Υποστηρικτική εργαλειοθήκη για εκπαιδευτικούς

E-print/Working paper (2020)

Στο πλαίσιο του έργου BMC-EU (Βασικές Κινητικές Δεξιότητες στην Ευρώπη) αναπτύχθηκε το πλαίσιο υποστήριξης και η υποστηρικτική εργαλειοθήκη βάση του μοντέλου των βασικών κινητικών δεξιοτήτων και των ... [more ▼]

Στο πλαίσιο του έργου BMC-EU (Βασικές Κινητικές Δεξιότητες στην Ευρώπη) αναπτύχθηκε το πλαίσιο υποστήριξης και η υποστηρικτική εργαλειοθήκη βάση του μοντέλου των βασικών κινητικών δεξιοτήτων και των αποτελεσμάτων από τη συλλογή δεδομένων κατά τη φάση 1 του έργου, το οποίο αποτελεί μέρος της πνευματικής παραγωγής 3. Ο σκοπός της εργαλειοθήκης αυτής είναι να εφαρμοστεί στα μαθήματα φυσικής αγωγής, ώστε να προσαρμοστούν κατάλληλα τόσο το περιεχόμενο όσο και οι μέθοδοι διδασκαλίας της φυσικής αγωγής. Ως πρώτο βήμα, το υποστηρικτικό πλαίσιο αναπτύχθηκε για τη διάγνωση των βασικών κινητικών δεξιοτήτων των μαθητών, καθώς και για την αξιολόγηση των δυνατοτήτων τους, ώστε στη συνέχεια να δημιουργηθούν συγκεκριμένα παρεμβατικά προγράμματα. Με βάση το πλαίσιο αυτό, αναπτύχθηκαν υποστηρικτικά φυλλάδια με τη μορφή της υποστηρικτικής εργαλειοθήκης, έτοιμα προς εφαρμογή σε συγκεκριμένες εκπαιδευτικές συνθήκες για την υποστήριξη μαθητών με πρόσθετες ανάγκες στις βασικές κινητικές δεξιότητες. Η υποστηρικτική εργαλειοθήκη περιλαμβάνει οδηγίες για την ερμηνεία των αποτελεσμάτων του MOBAK (Motorische Basiskompetenzen; Γερμανικά για τις βασικές κινητικές δεξιότητες), το πλαίσιο υποστήριξης ΜΟΒΑΚ, ένα γλωσσάρι, καθώς και την υποστηρικτική εργαλειοθήκη με εργαλεία για καθηγητές φυσικής αγωγής υπό τη μορφή καρτών περιγραφής διαδικασιών και καρτών δραστηριοτήτων ΜΟΒΑΚ, βασισμένα στις αρχές της παραλλαγής των δραστηριοτήτων και σε μία προσέγγιση προσανατολισμένη στις δεξιότητες. [less ▲]

On Reductions of Hintikka Sets for Higher-Order Logic

E-print/Working paper (2020)

Mitarbeiterorientiert führen – Wie ausgeprägt ist der transformationale Führungsstil in Luxemburg?

E-print/Working paper (2020)

Im Rahmen dieser Newsletter wird analysiert, in welchem Maße Vorgesetzte in Luxemburg einen transformationalen Führungsstil umsetzen. Vorgesetzte, die einen transformationalen Führungsstil ausüben, werden ... [more ▼]

Im Rahmen dieser Newsletter wird analysiert, in welchem Maße Vorgesetzte in Luxemburg einen transformationalen Führungsstil umsetzen. Vorgesetzte, die einen transformationalen Führungsstil ausüben, werden von ihren Mitarbeitern als fairer und unterstützender wahrgenommen. Insgesamt geht dieser Führungsstil einher mit als vorteilhafter erlebten Arbeitsbedingungen sowie einem erhöhten Well-Being der Mitarbeiter. Arbeitnehmer berichten dabei im Vergleich zu Arbeitnehmerinnen tendenziell über das Erleben eines höheren Ausmaßes an transformationalem Führungsstil ihres Vorgesetzten. Differenziert nach Beruf berichten vor allem Manager über ein überdurchschnittliches Ausmaß an transformationaler Führung ihres Vorgesetzten. [less ▲]

Deniable encryption, authentication, and key exchange

E-print/Working paper (2020)

We present some foundational ideas related to deniable encryption, message authentication, and key exchange in classical cryptography. We give detailed proofs of results that were previously only sketched ... [more ▼]

