper (2018)

“In the first place, we don’t like to be called ‘refugees.’ We ourselves call one another ‘newcomers’ or ‘immigrants.’” Already here, in the first sentence of Arendt’s essay “We Refugees,” does the hiatus ... [more ▼]

“In the first place, we don’t like to be called ‘refugees.’ We ourselves call one another ‘newcomers’ or ‘immigrants.’” Already here, in the first sentence of Arendt’s essay “We Refugees,” does the hiatus of refugee status become manifest. A divide already opens up between different habits of reference. Refugees refer to themselves in one way, non-refugees refer to them in another, and so does the projected or desired possibility of one world in which both refugees and non-refugees might find accommodation, split into two very different realities. Consciousness of the split is of course solely that of the refugees, at first. Initially, the hiatus is theirs only. Others – non-refugees – remain soundly oblivious to this fundamental split until such time as it brutally breaks into their world too, for instance, when the corpse of a four-year old child washes up on a beach, and washes up on every doorstep in a succession of media waves. And then the hiatus is suddenly everywhere and no one remains exempted. As the last sentence of Arendt’s essay contends forcefully, the split begins with the refugee status of some, but it ends with the bigger split of a world that begins to falter and fall apart: “The comity of European peoples went to pieces when, and because, it allowed its weakest member to be excluded and persecuted.” The comity of European peoples show all signs of going to pieces again today. When the comity of peoples goes to pieces, it is not only common space that cracks up, but also common time, the common time that warrants common space according to Kant’s Schematismuslehre. It is ultimately this breaking of time – the hiatus of time – that Arendt thematises elsewhere with reference to “the desolate aimless wanderings of Israeli tribes in the wilderness and the dangers which befell Aeneas before he reached the Italian shore.” “[T]his hiatus,” she continues, obviously creeps into all time speculations which deviate from the currently accepted notion of time as a continuous flow.” (Arendt On Revolution, 205). This text is also a supplementary discussion of my reviews of two recent monographs on Arendt. See: RECENT ARENDT SCHOLARSHIP: Review of The Wandering Thought of Hannah Arendt by Hans Jörg Sigwart, Palgrave MacMillan, 2016, ISBN: 978-1-137-48214-3, 147 pages (abbreviated as WT below), and Rightlessness in an Age of Rights. Hannah Arendt and the Contemporary Struggles of Migrants by Ayten Gündoğdu, New York: Oxford University Press: 2015, 298 pages, forthcoming in Constellations. [less ▲]

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See detailSuccessive convex approximation algorithms for sparse signal estimation with nonconvex regularizations
Yang, Yang UL; Pesavento, Marius; Chatzinotas, Symeon UL et al

E-print/Working paper (2018)

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See detailParallel and hybrid soft-thresholding algorithms with line search for sparse nonlinear regression
Yang, Yang UL; Pesavento, Marius; Chatzinotas, Symeon UL et al

E-print/Working paper (2018)

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See detailConnecting Personal Data of Third Country Nationals: Interoperability of EU Databases in the Light of the CJEU's Case Law on Data Retention
Quintel, Teresa Alegra UL

E-print/Working paper (2018)

On 12 December 2017, the EU Commission presented a proposal on the interoperability of EU large-scale Information Systems. The proposal seeks to enable all centralised EU databases for security, border ... [more ▼]

On 12 December 2017, the EU Commission presented a proposal on the interoperability of EU large-scale Information Systems. The proposal seeks to enable all centralised EU databases for security, border and migration management to be interconnected by 2020. The underlying IT systems retain data of Third Country Nationals (TCNs), namely travellers, applicants for international protection, information relating to visa applications or data on missing persons and criminals. With the proposal, the Commission seeks to create new possibilities to exchange information, manage migration challenges and to enhance the Union’s internal security. The interconnectivity of databases would introduce fundamental changes to the current structure of EU IT-systems and requires careful consideration and assessment of compliance with EU data protection standards. This also means that access to information in an interoperable system must be strictly aligned to the access rights of the underlying databases and that requesting authorities only obtain the data that they are authorized to access. With interoperability, data once held in silos would be retained in three new centralized databases and would be more easily accessible, also for the prevention, investigation and prosecution of crime. Where criminal investigations previously required multiple searches in separate databases, this cascading safeguard shall progressively be abandoned to streamline access to personal data by law enforcement authorities. Despite simplified access conditions, this would require new types of processing operations for which the interoperability proposal does not provide a legal basis. During recent years, several judgments of the Court of Justice of the European Union (CJEU) have highlighted the difficulty of striking a proper balance between the fundamental rights to privacy and data protection, enshrined in Article 7 and 8 of the Charter of Fundamental Rights of the European Union (EU Charter) with an increased demand for security and the surveillance of potential criminals. The Court repeatedly pointed out the need to strike a fair balance between these (allegedly) competing interests and emphasised that law enforcement authorities should not be granted access to personal data without prior authorization. Using the CJEU’s judgments as vehicle and considering the assumption that TCNs risk to become subject to data retention measures in a disproportionate manner, the following analysis seeks to assess both existing EU databases and their foreseen interoperability against the requirements established by the Court in order to evaluate their (in)-compatibility with the fundamental rights standards enshrined in the EU Charter. [less ▲]

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See detailDelaunay Triangulations of Points on Circles
despré, vincent; devillers, olivier; Parlier, Hugo UL et al

E-print/Working paper (2018)

Delaunay triangulations of a point set in the Euclidean plane are ubiquitous in a number of computational sciences, including computational geometry. Delaunay triangulations are not well defined as soon ... [more ▼]

Delaunay triangulations of a point set in the Euclidean plane are ubiquitous in a number of computational sciences, including computational geometry. Delaunay triangulations are not well defined as soon as 4 or more points are concyclic but since it is not a generic situation, this difficulty is usually handled by using a (symbolic or explicit) perturbation. As an alternative, we propose to define a canonical triangulation for a set of concyclic points by using a max-min angle characterization of Delaunay triangulations. This point of view leads to a well defined and unique triangulation as long as there are no symmetric quadruples of points. This unique triangulation can be computed in quasi-linear time by a very simple algorithm. [less ▲]

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See detailBayesian variable selection in linear dynamical systems
Aalto, Atte UL; Goncalves, Jorge UL

E-print/Working paper (2018)

We develop a method for reconstructing regulatory interconnection networks between variables evolving according to a linear dynamical system. The work is motivated by the problem of gene regulatory ... [more ▼]

We develop a method for reconstructing regulatory interconnection networks between variables evolving according to a linear dynamical system. The work is motivated by the problem of gene regulatory network inference, that is, finding causal effects between genes from gene expression time series data. In biological applications, the typical problem is that the sampling frequency is low, and consequentially the system identification problem is ill-posed. The low sampling frequency also makes it impossible to estimate derivatives directly from the data. We take a Bayesian approach to the problem, as it offers a natural way to incorporate prior information to deal with the ill-posedness, through the introduction of sparsity promoting prior for the underlying dynamics matrix. It also provides a framework for modelling both the process and measurement noises. We develop Markov Chain Monte Carlo samplers for the discrete-valued zero-structure of the dynamics matrix, and for the continuous-time trajectory of the system. [less ▲]

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See detailRisk and Refugee Migration
Joxhe, Majlinda UL; Bocqueho, Geraldine; Helstroffer, Jenny et al

E-print/Working paper (2018)

This paper uses the experimental setup of Tanaka et al. (2010) to measure refugees’ risk preferences. A sample of 206 asylum seekers was interviewed in 2017-18 in Luxembourg. Contrary to studies which ... [more ▼]

