An Experimental Analysis of Optimal Renewable Resource Management:The Fishery

E-print/Working paper (2008)

Loss Functions in Option Valuation: A Framework for Selection

E-print/Working paper (2008)

La production en verre et cristal dans la Grande Région SaarLorLux

E-print/Working paper (2008)

Since the beginning of the 15th century, glassmaking has been one of the most important and dynamic production sectors in the Greater Region. Located in the heart of Europe and divided between German and ... [more ▼]

Since the beginning of the 15th century, glassmaking has been one of the most important and dynamic production sectors in the Greater Region. Located in the heart of Europe and divided between German and French influences, the glassworks represented (and still represent today) a major geopolitical stake. Despite conditions made difficult by successive wars and border shifts, some of the most important glass and crystal factories in Europe in terms of size, activity and innovation were created from the 18th century onwards. [less ▲]

Familiennamen aus der Berufsbezeichnung für den Glaser

E-print/Working paper (2008)

Die Karte stellt die Verbreitung der Varianten des Familiennamens Glesener / Glaser / Glasmacher in der Großregion SaarLorLux dar. Sie ist ein Beispiel für Ergebnisse des FNR-Projektes "Luxemburgischer ... [more ▼]

Die Karte stellt die Verbreitung der Varianten des Familiennamens Glesener / Glaser / Glasmacher in der Großregion SaarLorLux dar. Sie ist ein Beispiel für Ergebnisse des FNR-Projektes "Luxemburgischer Familiennamenatlas" (LFA, Peter Gilles). Der Teilraum Lothringen ist bisher noch unberücksichtigt. Das Ziel des "Luxemburgischen Familiennamenatlas" (LFA) besteht darin, die Verbreitung der Familiennamen in Luxemburg und in den Nachbarregionen zu dokumentieren, um in einem zweiten Schritt eventuelle Rückschlüsse auf die Sprach- und Siedlungsgeschichte und auf Phänomene des historischen Sprachkontakts schließen zu können. Auch soll herausgefunden werden, welche Familiennamen typisch für Luxemburg sind und ob bzw. worin sich diese von Namen in anderen Untersuchungsgebieten unterscheiden. [less ▲]

Glas- und Kristallerzeugung in der Großregion SaarLor-Lux

E-print/Working paper (2008)

Die Kunst des Glasmachens gehört seit dem Beginn des 15. Jahrhunderts zu den wichtigsten und erfolgreichsten Industriezweigen der Großregion. Die für die Glasherstellung benötigten Rohstoffe waren im ... [more ▼]

Die Kunst des Glasmachens gehört seit dem Beginn des 15. Jahrhunderts zu den wichtigsten und erfolgreichsten Industriezweigen der Großregion. Die für die Glasherstellung benötigten Rohstoffe waren im Überfluss vorhanden, die jeweiligen Landesherren förderten die Ansiedlung der Glasmacher. Von Südlothringen aus verbreitete sich die Kunst des Glasmachens in Richtung Norden, an die Saar und nach Wallonien. Eine besondere Herausforderung für Regierende, Unternehmer (Investoren) und Arbeiter bedeutet(e) die geopolitische Lage der Glashütten im Herzen Europas, zwischen deutschem und französischem Einflussbereich. Trotz der durch zahlreiche Kriege und Grenzverschiebungen erschwerten Bedingungen entstanden am Westrand der Vogesen, im Bitscher Land, an der Saar und in Wallonien ab dem 18. Jahrhundert einige der wichtigsten, größten und innovativsten Glas- und Kristallglashütten Europas. Einige von ihnen setzen bis heute weltweit Qualitätsmaßstäbe in Handwerk und Design. [less ▲]

Aufschwung und Niedergang des Steinkohlenbergbaus in der Großregion SaarLorLux

E-print/Working paper (2008)

Die Karte zeigt die Verbreitung der ehemaligen Steinkohlengruben der Großregion in der wallonischen und der saarländisch-lothringischen Lagerstätte von etwa 1800 bis heute. Nach der Schließung des letzten ... [more ▼]

Die Karte zeigt die Verbreitung der ehemaligen Steinkohlengruben der Großregion in der wallonischen und der saarländisch-lothringischen Lagerstätte von etwa 1800 bis heute. Nach der Schließung des letzten wallonischen Bergwerks Sainte Catherine du Roton 1984 und des letzten Lothringer Bergwerks La Houve 2004 endete 2012 mit der Stilllegung des Bergwerks Saar in Ensdorf der Steinkohlenbergbau in der Großregion SaarLorLux endgültig. Insgesamt wurden in den wallonischen Revieren über die Jahrhunderte rund 2 Mrd. t Kohle gefördert, im Saarland 1,5 Mrd. t und in Lothringen 800 Mio. t. [less ▲]

Applying the Varieties of Capitalism Approach to Higher Education. A Case Study of the Internationalisation Strategies of German and British Universities

E-print/Working paper (2008)

In recent years the global market for higher education has expanded rapidly while internationalisation strategies have been developed at university, national, as well as European levels, all with the aim ... [more ▼]