We present some foundational ideas related to deniable encryption, message authentication, and key exchange in classical cryptography. We give detailed proofs of results that were previously only sketched in the literature. In some cases, we reach the same conclusions as in previous papers; in other cases, the focus on rigorous proofs leads us to different formulations of the results. [less ▲]

Bitcoin Governance as a Decentralized Financial Market Infrastructure

E-print/Working paper (2020)

Bitcoin is the oldest and most widely established cryptocurrency network with the highest market capitalization among all cryptocurrencies. Although bitcoin (with lowercase b) is increasingly viewed as a ... [more ▼]

Bitcoin is the oldest and most widely established cryptocurrency network with the highest market capitalization among all cryptocurrencies. Although bitcoin (with lowercase b) is increasingly viewed as a digital asset belonging to a new asset class, the Bitcoin network (with uppercase B) is a decentralized financial market infrastructure (dFMI) that clears and settles transactions in its native asset without relying on the conventional financial market infrastructures (FMIs). To be a reliable asset class as well as a dFMI, however, Bitcoin needs to have robust governance arrangements; whether such arrangements are built into the protocol (i.e., on-chain governance mechanisms) or relegated to the participants in the Bitcoin network (i.e., off-chain governance mechanisms), or are composed of a combination of both mechanisms (i.e., a hybrid form of governance). This paper studies Bitcoin governance with a focus on its alleged shortcomings. In so doing, after defining Bitcoin governance and its objectives, the paper puts forward an idiosyncratic governance model whose main objective is to preserve and maximize the main value proposition of Bitcoin, i.e., its censorship-resistant property, which allows participants to transact in an environment with minimum social trust. Therefore, Bitcoin governance, including the processes through which Bitcoin governance crises have been resolved and the standards against which the Bitcoin Improvement Proposals (BIPs) are examined, should be analyzed in light of the prevailing narrative of Bitcoin as a censorship-resistant store of value and payment infrastructure. Within such a special governance model, this paper seeks to identify the potential shortcomings in Bitcoin governance by reference to the major governance crises that posed serious threats to Bitcoin in the last decade. It concludes that the existing governance arrangements in the Bitcoin network have been largely successful in dealing with Bitcoin’s major crises that would have otherwise become existential threats to the Bitcoin network. [less ▲]

Customary Land Conversion and the Formation of the African City

E-print/Working paper (2020)

As cities grow and spatially expand, agricultural land is converted into residential land. In many developing countries, especially in Sub-Saharan Africa, this process is accompanied by a change in land ... [more ▼]

As cities grow and spatially expand, agricultural land is converted into residential land. In many developing countries, especially in Sub-Saharan Africa, this process is accompanied by a change in land tenure, whereby plots held under traditional customary arrangements are sold to new urban residents, possibly with formal property rights. This paper studies joint land-use and land-tenure conversion in an urban economics model in which intermediaries purchase agricultural land from customary owners and attempt to transform it into residential plots with statutory property rights. The spatial equilibrium includes a mix of land uses and rights where statutory and non-statutory residential plots coexist with customary land that is mainly used for agriculture. Because customary ownership is subject to uncertainty (because of tenure insecurity), the conversion process includes a potential information asymmetry between customary owners and intermediaries. The analysis shows that a market failure may emerge whereby some customary owners prefer to continue farming their land rather than participate in the urban residential land market, which results in a city that is too small. Empirical analysis using Malian data validates the key features of the model captured by land price gradients, as well as the ranking and the variance of land prices, and is suggestive of the presence of information asymmetry. [less ▲]

Measuring Pants

E-print/Working paper (2020)

We investigate the terms arising in an identity for hyperbolic surfaces proved by Luo and Tan, namely showing that they vary monotonically in terms of lengths and that they verify certain convexity ... [more ▼]

We investigate the terms arising in an identity for hyperbolic surfaces proved by Luo and Tan, namely showing that they vary monotonically in terms of lengths and that they verify certain convexity properties. Using these properties, we deduce two results. As a first application, we show how to deduce a theorem of Thurston which states, in particular for closed hyperbolic surfaces, that if a simple length spectrum "dominates" another, then in fact the two surfaces are isometric. As a second application, we show how to find upper bounds on the number of pairs of pants of bounded length that only depend on the boundary length and the topology of the surface. [less ▲]

On immersions of surfaces into SL(2,C) and geometric consequences

E-print/Working paper (2020)