This paper uses the experimental setup of Tanaka et al. (2010) to measure refugees’ risk preferences. A sample of 206 asylum seekers was interviewed in 2017-18 in Luxembourg. Contrary to studies which focus on risk aversion in general, we analyze its components using a cumulative prospect theory (CPT) framework. We show that refugees exhibit particularly low levels of risk aversion compared to other populations and that CPT provides a better fit for modelling risk attitudes. Moreover, we include randomised temporary treatments provoking emotions and find a small significant impact on probability distortion. Robustness of the Tanaka et al. (2010) experimental framework is confirmed by including treatments regarding the embedding effect. Finally, we propose a theoretical model of refugee migration that integrates the insights from our experimental outcomes regarding the functional form of refugees’ decision under risk and the estimated parameter values. The model is then simulated using the data from our study. [less ▲]

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See detailLimit theorems for symmetric U-statistics using contractions
Döbler, Christian UL; Peccati, Giovanni UL

E-print/Working paper (2018)

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See detailExpediting in Two-Echelon Spare Parts Inventory Systems
Drent, Melvin UL; Arts, Joachim UL

E-print/Working paper (2018)

We consider a two-echelon spare parts inventory system consisting of one central warehouse and multiple local warehouses. Each warehouse keeps multiple types of repairable parts to maintain several types ... [more ▼]

We consider a two-echelon spare parts inventory system consisting of one central warehouse and multiple local warehouses. Each warehouse keeps multiple types of repairable parts to maintain several types of capital goods. The local warehouses face Poisson demand and are replenished by the central warehouse. We assume that unsatisfied demand is backordered at all warehouses. Furthermore, we assume deterministic lead times for the replenishments of the local warehouses. The repair shop at the central warehouse has two repair options for each repairable part: a regular repair option and an expedited repair option. Both repair options have stochastic lead times. Irrespective of the repair option, each repairable part uses a certain resource for its repair. Assuming a dual-index policy at the central warehouse and base stock control at the local warehouses, an exact and efficient evaluation procedure for a given control policy is formulated. To find an optimal control policy, we look at the minimization of total investment costs under constraints on both the aggregate mean number of backorders per capital good type and the aggregate mean fraction of repairs that are expedited per repair resource. For this non-linear non-convex integer programming problem, we develop a greedy heuristic and an algorithm based on decomposition and column generation. Both solution approaches perform very well with average optimality gaps of 1.56 and 0.23 percent, respectively, across a large test bed of industrial size. [less ▲]

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See detailThe Credit Structure Database
Leon, Florian UL

E-print/Working paper (2018)

We describe a new publicly available dataset on credit structure across the world over the period 1995-2014. The database contains two modules. The first part reports the structure of bank loan by types ... [more ▼]

We describe a new publicly available dataset on credit structure across the world over the period 1995-2014. The database contains two modules. The first part reports the structure of bank loan by types of borrowers (households vs. firms). Data are available for 143 countries. Household credit is breakdown between mortgage loans and other household loans (credit cards, car loans, student loans, etc.). Firm credit is decomposed into six sectors (agriculture, industry, construction, transport, trade and other services). The second module contains credit by maturity for 85 countries. Short-term credit is defined as loans with a maturity of one year or less and long-term credit as loans whose maturity exceeds one year. Database is freely available and downlable in Excel and Stata format at the following link: https://sites.google.com/site/florianleon/research/data [less ▲]

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See detailEnergy efficiency optimization in MIMO interference channels: A successive pseudoconvex approximation approach
Yang, Yang UL; Pesavento, Marius; Chatzinotas, Symeon UL et al

E-print/Working paper (2018)

Detailed reference viewed: 98 (23 UL)
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See detailBisymmetric and quasitrivial operations: characterizations and enumerations
Devillet, Jimmy UL

E-print/Working paper (2018)

We investigate the class of bisymmetric and quasitrivial binary operations on a given set X and provide various characterizations of this class as well as the subclass of bisymmetric, quasitrivial, and ... [more ▼]

We investigate the class of bisymmetric and quasitrivial binary operations on a given set X and provide various characterizations of this class as well as the subclass of bisymmetric, quasitrivial, and order-preserving binary operations. We also determine explicitly the sizes of these classes when the set X is finite. [less ▲]

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See detailAttacks and Countermeasures for White-box Designs
Biryukov, Alex UL; Udovenko, Aleksei UL

E-print/Working paper (2018)

In the traditional symmetric cryptography, the adversary has access only to the inputs and outputs of a cryptographic primitive. In the white-box model the adversary is given full access to the ... [more ▼]

In the traditional symmetric cryptography, the adversary has access only to the inputs and outputs of a cryptographic primitive. In the white-box model the adversary is given full access to the implementation. He can use both static and dynamic analysis as well as fault analysis in order to break the cryptosystem, e.g. to extract embedded secret key. Implementations secure in such model have many applications in industry. However, creating such implementations turns out to be a very challenging if not an impossible task. Recently, Bos et al. proposed a generic attack on white-box primitives called differential computation analysis (DCA). This attack applies to most existent white-box implementations both from academia and industry. The attack comes from side-channel cryptanalysis method. The most common method protecting against such side-channel attacks is masking. Therefore, masking can be used in white-box implementations to protect against the DCA attack. In this paper we investigate this possibility and present multiple generic attacks against masked white-box implementations. We use the term “masking” in a very broad sense. As a result, we deduce new constraints that any secure white-box implementation must satisfy. We suggest partial countermeasures against the attacks. Some of our attacks were successfully applied to the WhibOx 2017 challenges. [less ▲]

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See detailGradient Estimates on Dirichlet and Neumann Eigenfunctions
Arnaudon, Marc; Thalmaier, Anton UL; Wang, Feng-Yu

E-print/Working paper (2018)

By methods of stochastic analysis on Riemannian manifolds, we derive explicit two-sided gradient estimates for Dirichlet eigenfunctions on a d-dimensional compact Riemannian manifold D with boundary ... [more ▼]

By methods of stochastic analysis on Riemannian manifolds, we derive explicit two-sided gradient estimates for Dirichlet eigenfunctions on a d-dimensional compact Riemannian manifold D with boundary. Corresponding two-sided gradient estimates for Neumann eigenfunctions are derived in the second part of the paper. [less ▲]

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See detailBrexit Seen from Luxembourg
Högenauer, Anna-Lena UL

E-print/Working paper (2018)

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See detailAlonso and the scaling of urban profiles
Delloye, Justin; Lemoy, Rémi UL; Caruso, Geoffrey UL

E-print/Working paper (2018)

Urban characteristics scaling with total population has become an important urban research field since one needs to better understand the benefits and disadvantages of urban growth and fur- ther ... [more ▼]

Urban characteristics scaling with total population has become an important urban research field since one needs to better understand the benefits and disadvantages of urban growth and fur- ther population concentration. Urban scaling research, however, is largely disconnected from the empirics and theory of intra-urban structure for it considers averaged attributes and ignores resi- dential choice trade-offs between transport and housing costs within cities. Using this fundamental trade-off, the monocentric model of Alonso provides theory to urban density profiles. However, it is silent about how these profiles scale with population, thus preventing empirical scaling studies to anchor in a strong micro-economic theory. This paper fixes this gap by introducing power laws for land and for population density in the Alonso model. From an augmented model with land use, we derive the conditions at which equilibrium profiles match recent empirical findings about the scaling of urban land and population density profiles in European cities. We find that the Alonso model is theoretically compatible with the observed scaling of population density profiles and leads to a satisfactory representation of European cities. The conditions for this compatibility refine current understanding of wage and transport costs elasticities with population. Although they require a scaling power of the profile of the share of urbanised land that is different from what is observed, it is argued that alternatives specifications of transport cost functions could solve this issue. Thus our results call for revisiting theories about land development and housing processes as well as the empirics of agglomeration benefits and transport costs. [less ▲]