In recent years the global market for higher education has expanded rapidly while internationalisation strategies have been developed at university, national, as well as European levels, all with the aim to increase the competitiveness of higher education institutions. This paper asks how different institutional settings explain distinct national patterns found in the internationalisation of universities, observed to be based largely on either market coordination or strategic interaction of the involved actors. Existing concepts from the Varieties of Capitalism literature, such as institutional complementarity and comparative institutional advantage, are introduced to the comparative study of higher education systems and applied to develop a theoretical framework for an institutional analysis of university strategies in the global market for higher education. In a case study, the analytical framework is then deployed to contrast the internationalisation of universities in Germany and the United Kingdom. The internationalisation processes reflect the mode of coordination in the respective higher education systems and national models of capitalism. Further insights are that the conceptual toolbox of the Varieties of Capitalism approach can be fruitfully applied to higher education, and that it is possible to enhance the framework by adding the state as a significant factor in differentiation. [less ▲]

On maximal independent sets in circulant digraphs

E-print/Working paper (2007)

In this research note we introduce St-Nicolas graphs, i.e. circulant digraphs showing exactly n maximal independent sets, isomorph under the digraph’s automorphisms group. This class of digraphs represent ... [more ▼]

In this research note we introduce St-Nicolas graphs, i.e. circulant digraphs showing exactly n maximal independent sets, isomorph under the digraph’s automorphisms group. This class of digraphs represent a generalisation of Andrásfai graphs with interesting links to finite group theory. [less ▲]

Naturräumliche Gliederung der Großregion SaarLorLux

E-print/Working paper (2007)

The paper shows and explains the natural classification of the Greater Region SaarLorLux, following a consistent concept. The natural regions, their main groups as well as the natural space units, were ... [more ▼]

The paper shows and explains the natural classification of the Greater Region SaarLorLux, following a consistent concept. The natural regions, their main groups as well as the natural space units, were created according to the concept of Meynen & Schmithüsen (1953-1962). [less ▲]

Relative Performance Evaluation, Risk Aversion and Entry

E-print/Working paper (2007)

Financial versus Social Efficiency of Corporate Bankruptcy Law: the French Dilemma ?

E-print/Working paper (2007)

The financing of the European Union

E-print/Working paper (2007)

The European Union is a unique and exceptional organisation in many respects. Its financial system, whose rules and structure are very different from those of national budgetary law, has changed a great ... [more ▼]

The European Union is a unique and exceptional organisation in many respects. Its financial system, whose rules and structure are very different from those of national budgetary law, has changed a great deal and is still changing. The most significant changes include: — The unification of budgetary instruments. Initially, each Community had its own budget or budgets (administrative and operating). These have now been replaced by a single budget, the general budget of the European Union. — Progress towards financial autonomy. Following the example of the ECSC, which was financed by real ‘tax revenue’ from the time it was set up, the EEC and Euratom changed to a system of own resources on 1 January 1971. — Reform of the Community financial system. The financial perspective, a genuine multiannual financial framework and instrument of budgetary discipline, was introduced in 1988. It forms an integral part of an interinstitutional agreement between Parliament, the Council and the Commission. — The pursuit of an institutional balance between the Council, Parliament and the Commission in the exercise of budgetary power. Initially, budgetary power lay solely with the Council. Parliament and the Council subsequently became the two arms of budgetary authority. The Commission retains a right to propose legislation in that sphere. The development of the financial system of the European Union superstructure is testament to its extremely varied history encompassing five decades and six enlargements. [less ▲]

Les institutions hospitalières médiévales dans la Grande Région SaarLorLux (de 600 à 1500)

E-print/Working paper (2007)

In the area between the Meuse and the Rhine, between Aachen and Basel, there were some 528 different hospitals between 600 and 1500, even if they did not all function at the same time. By hospitals we ... [more ▼]

In the area between the Meuse and the Rhine, between Aachen and Basel, there were some 528 different hospitals between 600 and 1500, even if they did not all function at the same time. By hospitals we mean hostels for pilgrims and travellers, poorhouses, clinics, monastery infirmaries, maternity wards, orphanages, old people's homes, old people's homes for the wealthy etc. The map summarises the results of the author's habilitation thesis on "Hospitals between the Meuse and the Rhine in the Middle Ages. Typological, topographical, functional and spiritual aspects'. [less ▲]

Autoindustrie in der Großregion SaarLorLux 2007 - Produktion, Forschung, Ausbildung

E-print/Working paper (2007)

Die Automobilindustrie gilt in der Großregion als wichtiger Pfeiler des wirtschaftlichen Strukturwandels. Eine Vielzahl teils hoch spezialisierter Zulieferer und Dienstleister prägt heute die ... [more ▼]

Die Automobilindustrie gilt in der Großregion als wichtiger Pfeiler des wirtschaftlichen Strukturwandels. Eine Vielzahl teils hoch spezialisierter Zulieferer und Dienstleister prägt heute die Unternehmenslandschaft und stellt einen Großteil der industriellen Arbeitsplätze. Die Karte zeigt alle Betriebe des Sektors ab 500 Beschäftigten im Jahr 2007. Aufgrund der durch die Allgemeine Wirtschaftskrise ab 2008 aufgetretenen tief greifenden Veränderungen der Branche wurde dieser Beitrag durch einen zweiten, ausführlicheren Beitrag zur Autoindustrie der Großregion 2011 (C.K. Hahn, GR-Atlas Vol. 27) ergänzt. [less ▲]

Gestes, pratiques, corporéité et polyfocalisation de l’action dans le travail de techniciennes de surface.