We approach the study of totally real immersions of smooth manifolds into holomorphic Riemannian space forms of constant sectional curvature -1. We introduce a notion of first and second fundamental form ... [more ▼]

We approach the study of totally real immersions of smooth manifolds into holomorphic Riemannian space forms of constant sectional curvature -1. We introduce a notion of first and second fundamental form, we prove that they satisfy a similar version of the classic Gauss-Codazzi equations, and conversely that solutions of Gauss-Codazzi equations are immersion data of some equivariant map. This study has some interesting geometric consequences: 1) it provides a formalism to study immersions of surfaces into SL(2,C) and into the space of geodesics of H^3; 2) it generalizes the classical theory of immersions into non-zero curvature space forms, leading to a model for the transitioning of hypersurfaces among H^n, AdS^n, dS^n and S^n; 3) we prove that a holomorphic family of immersion data corresponds to a holomorphic family of immersions, providing an effective way to construct holomorphic maps into the SO(n,C)-character variety. In particular we will point out a simpler proof of the holomorphicity of the complex landslide; 4) we see how, under certain hypothesis, complex metrics on a surface (i.e. complex bilinear forms of its complexified tangent bundle) of constant curvature -1 correspond to pairs of projective surfaces with the same holonomy. Applying Bers Double Uniformization Theorem to this construction we prove a Uniformization Theorem for complex metrics on a surface. [less ▲]

Fiscal effects of migrants in Europe: a quantile regression approach

E-print/Working paper (2020)

In this paper, we explore the fiscal impact of immigrants in Europe applying a quantile regression approach to data from the European Survey on Living Conditions (EU-SILC) for the period 2007-2015. Our ... [more ▼]

In this paper, we explore the fiscal impact of immigrants in Europe applying a quantile regression approach to data from the European Survey on Living Conditions (EU-SILC) for the period 2007-2015. Our estimations show that not only on average but also in almost all income quantiles, the fiscal position of both European and non-European migrants is not significantly different from that of native citizens. Furthermore, non-EU migrants are net contributors as compared to the corresponding native citizens in the Netherlands and Belgium for various quantiles. Lastly, we examine the link between migrants’ fiscal position and the fiscal perception of native European citizens measured using ESS data. We find a conflicting relationship: countries where migrants are perceived negatively are instead countries where they are net fiscal contributors and vice versa. [less ▲]

Fluctuations for matrix-valued Gaussian processes

E-print/Working paper (2020)

We consider a symmetric matrix-valued Gaussian process $Y^{(n)}=(Y^{(n)}(t);t\ge0)$ and its empirical spectral measure process $\mu^{(n)}=(\mu_{t}^{(n)};t\ge0)$. Under some mild conditions on the ... [more ▼]

We consider a symmetric matrix-valued Gaussian process $Y^{(n)}=(Y^{(n)}(t);t\ge0)$ and its empirical spectral measure process $\mu^{(n)}=(\mu_{t}^{(n)};t\ge0)$. Under some mild conditions on the covariance function of $Y^{(n)}$, we find an explicit expression for the limit distribution of $$Z_F^{(n)} := \left( \big(Z_{f_1}^{(n)}(t),\ldots,Z_{f_r}^{(n)}(t)\big) ; t\ge0\right),$$ where $F=(f_1,\dots, f_r)$, for $r\ge 1$, with each component belonging to a large class of test functions, and $$ Z_{f}^{(n)}(t) := n\int_{\R}f(x)\mu_{t}^{(n)}(\ud x)-n\E\left[\int_{\R}f(x)\mu_{t}^{(n)}(\ud x)\right].$$ More precisely, we establish the stable convergence of $Z_F^{(n)}$ and determine its limiting distribution. An upper bound for the total variation distance of the law of $Z_{f}^{(n)}(t)$ to its limiting distribution, for a test function $f$ and $t\geq0$ fixed, is also given. [less ▲]

A newform theory for Katz modular forms

E-print/Working paper (2020)

In this paper, a strong multiplicity one theorem for Katz modular forms is studied. We show that a cuspidal Katz eigenform which admits an irreducible Galois representation is in the level and weight old ... [more ▼]

In this paper, a strong multiplicity one theorem for Katz modular forms is studied. We show that a cuspidal Katz eigenform which admits an irreducible Galois representation is in the level and weight old space of a uniquely associated Katz newform. We also set up multiplicity one results for Katz eigenforms which have reducible Galois representation. [less ▲]