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See detailLong-term finance and entrepreneurship
Leon, Florian UL

E-print/Working paper (2018)

This paper investigates whether long-term finance affects the firm entry across the world. We construct a new database on short-term and long-term credit provided by commercial banks to the private sector ... [more ▼]

This paper investigates whether long-term finance affects the firm entry across the world. We construct a new database on short-term and long-term credit provided by commercial banks to the private sector in 85 countries over the period 1995-2014. We then analyze whether differences in entrepreneurship are correlated with the provision of short-term and long-term bank credit. Data on entrepreneurship are extracted from two frequently used databases: the Global Entrepreneurship Monitoring dataset and Entrepreneurship Database, each of which captures different aspects of firm creation. Econometric results indicate that long-term credit does not stimulate the firm entry. On the contrary, we find that short-term credit exerts a positive impact at each stage of firm creation from activity birth to registration. Our findings are robust to a battery of sensitivity tests, including additional control variables, alternative dependent variables, alternative sample, and changes in econometric specification. Our findings suggest that better provision of short-term credit allows entrepreneurs to apply for a formal loan instead of relying exclusively on informal loans or internal funds, contrary to long-term loans [less ▲]

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See detailFragebogen HBSC 2018 (enseignement fondamental)
Heinz, Andreas UL

E-print/Working paper (2018)

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See detailDo banks and microfinance institutions compete? Microevidence from Madagascar
Leon, Florian UL; Baraton, Pierrick

E-print/Working paper (2018)

In recent years, both microfinance institutions (MFIs) and banks across the world have been converging towards the financing of small enterprises with high financing needs. This paper scrutinizes whether ... [more ▼]

In recent years, both microfinance institutions (MFIs) and banks across the world have been converging towards the financing of small enterprises with high financing needs. This paper scrutinizes whether banks and MFIs compete each other as a result of recent transformations in both industries. In doing so, we study whether the loan strategy of a microfinance institution is shaped by the local presence of a bank. Specifically, we investigate whether bank proximity influences loan conditions provided by one of the largest microfinance institutions in Madagascar. We employ an original panel dataset of 32,374 loans granted to 14,834 borrowers over the period 2008-2014. We find that the closer a bank is located to a given MFI borrower, the larger the loan obtained and the less collateral required. These results are insensitive to several robustness tests for possible endogeneity of distance, sample selection issue, and alternative specifications. In addition, findings are stronger for larger and more established (older) firms in line with our hypothesis. [less ▲]

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See detailDemographics and FDI: Lessons from China's One-Child Policy
Donaldson, John B.; Koulovatianos, Christos UL; Li, Jian et al

E-print/Working paper (2018)

Lucas (1990) argues that the neoclassical adjustment process fails to explain the relative paucity of FDI inflows from rich to poor countries. In this paper we consider a natural experiment: using China ... [more ▼]

Lucas (1990) argues that the neoclassical adjustment process fails to explain the relative paucity of FDI inflows from rich to poor countries. In this paper we consider a natural experiment: using China as the treated country and India as the control, we show that the dynamics of the relative FDI flows subsequent to the implementation of China's one-child policy, as seen in the data, are consistent with neoclassical fundamentals. In particular, following the introduction of the one-child policy in China, the capital-labor (K/L) ratio of China increased relative to that of India, and, simultaneously, relative FDI inflows into China vs. India declined. These observations are explained in the context of a simple neoclassical OLG paradigm. The adjustment mechanism works as follows: the reduction in the (urban) labor force due to the one-child policy increases the savings per capita. This increases the K/L ratio and reduces the marginal product of capital (MPK). The reduction in MPK (relative to India) reduces the relative attractiveness of investment in China and is thus associated with lower FDI/GDP ratios. Our paper contributes to the nascent literature exploring demographic transitions and their effects on FDI flows. [less ▲]

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See detailFragebogen HBSC 2018 (enseignement secondaire)
Heinz, Andreas UL

E-print/Working paper (2018)

Detailed reference viewed: 26 (2 UL)
See detailLa réponse au défi migratoire : «Europe souveraine» ou «souverainisme de repli» ?
Gatti, Mauro UL

E-print/Working paper (2018)

La migration est probablement le « défi majeur » de l’Europe, aujourd’hui et dans les années qui viennent, comme le reconnaît Emmanuel Macron dans son discours de la Sorbonne de septembre 2017. On peut ... [more ▼]

La migration est probablement le « défi majeur » de l’Europe, aujourd’hui et dans les années qui viennent, comme le reconnaît Emmanuel Macron dans son discours de la Sorbonne de septembre 2017. On peut noter, par ailleurs, que la gestion de ce défi est à présent inadéquate : si 285.000 migrants ont été sauvés par des opérations coordonnées par l’Union européenne, 3.139 sont morts en 2017 ; en outre, l’état des droits des migrants dans l’Union et, surtout, dans les pays partenaires, reste problématique. Le « souverainisme de repli » n’assure aucune solution : « l’Europe seule peut, en un mot, assurer une souveraineté réelle » (Macron). Et la souveraineté de l’Europe – conçue comme la « capacité à exister dans le monde actuel pour y défendre nos valeurs et nos intérêts » – ne peut que s’assurer par la « solidarité » entre les Etats membres. Emmanuel Macron propose deux solutions au défi de la migration, qui paraissent toutefois insuffisantes ou illusoires : la création d’un « espace commun des frontières » vis-à- vis de l’extérieur et une gestion plus efficace de l’asile à l’intérieur de l’Union. [less ▲]

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See detailFEniCS-Shells: an open-source library for simulating thin structures
Hale, Jack UL; Brunetti, Matteo; Bordas, Stéphane UL et al

E-print/Working paper (2018)

Simulating thin structures implies solving non-linear partial differential equations defined on manifolds, which can include higher-order derivatives and/or stiff terms. Implementing effective locking ... [more ▼]

Simulating thin structures implies solving non-linear partial differential equations defined on manifolds, which can include higher-order derivatives and/or stiff terms. Implementing effective locking-free discretisation techniques for nonlinear plates and shells is a challenging and highly technical task. We present FEniCS-Shells, an open-source library for simulating thin structures using the finite element method, based on the FEniCS Project. Leveraging the high-level symbolic capabilities of the Unified Form Language (UFL) and the automatic code generation facilities of the FENICS Form Compiler (FFC), FEniCS-Shells allows for the concise formulation of discretisations of various thin-structural theories, including linear and nonlinear geometrically exact Naghdi shell models, the Marguerre-von Kármán shallow shell model, and the Reissner-Mindlin plate model. Mixed Interpolation of Tensorial Component (MITC) and Partial Selective Reduced Integration (PSRI) numerical methods are used to alleviate shear- and membrane-locking issues. The effectiveness of these approaches and the ease of writing solvers for non-linear shell models is illustrated through a large set of verification tests and demo codes. FEniCS-Shells can run without modification on high-performance computing (HPC) architectures. [less ▲]

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See detailBig Moves of Mutual Funds
Lehnert, Thorsten UL

E-print/Working paper (2018)

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See detailMath around the Clock
Perucca, Antonella UL

E-print/Working paper (2018)

We present several original arithmetical clocks presenting the numbers from 1 to 12 according to some specific theme (e.g. use only the digit 7).

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See detailWHY IS THE MARKET SKEWNESS-RETURN RELATIONSHIP NEGATIVE?
Lehnert, Thorsten UL

E-print/Working paper (2018)

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

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

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See detailGovernance and Price Jumps
Lehnert, Thorsten UL

E-print/Working paper (2018)

Some of the world’s poorest countries have demonstrated that political leadership and practical policies make a difference. Good governance could help to strengthen accountability, enhance participation ... [more ▼]

Some of the world’s poorest countries have demonstrated that political leadership and practical policies make a difference. Good governance could help to strengthen accountability, enhance participation and break down inequalities. Furthermore, a country’s quality of government has a positive effect on the development of its financial market and equity returns. In particular, it lowers equity volatility and, therefore, the costs of equity financing, which further helps to reduce inequalities. While price jumps are prevalent in stock markets all over the world, previous literature provides little guidance about the international nature of jumps and its relationship with country characteristics. Jumps are found to be far less systematic than the smooth (non-jump) component of country price indexes. Hence, if jumps are more idiosyncratic, governance should primarily affect the jump risk component of stock market volatility. This is good news for international investors, because diversification provides insurance against jumps. Relying on an equilibrium asset-pricing model in an economy under jump diffusion, I decompose the moments of the returns of international stock markets into a diffusive (systematic) risk and a (idiosyncratic) jump risk part. Using stock market data for a balanced panel of 52 countries, my results suggest that governance is an important determinant of (idiosyncratic) jump risk. Stock markets in poorly governed countries are characterized by higher volatility and more negative return asymmetry, primarily driven by the higher jump risk. Among the different governance indicators analyzed, the regulatory quality, the government effectiveness and the control of corruption appear to be most important. Results are robust to the inclusion of various controls for other country- or market-specific characteristics. My results have important policy implications. [less ▲]

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See detailMutant Quality Indicators
Papadakis, Mike UL; Titcheu Chekam, Thierry UL; Le Traon, Yves UL

E-print/Working paper (2018)

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See detailAccounting for Differences in Income Inequality across Countries: Ireland and the United Kingdom
Sologon, Denisa M.; van Kerm, Philippe UL; Li, Jinjing et al

E-print/Working paper (2018)

This paper proposes a framework for studying international differences in the distribution of household income. Integrating micro-econometric and micro-simulation approaches in a decomposition analysis it ... [more ▼]

This paper proposes a framework for studying international differences in the distribution of household income. Integrating micro-econometric and micro-simulation approaches in a decomposition analysis it quantifies the role of tax-benefit systems, employment and occupational structures, labour prices and market returns, and demographic composition in accounting for differences in income inequality across countries. Building upon EUROMOD (the European tax-benefit calculator) and its harmonized datasets, the model is portable and can be implemented for any cross-country comparisons within the EU. An application to the UK and Ireland--two countries that have much in common while displaying different levels of inequality--shows that differences in tax-benefit rules between the two countries account for roughly half of the observed difference in disposable household income inequality. Demographic differences play negligible roles. The Irish tax-benefit system is more redistributive than UK's due to a higher tax progressivity and higher average transfer rates. These are largely attributable to policy parameter differences, but also to differences in pre-tax, pre-transfer income distributions. [less ▲]

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See detailIsolation of nucleic acids from low biomass samples: detection and removal of sRNA contaminants
Heintz-Buschart, Anna; Yusuf, Dilmurat; Kaysen, Anne UL et al

E-print/Working paper (2017)

Sequencing-based analyses of low-biomass samples are known to be prone to misinterpretation due to the potential presence of contaminating molecules derived from laboratory reagents and environments. Due ... [more ▼]

Sequencing-based analyses of low-biomass samples are known to be prone to misinterpretation due to the potential presence of contaminating molecules derived from laboratory reagents and environments. Due to its inherent instability, contamination with RNA is usually considered to be unlikely. Here we report the presence of small RNA (sRNA) contaminants in widely used microRNA extraction kits and means for their depletion. Sequencing of sRNAs extracted from human plasma samples was performed and significant levels of non-human (exogenous) sequences were detected. The source of the most abundant of these sequences could be traced to the microRNA extraction columns by qPCR-based analysis of laboratory reagents. The presence of artefactual sequences originating from the confirmed contaminants were furthermore replicated in a range of published datasets. To avoid artefacts in future experiments, several protocols for the removal of the contaminants were elaborated, minimal amounts of starting material for artefact-free analyses were defined, and the reduction of contaminant levels for identification of bona fide sequences using 'ultra-clean' extraction kits was confirmed. In conclusion, this is the first report of the presence of RNA molecules as contaminants in laboratory reagents. The described protocols should be applied in the future to avoid confounding sRNA studies. [less ▲]

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See detailFundamental limits to helical edge conductivity due to sphin-phonon scattering
Groenendijk, Solofo UL; Dolcetto; Schmidt, Thomas UL

E-print/Working paper (2017)

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See detailUniversal scaling of quench-induced correlations in a one-dimensional channel at finite temperature
Calzona, Alessio UL; Gambetta, Filippo Maria; Carrega, Matteo et al

E-print/Working paper (2017)

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See detailDie allgemeine Lebenszufriedenheit von Schülern in Luxemburg
Kern, Matthias Robert UL; Residori, Caroline UL; Heinz, Andreas UL et al

E-print/Working paper (2017)

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See detailGesundheitsbeschwerden von Schülern in Luxemburg
Heinz, Andreas UL; Kern, Matthias Robert UL; Residori, Caroline UL et al

E-print/Working paper (2017)

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See detailInternetdelikte und die Herausforderungen des Forum Shoppings
Schmitz, Sandra UL

E-print/Working paper (2017)

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See detailÜbergewicht bei Schülern in Luxemburg
Residori, Caroline UL; Kern, Matthias Robert UL; Heinz, Andreas UL et al

E-print/Working paper (2017)

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See detailL'ethnographie du travail
de Saint-Georges, Ingrid UL

E-print/Working paper (2017)

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See detailMechanizing Principia Logico-Metaphysica in Functional Type Theory
Kirchner, Daniel; Benzmüller, Christoph UL; Zalta, Edward N.

E-print/Working paper (2017)

Principia Logico-Metaphysica proposes a foundational logical theory for metaphysics, mathematics, and the sciences. It contains a canonical development of Abstract Object Theory [AOT], a metaphysical ... [more ▼]

Principia Logico-Metaphysica proposes a foundational logical theory for metaphysics, mathematics, and the sciences. It contains a canonical development of Abstract Object Theory [AOT], a metaphysical theory (inspired by ideas of Ernst Mally, formalized by Zalta) that differentiates between ordinary and abstract objects. This article reports on recent work in which AOT has been successfully represented and partly automated in the proof assistant system Isabelle/HOL. [less ▲]

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See detailTime Averages of Markov Processes and Applications to Two-Timescale Problems
Pepin, Bob UL

E-print/Working paper (2017)

Detailed reference viewed: 17 (0 UL)
See detail3D Printing: The Next 5 years by Claude Wolf – Into the Future engineered by the Zs
Wolf, Claude UL

E-print/Working paper (2017)

3D Printing: The Next 5 years by Claude Wolf – Into the Future engineered by the Zs The future of 3D Printing or Additive Manufacturing [AM] will be driven by the next generation of engineers who are just ... [more ▼]

3D Printing: The Next 5 years by Claude Wolf – Into the Future engineered by the Zs The future of 3D Printing or Additive Manufacturing [AM] will be driven by the next generation of engineers who are just about to qualify, the Z generation (1994-2010). Do we, educators, know this Z generation? Do we know what motivates them? The Z generation is a generation of digital natives interacting with PCs, iPads, smartphones and the internet since birth, a pragmatic and short term orientated generation. Our prejudice brands them as unprepared and unmotivated, with their 10 second attention spans, but in reality, they have already proven they are creative, determined and hardworking as well as team oriented, when they are given the opportunity. They have understood that 3D printing offers them this opportunity. [less ▲]