Robust ambiguity for contact tracing

E-print/Working paper (2020)

Automation, Growth, and Factor Shares in the Era of Population Aging

E-print/Working paper (2020)

How does population aging affect economic growth and factor shares in times of increasingly automatable production processes? The present paper addresses this question in a new macroeconomic model of ... [more ▼]

How does population aging affect economic growth and factor shares in times of increasingly automatable production processes? The present paper addresses this question in a new macroeconomic model of automation where competitive firms perform tasks to produce output. Tasks require labor and machines as inputs. New machines embody superior technological knowledge and substitute for labor in the performance of tasks. The incentive to automate is stronger if wages are higher. Automation is shown to boost the aggregate demand for labor if and only if the incentives to automate are strong enough and to reduce the labor share. These predictions obtain even though automation is labor-augmenting in the reduced-form production function. Population aging due to a higher longevity or a decline in fertility may strengthen or weaken the incentives to automate. Irrespective of its source, population aging is predicted to increase the growth rate of per-capita GDP in the short and in the long run. The short-run effect of higher longevity on the labor share is positive whereas the effect of a declining fertility is negative. In the long run, population aging reduces the labor share. [less ▲]

Single-cell sequencing of the human midbrain reveals glial activation and a neuronal state specific to Parkinson’s disease

E-print/Working paper (2020)

Parkinson’s disease (PD) etiology is associated with genetic and environmental factors that lead to a loss of dopaminergic neurons. However, the functional interpretation of PD-associated risk variants ... [more ▼]

Parkinson’s disease (PD) etiology is associated with genetic and environmental factors that lead to a loss of dopaminergic neurons. However, the functional interpretation of PD-associated risk variants and how other midbrain cells contribute to this neurodegenerative process are poorly understood. Here, we profiled >41,000 single-nuclei transcriptomes of postmortem midbrain tissue from 6 idiopathic PD (IPD) patients and 5 matched controls. We show that PD-risk variants are associated with glia- and neuron-specific gene expression patterns. Furthermore, Microglia and astrocytes presented IPD-specific cell proliferation and dysregulation of genes related to unfolded protein response and cytokine signalling. IPD-microglia revealed a specific pro-inflammatory trajectory. Finally, we discovered a neuronal cell cluster exclusively present in IPD midbrains characterized by CADPS2 overexpression and a high proportion of cycling cells. We conclude that elevated CADPS2 expression is specific to dysfunctional dopaminergic neurons, which have lost their dopaminergic identity and unsuccessful attempt to re-enter the cell cycle. [less ▲]

On the structure of symmetric $n$-ary bands

E-print/Working paper (2020)

We study the class of symmetric $n$-ary bands. These are $n$-ary semigroups $(X,F)$ such that $F$ is invariant under the action of permutations and idempotent, i.e., satisfies $F(x,\ldots,x)=x$ for all $x ... [more ▼]

We study the class of symmetric $n$-ary bands. These are $n$-ary semigroups $(X,F)$ such that $F$ is invariant under the action of permutations and idempotent, i.e., satisfies $F(x,\ldots,x)=x$ for all $x\in X$. We first provide a structure theorem for these symmetric $n$-ary bands that extends the classical (strong) semilattice decomposition of certain classes of bands. We introduce the concept of strong $n$-ary semilattice of $n$-ary semigroups and we show that the symmetric $n$-ary bands are exactly the strong $n$-ary semilattices of $n$-ary extensions of Abelian groups whose exponents divide $n-1$. Finally, we use the structure theorem to obtain necessary and sufficient conditions for a symmetric $n$-ary band to be reducible to a semigroup. [less ▲]

On Performance Characterization of Cascaded Multiwire-PLC/MIMO-RF Communication System

E-print/Working paper (2020)

Quality of Work – Project. Forschungsbericht zur Erhebungswelle 2019

E-print/Working paper (2020)

Der „Quality of Work Index Luxembourg“ (QoW)-Survey, der von der Universität Luxemburg und der luxemburgischen Chambre des Salariés konzipiert wurde, wurde 2019 zum siebten Mal durchgeführt. Ziel des ... [more ▼]