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See detailScattering theory without injectivity radius assumptions and spectral stability for the Ricci flow
Güneysu, Batu; Thalmaier, Anton UL

E-print/Working paper (2017)

We prove a completely new integral criterion for the existence and completeness of the wave operators W_{\pm}(-\Delta_h,-\Delta_g, I_{g,h}) corresponding to the (unique self-adjoint realizations of) the ... [more ▼]

We prove a completely new integral criterion for the existence and completeness of the wave operators W_{\pm}(-\Delta_h,-\Delta_g, I_{g,h}) corresponding to the (unique self-adjoint realizations of) the Laplace-Beltrami operators -\Delta_j, j=g,h, that are induced by two quasi-isometric complete Riemannian metrics g and h on an open manifold M. In particular, this result provides a criterion for the absolutely continuous spectra of -\Delta_g and -\Delta_h to coincide. Our proof relies on estimates that are obtained using a probabilistic Bismut type formula for the gradient of a heat semigroup. Unlike all previous results, our integral criterion only requires some lower control on the Ricci curvatures and some upper control on the heat kernels, but no control at all on the injectivity radii. As a consequence, we obtain a stability result for the absolutely continuous spectrum under a Ricci flow. [less ▲]

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See detailTommaso Padoa-Schioppa [biography]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

Tommaso Padoa-Schioppa (1940-2010) was an Italian banker, economist, and politician. He was one of the "architects of the euro" and helped to push forward the financial, monetary, and economic integration ... [more ▼]

Tommaso Padoa-Schioppa (1940-2010) was an Italian banker, economist, and politician. He was one of the "architects of the euro" and helped to push forward the financial, monetary, and economic integration of Europe. [less ▲]

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See detailDynamics of Income Rank Volatility: Evidence from Germany and the US
Chauvel, Louis UL; Hartung, Anne UL; Palmisano, Flaviana

E-print/Working paper (2017)

This paper presents a methodology for comparing income rank volatility profiles over time and across distributions. While most of the existing measures are affected by changes in marginal distributions ... [more ▼]

This paper presents a methodology for comparing income rank volatility profiles over time and across distributions. While most of the existing measures are affected by changes in marginal distributions, this paper proposes a framework that is based on individuals’ relative positions in the distribution, and is neutral in relation to structural changes that occur in the economy. Applying this approach to investigate rank volatility in Germany and the US over three decades, we show that while poorer individuals within both countries are the most volatile, the volatility trend for the middle class in each of these countries differs. [less ▲]

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See detailWeakly Inscribed Polyhedra
chen, hao; Schlenker, Jean-Marc UL

E-print/Working paper (2017)

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See detailTowards a Quantitative Averaging Principle for Stochastic Differential Equations
Pepin, Bob UL

E-print/Working paper (2017)

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Peer Reviewed
See detailIsogeometric analysis of thin Reissner-Mindlin plates and shells: Locking phenomena and generalized local B-bar method
Hu, Qingyuan UL; Xia, Yang; Natarajan, Sundararajan et al

E-print/Working paper (2017)

We propose a generalized local $\bar{B}$ framework, addressing locking in degenerated Reissner-Mindlin plate and shell formulations in the context of isogeometric analysis. Parasitic strain components are ... [more ▼]

We propose a generalized local $\bar{B}$ framework, addressing locking in degenerated Reissner-Mindlin plate and shell formulations in the context of isogeometric analysis. Parasitic strain components are projected onto the physical space locally, i.e. at the element level, using a least-squares approach. The formulation is general and allows the flexible utilization of basis functions of different order as the projection bases. The present formulation is much cheaper computationally than the global $\bar{B}$ method. Through numerical examples, we show the consistency of the scheme, although the method is not Hu-Washizu variationally consistent. The numerical examples show that the proposed formulation alleviates locking and yields good accuracy for various thicknesses, even for slenderness ratios of $1 \times 10^5$, and has the ability to capture deformations of thin shells using relatively coarse meshes. From the detailed numerical study, it can be opined that the proposed method is less sensitive to locking and mesh distortion. [less ▲]

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See detailDemocratic legitimacy [glossary]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

A political institution is legitimate when it succeeds in persuading people of the normative necessity of its existence. In a democratic system, this can be based both on various forms of popular consent ... [more ▼]

A political institution is legitimate when it succeeds in persuading people of the normative necessity of its existence. In a democratic system, this can be based both on various forms of popular consent (democratic legitimacy) and on other kinds of foundations (generic legitimacy). With reference to the European Union, debates have focused on empirical support for the EU, the nature of its "democratic deficit", and the potential conflict between European integration and national democratic sovereignty. [less ▲]

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See detailOn functional equations characterizing derivations: methods and examples
Gselmann, Eszter; Kiss, Gergely UL; Vincze, Csaba

E-print/Working paper (2017)

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See detailReductions of points on algebraic groups
Lombardo, Davide; Perucca, Antonella UL

E-print/Working paper (2017)

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See detailNotes on the Schwarzian tensor and measured foliations at infinity of quasifuchsian manifolds.
Schlenker, Jean-Marc UL

E-print/Working paper (2017)

The boundary at infinity of a quasifuchsian hyperbolic manifold is equiped with a holomorphic quadratic differential. Its horizontal measured foliation $f$ can be interpreted as the natural analog of the ... [more ▼]

The boundary at infinity of a quasifuchsian hyperbolic manifold is equiped with a holomorphic quadratic differential. Its horizontal measured foliation $f$ can be interpreted as the natural analog of the measured bending lamination on the boundary of the convex core. This analogy leads to a number of questions. We provide a variation formula for the renormalized volume in terms of the extremal length $\ext(f)$ of $f$, and an upper bound on $\ext(f)$. \par We then describe two extensions of the holomorphic quadratic differential at infinity, both valid in higher dimensions. One is in terms of Poincar\'e-Einstein metrics, the other (specifically for conformally flat structures) of the second fundamental form of a hypersurface in a "constant curvature" space with a degenerate metric, interpreted as the space of horospheres in hyperbolic space. This clarifies a relation between linear Weingarten surfaces in hyperbolic manifolds and Monge-Amp\`ere equations. Notes aiming at clarifying the relations between different points of view and introducing one new notion, no real result. Not intended to be submitted at this point [less ▲]

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See detailArbeitsmotivation von Arbeitnehmern in Luxemburg
Sischka, Philipp UL; Steffgen, Georges UL

E-print/Working paper (2017)

Die europäische Studie EWCS (Eurofund, 2016a, 2016b) zeigt auf, dass sich die Arbeitsmotivation der Arbeitnehmer in Luxemburg eher im mittleren Bereich wiederfindet. Die nationale Studie Quality of Work ... [more ▼]

Die europäische Studie EWCS (Eurofund, 2016a, 2016b) zeigt auf, dass sich die Arbeitsmotivation der Arbeitnehmer in Luxemburg eher im mittleren Bereich wiederfindet. Die nationale Studie Quality of Work Index belegt nur geringfügige Unterschiede der Arbeitsmotivation sowohl zwischen männlichen und weiblichen Arbeitnehmern als auch zwischen den verschiedenen Altersgruppen. Arbeitnehmer in einer Vorgesetztenposition, Manager und Führungskräfte zeigen im Durchschnitt eine höhere, Hilfsarbeitskräfte dagegen im Durchschnitt eine geringere Arbeitsmotivation. Überdurchschnittlich motiviert erweisen sich Arbeitnehmer in Nichtregierungsorganisationen (NGO). Die Arbeitsmotivation ist dabei mit verschiedenen psychosozialen Abeitsbedingungen sowie Arbeitsrahmenbedingungen korreliert. Parizipation an Entscheidungen, Feedback von Kollegen und Vorgesetzten, Kooperation unter Kollegen sowie Rollenklarheit sind positiv mit Arbeitsmotivation assoziert, das Erleben von Konkurrenz und Mobbing sind hingegen negativ assoziiert. Hinsichtlich Arbeitsrahmenbedingungen weist vor allem Arbeitsplatzsicherheit einen hohen Zusammenhang mit der Arbeitsmotivation auf, gefolgt von Einkommenszufriedenheit und Ausbildungsmöglichkeiten. [less ▲]

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See detailAssociative idempotent nondecreasing functions are reducible
Kiss, Gergely UL; Somlai, Gabor

E-print/Working paper (2017)

An n-variable associative function is called reducible if it can be written as a composition of a binary associative function. In this paper we summarize the known results when the function is defined on ... [more ▼]

An n-variable associative function is called reducible if it can be written as a composition of a binary associative function. In this paper we summarize the known results when the function is defined on a chain and nondecreasing. The main result of this paper shows that associative idempotent and nondecreasing functions are uniquely reducible. [less ▲]

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See detailHerman Van Rompuy [biography]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

Herman Van Rompuy (b. 1947) is a Belgian and European politician. In his capacity as President of the European Council (2009-2014), he played a key role in the EU's response to the financial crisis and in ... [more ▼]

Herman Van Rompuy (b. 1947) is a Belgian and European politician. In his capacity as President of the European Council (2009-2014), he played a key role in the EU's response to the financial crisis and in the strengthening of the European framework of economic governance. [less ▲]

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See detailWolfgang Schäuble [biography]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

Wolfgang Schäuble (b. 1942) is an active German politician. He played a key role in the German reunification process (1989-90) and in the management of the Eurozone crisis (since 2009).

Detailed reference viewed: 7 (0 UL)
See detailSolidarity [glossary]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

The principle of solidarity plays a key role in discussions of social, economic, and political issues. A polysemic notion, it may interrogate either individuals or public authorities. It often represents ... [more ▼]

The principle of solidarity plays a key role in discussions of social, economic, and political issues. A polysemic notion, it may interrogate either individuals or public authorities. It often represents the counterpart of competition in the analysis and assessment of social norms and public policies. [less ▲]

Detailed reference viewed: 7 (0 UL)
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See detailWho Trade at Better Prices?
Wolff, Christian UL; Ekkayokkaya, Manapol

E-print/Working paper (2017)

Detailed reference viewed: 13 (0 UL)
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See detailLocalisation résidentielle de la population étrangère selon la nationalité et la structure urbaine au Luxembourg
Pigeron-Piroth, Isabelle UL; Heinz, Andreas UL; Caruso, Geoffrey UL

E-print/Working paper (2017)

The number of foreigners living in Luxembourg is still rising and represents today about 48% of the inhabitants. This study focuses on the description and mapping of the place of residence for the ... [more ▼]

The number of foreigners living in Luxembourg is still rising and represents today about 48% of the inhabitants. This study focuses on the description and mapping of the place of residence for the different nationalities living in Luxembourg. It seeks to underline differences through indicators built from the 2011 census data. We focus on the territorial distribution of the different nationalities by taking into account the urban structure and distance to jobs. If differences according to nationalities in the residential behavior of households can be empirically identified they may raise issues of spatial equity and (un)equal accessibility to job market. We analyse whether the geographic location of different nationalities in Luxembourg is linked to urbanisation level, the distance to the “poles d´emploi” or general accessibility to jobs. [less ▲]

Detailed reference viewed: 56 (4 UL)
See detailThe European Commission’s "Reflection Paper on Harnessing Globalisation"
Chiocchetti, Paolo UL

E-print/Working paper (2017)

The new EC reflection paper on globalisation sets new accents, but contains no major departure from current policy orientations. It takes a clear stand for free trade, while attacking "unfair competition ... [more ▼]

The new EC reflection paper on globalisation sets new accents, but contains no major departure from current policy orientations. It takes a clear stand for free trade, while attacking "unfair competition" and arguing for a "balanced, rules-based and progressive trade and investment agenda". Despite its insistence on a managed globalisation and a fair redistribution of its benefits, its proposals are unlikely to allay domestic anxieties and external criticism. [less ▲]

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Peer Reviewed
See detailCross-border mergers and acquisitions: Evidence from Indochina
Wolff, Christian UL

E-print/Working paper (2017)

Detailed reference viewed: 16 (1 UL)
Full Text
See detailState of the Art in Lightweight Symmetric Cryptography
Biryukov, Alex UL; Perrin, Léo Paul UL

E-print/Working paper (2017)

Lightweight cryptography has been one of the ``hot topics'' in symmetric cryptography in the recent years. A huge number of lightweight algorithms have been published, standardized and/or used in ... [more ▼]

Lightweight cryptography has been one of the ``hot topics'' in symmetric cryptography in the recent years. A huge number of lightweight algorithms have been published, standardized and/or used in commercial products. In this paper, we discuss the different implementation constraints that a ``lightweight'' algorithm is usually designed to satisfy. We also present an extensive survey of all lightweight symmetric primitives we are aware of. It covers designs from the academic community, from government agencies and proprietary algorithms which were reverse-engineered or leaked. Relevant national (\nist{}...) and international (\textsc{iso/iec}...) standards are listed. We then discuss some trends we identified in the design of lightweight algorithms, namely the designers' preference for \arx{}-based and bitsliced-S-Box-based designs and simple key schedules. Finally, we argue that lightweight cryptography is too large a field and that it should be split into two related but distinct areas: \emph{ultra-lightweight} and \emph{IoT} cryptography. The former deals only with the smallest of devices for which a lower security level may be justified by the very harsh design constraints. The latter corresponds to low-power embedded processors for which the \aes{} and modern hash function are costly but which have to provide a high level security due to their greater connectivity. [less ▲]

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See detailLa restructuration des dettes publiques saisie par le droit de l'Union européenne
Allemand, Frederic UL

E-print/Working paper (2017)

En juillet 2015, le sommet de la zone euro fait part de l'existence de "sérieux doutes" sur le caractère soutenable de la dette grecque. La possibilité d'un reprofilage de la dette est envisagé et sa ... [more ▼]

En juillet 2015, le sommet de la zone euro fait part de l'existence de "sérieux doutes" sur le caractère soutenable de la dette grecque. La possibilité d'un reprofilage de la dette est envisagé et sa discussion reportée à la réalisation de la première évaluation des mesures d'ajustement mises en oeuvre par la Grèce. Toute décote nominale est cependant formellement exclue, car contraire au droit de l'Union. Les discussions se sont ouvertes au printemps 2016 sur les modalités d'allègement de la dette publique de la Grèce. Le sujet a été au coeur de la réunion de l'Eurogroupe du 22 mai. Aucun accord n'a été trouvé, mais les discussions continuent. Dans ce contexte, Frédéric Allemand a présenté le 17 mai dernier une communication sur la saisine des opérations de restructuration par le droit de l'Union lors du séminaire de recherche pluridisciplinaire "Les administrations publiques à l'épreuve de leur dette" organisé par Jean-François Boudet (Université Paris II) et Caroline Lequesne-Roth (Université de Nice). L'auteur conclut à la compétence de l'Union pour encadrer la restructuration des dettes publiques des États membres. [less ▲]

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See detailUnderstanding audit oversight transformation : ramifications of institutional work and the power of (de-)mythologizing
Löhlein, Lukas; Muessig, Anke UL

E-print/Working paper (2017)

This study investigates the dynamics that transformed audit oversight in Germany from an instrument, organized by the profession, to maintain international legitimacy into a regulatory regime that is ... [more ▼]