Der „Quality of Work Index Luxembourg“ (QoW)-Survey, der von der Universität Luxemburg und der luxemburgischen Chambre des Salariés konzipiert wurde, wurde 2019 zum siebten Mal durchgeführt. Ziel des Surveys ist es, die erlebte Arbeitssituation und -qualität luxemburgischer Arbeitnehmer zu erfassen. Der vorliegende Bericht dokumentiert die psychometrische Testung der Güte des aktuellen Erhebungsinstruments. In einem ersten Schritt erfolgt eine Beschreibung der Befragungsumstände sowie eine demographische Beschreibung der Stichprobe. Da die Erhebung 2019 als Mixed-Mode-Design – telefonische als auch Online-Befragung – durchgeführt wurde, wird auch analysiert, ob Stichprobenunterschiede zwischen den beiden Erhebungsmodi auftreten. Außerdem wird geklärt, ob es hinsichtlich demographischer Eigenschaften der Befragten, hinsichtlich der QoW-Skalen oder hinsichtlich verschiedener Well-Being-Maße zu systematischen Ausfällen seit der letzten Welle gekommen ist. Dann erfolgt eine Prüfung der Items der QoW-, der Beschäftigungsqualität- und der Well-Being-Skalen (fehlende Werte, verteilungsbeschreibender Maßzahlen, Balkendiagramme). In einem nächsten Schritt werden die Skalen mittels verschiedener Reliabilitätsstatistiken (Cronbach’s Alpha, Korrelationsanalysen der Items) sowie Koeffizienten zur Beschreibung der Skalenverteilung überprüft. Außerdem werden die Zusammenhänge der Skalen mittels Korrelationsanalysen überprüft. Im Anschluss daran wird die unterstellte Faktorenstruktur mittels konfirmatorischer Faktoren-analysen getestet. Die QoW- und Beschäftigungsqualität-Skalen werden außerdem auf verschiedene Well-Being-Skalen regressiert, um deren Relevanz für den QoW-Index zu prüfen. Ebenso werden einige Längsschnitt-Regressionsanalysen durchgeführt, um zu überprüfen ob einige Arbeitsbedingungen längerfristige Effekte auf das Well-Being der Arbeitnehmer aufweisen. Die QoW-Befragung 2019 hat außerdem das Schwerpunktthema „Leadership-Stil und Basic Needs“ behandelt. Die Güte der Skalen zu diesem Thema wird ebenfalls geprüft. Im Anschluss werden dann Korrelationen mit den QoW-, Beschäftigungsqualität- und Well-Being-Skalen berechnet. Abschließend wird das gesamte Erhebungsinstrument zusammenfassend diskutiert und Empfehlungen bezüglich zukünftiger Befragungen gegeben. [less ▲]

Secure Vehicular Communications through Reconfigurable Intelligent Surfaces

E-print/Working paper (2020)

The Structure of Behavioral Data

E-print/Working paper (2020)

For more than a century, scientists have been collecting behavioral data--an increasing fraction of which is now being publicly shared so other researchers can reuse them to replicate, integrate or extend ... [more ▼]

For more than a century, scientists have been collecting behavioral data--an increasing fraction of which is now being publicly shared so other researchers can reuse them to replicate, integrate or extend past results. Although behavioral data is fundamental to many scientific fields, there is currently no widely adopted standard for formatting, naming, organizing, describing or sharing such data. This lack of standardization is a major bottleneck for scientific progress. Not only does it prevent the effective reuse of data, it also affects how behavioral data in general are processed, as non-standard data calls for custom-made data analysis code and prevents the development of efficient tools. To address this problem, we develop the Behaverse Data Model (BDM), a standard for structuring behavioral data. Here we focus on major concepts in behavioral data, leaving further details and developments to the project's website (https://behaverse.github.io/data-model/). [less ▲]

A Welfare Evaluation of Green Urban Areas

E-print/Working paper (2020)

Urban green areas cover more than 6% of urban land in Europe. This paper quan-tifies the impact of urban green areas on city structures for more than 300 Europeancities. It discusses the economic effects ... [more ▼]

Urban green areas cover more than 6% of urban land in Europe. This paper quan-tifies the impact of urban green areas on city structures for more than 300 Europeancities. It discusses the economic effects of the local amenity produced by green urbanareas using an urban economics model with various set of preferences. It estimatesthose models using data on detailed residential land uses, green urban areas and popu-lation density. It finally assesses the economic effects of reducing urban green areas incounterfactual exercises where cities are closed and open to migration and green urbanland is converted to residential plots or not. By this strategy, the economic assess-ment accounts for the general equilibrium effects through endogenous land prices andresidential space and location choices. It shows that the gross benefits of urban greenareas are substantial. A uniform removal of half of the urban green areas is equivalentto 6-9% reduction of household annual income. However, the conversion of those areasto residential plots brings a net gain of approximately 4% [less ▲]

Digital Finance & The COVID-19 Crisis

E-print/Working paper (2020)

One Million or One Hundred Million Casualties? – The Impact of the COVID-19 Crisis on the Least Developed and Developing Countries

E-print/Working paper (2020)

Causal dynamical modelling predicts novel regulatory genes of FOXP3 in human regulatory T cells

E-print/Working paper (2020)

A Survey of Requirements for COVID-19 Mitigation Strategies. Part I: Newspaper Clips

E-print/Working paper (2020)

On the Sixth International Olympiad in Cryptography NSUCRYPTO

E-print/Working paper (2020)

The Gap and the Future: COVID-19 and (Digital) Collecting

E-print/Working paper (2020)

Radical entanglement for elliptic curves

E-print/Working paper (2020)

Let G be a commutative connected algebraic group over a number field K, let A be a finitely generated and torsion-free subgroup of G(K) of rank r>0 and, for n>1, let K(n^{−1}A) be the smallest extension ... [more ▼]

Let G be a commutative connected algebraic group over a number field K, let A be a finitely generated and torsion-free subgroup of G(K) of rank r>0 and, for n>1, let K(n^{−1}A) be the smallest extension of K inside an algebraic closure K¯ over which all the points P∈G(K¯) such that nP∈A are defined. We denote by s the unique non-negative integer such that G(K¯)[n]≅(Z/nZ)s for all n≥1. We prove that, under certain conditions, the ratio between nrs and the degree [K(n^{−1}A):K(G[n])] is bounded independently of n>1 by a constant that depends only on the ℓ-adic Galois representations associated with G and on some arithmetic properties of A as a subgroup of G(K) modulo torsion. In particular we extend the main theorems of [13] about elliptic curves to the case of arbitrary rank [less ▲]

FinTech for Financial Inclusion : A Framework for Digital Financial Transformation

E-print/Working paper (2020)

After Libra, Digital Yuan and COVID-19: Central Bank Digital Currencies and the New World of Money and Payment Systems

E-print/Working paper (2020)

Universal Hall conductance scaling in non-Hermitian Chern insulators

E-print/Working paper (2020)

Preservation of DNA Privacy During the Large Scale Detection of COVID-19

E-print/Working paper (2020)

Artificial Intelligence in Space

E-print/Working paper (2020)

Tasks, Technology, and Factor Prices in the Neoclassical Production Sector

E-print/Working paper (2020)

This paper introduces tasks into the neoclassical production sector. Competitive firms choose the profit-maximizing amounts of factor-specific tasks that determine their factor demands and output supplies ... [more ▼]

This paper introduces tasks into the neoclassical production sector. Competitive firms choose the profit-maximizing amounts of factor-specific tasks that determine their factor demands and output supplies. We show that the effect of factor-augmenting technical change on relative and absolute factor prices can be decomposed into a productivity effect and a task-demand effect of opposite sign. These effects appear since the novel task-based approach distinguishes between the demands for tasks and the demands for factors. This perspective provides a new intuition for the emergence of relative and absolute factor biases and the role of the elasticity of substitution. [less ▲]

Frobenius Extension II

E-print/Working paper (2020)

The first two sections of the paper provide a convenient scheme and additional diagrammatics for working with Frobenius extensions responsible for key flavors of equivariant SL(2) link homology theories ... [more ▼]

The first two sections of the paper provide a convenient scheme and additional diagrammatics for working with Frobenius extensions responsible for key flavors of equivariant SL(2) link homology theories. The goal is to clarify some basic structures in the theory and propose a setup to work over sufficiently non-degenerate base rings. The third section works out two related SL(2) evaluations for seamed surfaces. [less ▲]

Intersymbol and Intercarrier Interference in OFDM Systems: Unified Formulation and Analysis

E-print/Working paper (2020)

A unified matrix formulation is presented for the analysis of intersymbol and intercarrier interference in orthogonal frequency-division multiplexing (OFDM) systems. The proposed formulation relies on six ... [more ▼]