This study investigates the dynamics that transformed audit oversight in Germany from an instrument, organized by the profession, to maintain international legitimacy into a regulatory regime that is integrated into the state apparatus. While prior research has focused on countries where the global demand for oversight structures overlapped with local pressures for regulatory reforms, we examine the diffusion of patterns of control within a context that is characterized by a strong mythologized belief in the German qualified statutory auditor and professional self-regulation. By analysing archival documents and interviews with key actors, we investigate through the lens of institutional work how initially the audit establishment maintained the existing self-regulatory logic despite, and because of, the implementation of formal independent oversight structures. We illustrate how the institutional work of small auditors aimed at disrupting the large audit firms’ field dominance unintentionally undermined the mythologized self-regulation. In doing so, we offer insights into how institutional myth is both constructed and dismantled. Our focus on multiple actors allows us to shed light on how parallel institutional work of distinct actors can lead to mutually effective and unintended institutional consequences. We argue that a successful institutional worker executes a combination of two basic types of work, which we refer to as existential and instrumental modes of work. Finally, comparing our findings with literature on audit oversight in other countries allows us to conceptualize audit oversight along a political-operational dimension and a public-private dimension. [less ▲]

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See detailGesundheitsverhalten von Arbeitnehmern in Luxemburg
Sischka, Philipp UL; Steffgen, Georges UL

E-print/Working paper (2017)

Insbesonders unter den jüngeren Arbeitnehmern und unter den Arbeitnehmern mit geringer Bildung ist der Anteil der Raucher vergleichsweise hoch. Männliche und ältere Arbeitnehmer weisen wieder einen ... [more ▼]

Insbesonders unter den jüngeren Arbeitnehmern und unter den Arbeitnehmern mit geringer Bildung ist der Anteil der Raucher vergleichsweise hoch. Männliche und ältere Arbeitnehmer weisen wieder einen vergleichsweise hohen Alkoholkonsum auf. Differenziert nach Berufsgruppen zeigen vor allem Arbeitnehmer in Handwerksberufen sowie Manager und Führungskräfte einen hohen Alkoholkonsum. Die Arbeitnehmer in der jüngsten Altersgruppe (16 bis 24 Jährige) schlafen durchschnittlich etwas länger, im Vergleich zu den älteren Arbeitnehmern. Außerdem ist die Sporthäufigkeit in der jüngsten Altersgruppe am höchsten. Männliche Arbeitnehmer sowie Arbeitnehmer ohne Partner oder ohne Kinder treiben ebenfalls überduchschnittlich häufig Sport. Etwa 17% der Arbeitnehmer leidet unter Adipositas. Knapp 30% der Arbeitnehmer leidet manchmal oder häufiger an gesundheitlichen Problemen. Unter den gesundheitlichen Problemen sind Rückenprobleme besonders häufig, gefolgt von Schlafschwierigkeiten und Kopfschmerzen. Herzprobleme sind dagegen eher selten ausgeprägt. Arbeitnehmer mit Hochschulabschluss sowie Manager und Führungskräfte sind seltener von Gesundheitsproblemen betroffen. Gesundheitliche Probleme sind insgesamt mit Zigarettenkonsum, Schlafstunden pro Tag, Sporthäufigkeit und Body Mass Index assoziiert: Je weniger geraucht wird, je mehr geschlafen und Sport getrieben wird und je geringer das körperliche Gewicht der Arbeitnehmer, desto weniger Gesundheitsprobleme liegen tendenziell vor. [less ▲]

Detailed reference viewed: 41 (4 UL)
See detailThe economic programme of Emmanuel Macron
Chiocchetti, Paolo UL

E-print/Working paper (2017)

The outsider Emmanuel Macron is the winner of the first round of the French presidential election. His economic programme is betting on a strategy of fiscal consolidation, tax cuts, targeted investments ... [more ▼]

The outsider Emmanuel Macron is the winner of the first round of the French presidential election. His economic programme is betting on a strategy of fiscal consolidation, tax cuts, targeted investments, and further Europeanisation. Success crucially hinges on the outcome of the June legislative elections and on a favourable evolution of the global economic environment. [less ▲]

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See detailCharacterizations of quasitrivial symmetric nondecreasing associative operations
Devillet, Jimmy UL; Kiss, Gergely UL; Marichal, Jean-Luc UL

E-print/Working paper (2017)

In this paper we are interested in the class of n-ary operations on an arbitrary chain that are quasitrivial, symmetric, nondecreasing, and associative. We first provide a description of these operations ... [more ▼]

In this paper we are interested in the class of n-ary operations on an arbitrary chain that are quasitrivial, symmetric, nondecreasing, and associative. We first provide a description of these operations. We then prove that associativity can be replaced with bisymmetry in the definition of this class. Finally we investigate the special situation where the chain is finite. [less ▲]

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See detailScaling evidence of the homothetic nature of cities
Lemoy, Rémi UL; Caruso, Geoffrey UL

E-print/Working paper (2017)

In this paper we analyse the profile of land use and population density with respect to the distance to the city centre for the European city. In addition to providing the radial population density and ... [more ▼]

In this paper we analyse the profile of land use and population density with respect to the distance to the city centre for the European city. In addition to providing the radial population density and soil-sealing profiles for a large set of cities, we demonstrate a remarkable constancy of the profiles across city size. Our analysis combines the GMES/Copernicus Urban Atlas 2006 land use database at 5m resolu- tion for 300 European cities with more than 100.000 inhabitants and the Geostat population grid at 1km resolution. Population is allocated proportionally to surface and weighted by soil sealing and density classes of the Urban Atlas. We analyse the profile of each artificial land use and population with distance to the town hall. In line with earlier literature, we confirm the strong monocentricity of the European city and the negative exponential curve for population density. Moreover, we find that land use curves, in particular the share of housing and roads, scale along the two horizontal dimensions with the square root of city population, while population curves scale in three dimensions with the cubic root of city population. In short, European cities of different sizes are homothetic in terms of land use and population density. While earlier literature documented the scaling of average densities (total surface and population) with city size, we document the scaling of the whole radial distance profile with city size, thus liaising intra-urban radial analysis and systems of cities. In addition to providing a new empirical view of the European city, our scaling offers a set of practical and coherent definitions of a city, independent of its population, from which we can re-question urban scaling laws and Zipf’s law for cities. [less ▲]

Detailed reference viewed: 40 (1 UL)
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See detailHyperbolic ends with particles and grafting on singular surfaces
chen, qiyu; Schlenker, Jean-Marc UL

E-print/Working paper (2017)

We prove that any hyperbolic end with particles (cone singularities along infinite curves of angles less than π) admits a unique foliation by constant Gauss curvature surfaces. Using a form of duality ... [more ▼]

We prove that any hyperbolic end with particles (cone singularities along infinite curves of angles less than π) admits a unique foliation by constant Gauss curvature surfaces. Using a form of duality between hyperbolic ends with particles and convex globally hyperbolic maximal (GHM) de Sitter spacetime with particles, it follows that any convex GHM de Sitter spacetime with particles also admits a unique foliation by constant Gauss curvature surfaces. We prove that the grafting map from the product of Teichm\"uller space with the space of measured laminations to the space of complex projective structures is a homeomorphism for surfaces with cone singularities of angles less than π, as well as an analogue when grafting is replaced by "smooth grafting". [less ▲]

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See detailBenelux, Europe and the Cold War, the power of non-powers
Paravantis, Spero UL

E-print/Working paper (2017)

The conference “Benelux, Europe and the Cold War, the power of non-powers”, which took place on 30 and 31 March 2017 at the University of Luxembourg, was the first of three events planned in the FNR ... [more ▼]