A unified matrix formulation is presented for the analysis of intersymbol and intercarrier interference in orthogonal frequency-division multiplexing (OFDM) systems. The proposed formulation relies on six parameters and allows studying various schemes, including those with windowing in the transmitter and/or in the receiver (called windowed OFDM systems), which may add cyclic suffix and/or cyclic prefix (CP), besides the conventional CP-OFDM. The proposed framework encompasses seven different OFDM systems. It considers the overlap-and-add procedure performed in the transmitter of windowed OFDM systems, being jointly formulated with the channel convolution. The intersymbol and intercarrier interference, caused when the order of the channel impulse response is higher than the number of CP samples, is characterized. A new equivalent channel matrix that is useful for calculating both the received signal and the interference power is defined and characterized. Unlike previous works, this new channel matrix has no restrictions on the length of the channel impulse response, which means that the study is not constrained to the particular case of two or three data blocks interfering in the received signal. Theoretical expressions for the powers of three different kinds of interference are derived. These expressions allow calculating the signal-to-interference-plus-noise ratio, useful for computing the data rate of each OFDM system. The proposed formulation is applied to realistic examples, showing its effectiveness through comparisons based on numerical performance assessments of the considered OFDM systems. [less ▲]

Normal approximation for functions of hidden Markov models

E-print/Working paper (2020)

A Blanket Too Narrow: On the Autonomy of Member States to Cut Particularly High Special Pensions

E-print/Working paper (2020)

Enquête transfrontalière sur le vécu de la littérature au lycée

E-print/Working paper (2020)

Assessing suppression strategies against epidemicoutbreaks like COVID-19: the SPQEIR model

E-print/Working paper (2020)

The current COVID-19 outbreak represents a most serious challenge for societies worldwide. It isendangering the health of millions of people, and resulting in severe socioeconomic challenges dueto lock ... [more ▼]

The current COVID-19 outbreak represents a most serious challenge for societies worldwide. It isendangering the health of millions of people, and resulting in severe socioeconomic challenges dueto lock-down measures. Governments worldwide aim to devise exit strategies to revive the economywhile keeping the pandemic under control. The problem is that the effects of distinct measures arenot well quantified. This paper compares several suppression approaches and potential exit strategiesusing a new extended epidemic SEIR model. It concludes that while rapid and strong lock-down isan effective pandemic suppression measure, a combination of other strategies such as social distanc-ing, active protection and removal can achieve similar suppression synergistically. This quantitativeunderstanding will support the establishment of mid- and long-term interventions. Finally, the paperprovides an online tool that allows researchers and decision makers to interactively simulate diversescenarios with our model. [less ▲]

Identifiability of Finite Mixture Models with underlying Normal Distribution

E-print/Working paper (2020)

In this paper, we show under which conditions generalized finite mixture with underlying normal distribution are identifiable in the sense that a given dataset leads to a uniquely determined set of model ... [more ▼]

In this paper, we show under which conditions generalized finite mixture with underlying normal distribution are identifiable in the sense that a given dataset leads to a uniquely determined set of model parameter estimations up to a permuta-tion of the clusters. [less ▲]

South Africa’s incomplete transition towards socio-economic justice: A case study on inequality and populism

E-print/Working paper (2020)

South Africa is currently one of the world’s most unequal countries, with massive income inequality, millions of people living in poverty without access to basic services and amenities, unemployment rates ... [more ▼]

South Africa is currently one of the world’s most unequal countries, with massive income inequality, millions of people living in poverty without access to basic services and amenities, unemployment rates consistently above 20% and the top 10% of the population receiving two thirds of the total income. Government economic policies on poverty reduction in the decades since the advent of democracy in South Africa in 1994 have been unable to eradicate the extreme racialised inequality which was the basis of the 342 years of colonialism and apartheid which were characterised by systematic dispossession and socio-economic marginalisation of South Africa’s majority Black population and the systematic privileging of the minority White population. While this history is not the primary focus of this paper, it nonetheless provides useful context. The paper’s primary focus is on the more recent normative and legal challenges of post-1994 South Africa that have resulted in further entrenching socio-economic inequality and contributing to the rise of populism. In this paper we argue that the dire living conditions of a large proportion of the population and disillusionment with the State’s ability to deliver on its promises in this regard, along with the poor implementation of social and economic rights have led to the development of a populist culture in South African politics. [less ▲]

Supersingular Isogeny-Based Designated Verifier Blind Signature

E-print/Working paper (2019)

Profit taxation and royalties: evidence from gold mines in Sub-Saharan Africa

E-print/Working paper (2019)

In this paper, we analyze theoretically and empirically the effects of tax changes on firms’ profits in extractive industries. In the theoretical part, we assume a country that levies a profit tax and a ... [more ▼]

In this paper, we analyze theoretically and empirically the effects of tax changes on firms’ profits in extractive industries. In the theoretical part, we assume a country that levies a profit tax and a royalty on the profits of extractive firms to maximize its tax revenues. The mining companies may reduce their taxable income by cost manipulation. By analyzing the optimal choice of the government and of the firms, we first establish the optimal tax policy and then we investigate the impact of the optimal fiscal policy on firms’ profits. In the empirical part of the paper, we estimate the effect of the profit tax and royalty on the extracting firms’ profit in African countries during the period spanning from 2007 to 2018. We use the Mining Intelligence database to constitute a panel of annual individual data from a database of 363 gold mines located in 21 Sub-Saharan countries. We obtain an inverse relationship between the tax rate change of the two tax instruments and the profit of the firms. [less ▲]

A note on a quantization via the Ran space

E-print/Working paper (2019)

L'espace sportif européen: circulations, organisations et identité européenne

E-print/Working paper (2019)

Dès la fin du xixe siècle, l’espace européen est le cadre d’un développement précoce des échanges sportifs et tient un rôle pionnier dans l’organisation internationale des sports. L’homogénéisation des ... [more ▼]

Dès la fin du xixe siècle, l’espace européen est le cadre d’un développement précoce des échanges sportifs et tient un rôle pionnier dans l’organisation internationale des sports. L’homogénéisation des pratiques et la mise en place de compétitions continentales, processus commencé dans l’entre-deux-guerres et qui se renforce après la Deuxième Guerre mondiale, a comme effet la constitution d’un espace sportif européen. Touchant autant les élites que les masses et le produit d’une intense médiatisation, les sports ont un impact qui dépasse largement les stades et permettent aux Européens de se rencontrer et in fine de mieux se connaître. [less ▲]

The Whistleblower’s Protection Directive: Reinforcing Transparency and Accountability at the EU Level

E-print/Working paper (2019)

Distant Justice Symposium: Phil Clark’s ‘Distant Justice’–A Wake-Up Call for the International Criminal Court or a Case for Managing Expectations?

E-print/Working paper (2019)

Projective and conformal closed manifolds with a higher-rank lattice action

E-print/Working paper (2019)

We prove global results about actions of cocompact lattices in higher-rank simple Lie groups on closed manifolds endowed with either a projective class of connections or a conformal class of pseudo ... [more ▼]

We prove global results about actions of cocompact lattices in higher-rank simple Lie groups on closed manifolds endowed with either a projective class of connections or a conformal class of pseudo-Riemannian metrics of signature (p,q), with min(p,q)>1. In the continuity of a recent article, provided that such a structure is locally equivalent to its model X, the main question treated here is the completeness of the associated (G,X)-structure. The similarities between the model spaces of non-Lorentzian conformal geometry and projective geometry make that lots of arguments are valid for both cases, and we expose the proofs in parallel. The conclusion is that in both cases, when the real-rank is maximal, the manifold is globally equivalent to either the model space X or its double cover. [less ▲]

Advocate General Bobek on One of us – Legal Clarity vs Political Debate

E-print/Working paper (2019)

Now is (not yet) the Winter of Our Discontent: The Unfulfilled Promise of Economic and Social Rights in the Fight Against Economic Inequality

E-print/Working paper (2019)

Material inequality or (extreme) economic inequality has been touted as one of the greatest challenges of the twenty-first century. Wealth is “hemorrhaging upwards” rather than “trickling down.” In a ... [more ▼]

Material inequality or (extreme) economic inequality has been touted as one of the greatest challenges of the twenty-first century. Wealth is “hemorrhaging upwards” rather than “trickling down.” In a world where the rich get richer, the poor get poorer, and the inequality gap in income and wealth continues intensifying at an alarming pace, there exists an “inequality explosion” that threatens the very fabric of our global society. While economic inequality and questions of (re)distribution of wealth and income have traditionally been examined within the spheres of development law and political economy, I argue that a human rights based approach that contains economic and social rights (hereinafter, ESRs) at its core is capable of mitigating economic inequality. International human rights norms enjoy a high level of global legitimacy, as evidenced by the fact that the key human rights instruments have been widely accepted in all regions of the world. 169 States have ratified the International Covenant on Economic, Social and Cultural Rights (hereinafter, ICESCR). Underpinned by universally recognized moral values and reinforced by national and international legal obligations, ESRs therefore provide a compelling normative framework through which material inequality can be addressed. [less ▲]