The conference “Benelux, Europe and the Cold War, the power of non-powers”, which took place on 30 and 31 March 2017 at the University of Luxembourg, was the first of three events planned in the FNR-funded CORE junior project “Benelux”, as part of its public outreach and academic output objectives. The conference sought to highlight asymmetrical power relations in the Cold War period of European integration by examining European security. What was/is European security in the context of the Cold War? How was and is it conceived? What role did “non-powers” play in European security, and how did they help define it? This conference investigated these and other related questions by re-examining the US/European relationship in the early Cold War and the role that developments during this period played in the European integration movement. In so doing, the conference also showcased findings which helped unify historiographies of the Cold War and European integration. [less ▲]

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See detailUniversal Reasoning, Rational Argumentation and Human-Machine Interaction
Benzmüller, Christoph UL

E-print/Working paper (2017)

Classical higher-order logic, when utilized as a meta-logic in which various other (classical and non-classical) logics can be shallowly embedded, is well suited for realising a universal logic reasoning ... [more ▼]

Classical higher-order logic, when utilized as a meta-logic in which various other (classical and non-classical) logics can be shallowly embedded, is well suited for realising a universal logic reasoning approach. Universal logic reasoning in turn, as envisioned already by Leibniz, may support the rigorous formalisation and deep logical analysis of rational arguments within machines. A respective universal logic reasoning framework is described and a range of exemplary applications are discussed. In the future, universal logic reasoning in combination with appropriate, controlled forms of rational argumentation may serve as a communication layer between humans and intelligent machines. [less ▲]

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See detailWhat makes Data Science different? A discussion involving Statistics2.0 and Computational Sciences
Ley, Christophe; Bordas, Stéphane UL

E-print/Working paper (2017)

Data Science is today one of the main buzzwords be it in business, industrial or academic settings. Machine learning, experimental design, data-driven modelling are all, undoubtedly, rising disciplines if ... [more ▼]

Data Science is today one of the main buzzwords be it in business, industrial or academic settings. Machine learning, experimental design, data-driven modelling are all, undoubtedly, rising disciplines if one goes by the soaring number of research papers and patents appearing each year. The prospect of becoming a ``Data Scientist'' appeals to many. A discussion panel organised as part of the European Data Science Conference (European Association for Data Science (EuADS)) asked the question: ``What makes Data Science different?'' In this paper we give our own, personal and multi-facetted view on this question, from an engineering and a statistics perspective. In particular, we compare Data Science to Statistics and discuss the connection between Data Science and Computational Science. [less ▲]

Detailed reference viewed: 451 (30 UL)
See detailPopulation ageing [glossary]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

Population ageing is a major trend in contemporary European societies. A consequence of welcome shifts in life expectancy and fertility, it nevertheless entails important challenges for the adequacy ... [more ▼]

Population ageing is a major trend in contemporary European societies. A consequence of welcome shifts in life expectancy and fertility, it nevertheless entails important challenges for the adequacy, sustainability, and competitiveness of social and economic systems. [less ▲]

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See detailSudoses et inégalités sociales
Origer, Alain; Baumann, Michèle UL

E-print/Working paper (2017)

Des chercheurs du Ministère de la Santé (Dr. Alain ORIGER) et de l’unité de recherche INSIDE, Institut Santé & Comportement (Pr. Michèle BAUMANN et son équipe) ont publié récemment dans la revue ... [more ▼]

Des chercheurs du Ministère de la Santé (Dr. Alain ORIGER) et de l’unité de recherche INSIDE, Institut Santé & Comportement (Pr. Michèle BAUMANN et son équipe) ont publié récemment dans la revue scientifique PLoS ONE un article intitulé : A social gradient in fatal opioids and cocaine related overdoses ? Sélectionné par un jury d’experts internationaux, cet article a été primé au Scientific Award 2016 dans le cadre de l’European Monitoring Centre for Drugs and Drug Addiction.h ttps://insideblog.uni.lu/surdoses-et-inegalites-sociales/ [less ▲]

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See detailHow do inventor networks affect urban invention?
Berge, Laurent UL; Carayol, Nicolas; Roux, Pascale

E-print/Working paper (2017)

Social networks are expected to matter for invention in cities, but empirical evidence is still puzzling. In this paper, we provide new results on urban patenting covering more than twenty years of ... [more ▼]

Social networks are expected to matter for invention in cities, but empirical evidence is still puzzling. In this paper, we provide new results on urban patenting covering more than twenty years of European patents invented by nearly one hundred thousand inventors located in France. Elaborating on the recent economic literatures on peer effects and on games in social networks, we assume that the productivity of an inventor’s efforts is positively affected by the efforts of his or her partners and negatively by the number of these partners’ connections. In this framework, inventors’ equilibrium outcomes are proportional to the square of their network centrality, which encompasses, as special cases, several well-known forms of centrality (Degree, Katz-Bonacich, Page-Rank). Our empirical results show that urban inventors benefit from their collaboration network. Their production increases when they collaborate with more central agents and when they have more collaborations. Our estimations suggest that inventors’ productivity grows sublinearly with the efforts of direct partners, and that they incur no negative externality from them having many partners. Overall, we estimate that a one standard deviation increase in local inventors’ centrality raises future urban patenting by 13%. [less ▲]

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See detailTempered subanalytic topology on algebraic varieties
Petit, François UL

E-print/Working paper (2017)

On a smooth complex algebraic variety, we build the tempered subanalytic and Stein tempered subanalytic sites. We construct the sheaf of holomorphic functions tempered at infinity over these sites and ... [more ▼]

On a smooth complex algebraic variety, we build the tempered subanalytic and Stein tempered subanalytic sites. We construct the sheaf of holomorphic functions tempered at infinity over these sites and study their relations with the sheaf of regular functions, proving in particular that these sheaves are isomorphic on Zariski open subsets. We show that these data allow to define the functors of tempered and Stein tempered analytifications. We study the relations between these two functors and the usual analytification functor. We also obtain algebraization results in the non-proper case and flatness results. [less ▲]

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Peer Reviewed
See detailThe maximum number of systoles for genus two Riemann surfaces with abelian differentials
Judge, Chris; Parlier, Hugo UL

E-print/Working paper (2017)

This article explores the length and number of systoles associated to holomorphic $1$-forms on surfaces. In particular, we show that up to homotopy, there are at most $10$ systolic loops on such a genus ... [more ▼]

This article explores the length and number of systoles associated to holomorphic $1$-forms on surfaces. In particular, we show that up to homotopy, there are at most $10$ systolic loops on such a genus two surface and that the bound is realized by a unique translation surface up to homothety. We also provide sharp upper bounds on the the number of homotopy classes of systoles for a holomorphic $1$-form with a single zero in terms of the genus. [less ▲]

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See detailMigration, Labor Tasks and Production Structure in Europe
Joxhe, Majlinda UL; Borelli, Stefania; Giuseppe, De Arcangelis

E-print/Working paper (2017)

This paper assesses the effect of the immigration on the production structure in a selection of European countries in 2001-2009 with a task-based approach. The inflow of immigrants represents an increase ... [more ▼]

This paper assesses the effect of the immigration on the production structure in a selection of European countries in 2001-2009 with a task-based approach. The inflow of immigrants represents an increase in the relative supply of manual-physical (or simple) tasks, hence favoring simple-task intensive sectors. We use a new OECD dataset, PIAAC, to calculate the index of simple-task intensity at the country-industry level. The analysis confirms that the increase in migration stocks caused a positive impact on the value added of sectors that use more intensively simple tasks. These effects are more intense when considering countries as Italy and Spain characterized by a recent, rapid and intense inflow of migrants. Endogeneity issues are discussed and instruments based on a gravity approach are used in estimation. [less ▲]

Detailed reference viewed: 39 (6 UL)