E-print/Working paper (2007)

Evaluation des performances relatives, risque et entrée

E-print/Working paper (2006)

Tax competition, location and horizontal foreign direct investment

E-print/Working paper (2005)

We develop a model of capital tax competition in which imperfectly competitive firms choose both the number of plants they operate and their location. When compared to models with single-plant firms, the ... [more ▼]

We develop a model of capital tax competition in which imperfectly competitive firms choose both the number of plants they operate and their location. When compared to models with single-plant firms, the presence of multinationals reverses some standard results. First, instead of being subsidized, capital may actually be taxed in equilibrium, which shows that the presence of taxable ‘multinational rents’ relaxes tax competition. Second, even when firms are subsidized, their subsidyinclusive profits may be decreasing in subsidies, due to fiercer price competition by more multinationals. Third, multinationals may give rise to multiple equilibria in the tax game, one of which can be a ‘subsidy trap’ characterized by many multinationals, high subsidy levels, and low welfare. [less ▲]

Theories of Knowledge. Is a naturalised epistemology bound to leave unanswered some important epistemological questions?

E-print/Working paper (2005)

Regulation of the Market for Standard Software: Waving Goodbye to 'Efficiency'?

E-print/Working paper (2005)

The market for standard software shows an inexorable tendency towards concentration. Whereas such a development might be considered efficient due to the market's nature as a natural monopoly, it could ... [more ▼]

The market for standard software shows an inexorable tendency towards concentration. Whereas such a development might be considered efficient due to the market's nature as a natural monopoly, it could also require stronger regulation, similar to other concentrated industries. This paper analyzes to what extent the existing legal frameworks under U.S. and European intellectual property and antitrust law mitigate pro-concentration effects. It characterizes the standard software market as an industry in need of regulation and reconsiders the current efficiency-focused approach in favor of measures that strengthen competition as a source of rivalry. Rather than considering efficiency arguments as "all-or-nothing" justification for otherwise anti-competitive conduct, as under the Chicago School concept, the concept proposed in this paper considers the "efficiency" criterion to merely limit the remedies imposed by adjudicators. [less ▲]

Explicit and Implicit System of Corporate Control – A Convergence Theory of Shareholder Rights

E-print/Working paper (2004)

Part B. of the paper compares the basic concepts of shareholder control in Anglo-America and some states of Continental Europe. It introduces a new categorization between Implicit and Explicit Systems of ... [more ▼]

Part B. of the paper compares the basic concepts of shareholder control in Anglo-America and some states of Continental Europe. It introduces a new categorization between Implicit and Explicit Systems of Corporate Control. The first category refers to statutes that are enacted and construed with the belief that market forces influence managers. Shareholder rights to be exercised in direct contact with the corporation are thought to be relatively weak. This system is established in the Anglo-American world. In contrast, direct shareholder influence through voting and (even minority) shareholder monitoring constitute the fundaments of the Explicit System that traditionally prevailed, for example, in France and Germany. This paper provides historical, statutory and new empirical evidence from some Continental jurisdictions, and in particular Germany. It concludes that in Germany, shareholder meetings are part of Corporate Governance, while the Anglo-American corporate world traditionally understood this term to include only inter-board relationships. Part C. analyses the questions of whether, how and why Corporate Governance systems converge. This study suggests that Corporate Governance systems are likely to develop in Convergence Cycles: If a legal regime provides a particularly efficient solution to a specific problem, this solution will eventually be adopted by other Corporate Governance systems with an inferior system in respect of such problem. These Convergence Cycles will finally overcome the forces against formal convergence. The proposition of Convergence Cycles draws on historical, as well as new statutory and empirical evidence, collected by the author. Part D., finally, analyses the likely impact of convergence on ownership structures. It is likely that the answer to the question of which ownership structure is efficient depends on the stage of the business cycle that the firm is at. Firms within the same stage are likely to become more and more similar with respect to their ownership structures, until they reach an equilibrium that is set at a specific point for a particular group of firms. Thus, this paper adds a dynamic perspective to the static views that presently prevail in the debate upon the convergence of ownership structures. [less ▲]

Competition over piratable goods

E-print/Working paper (2004)

The effects of (private, small-scale) copying on the pricing behavior of producers of information goods are studied within a unified model of vertical differentiation. Although information goods are ... [more ▼]

The effects of (private, small-scale) copying on the pricing behavior of producers of information goods are studied within a unified model of vertical differentiation. Although information goods are assumed to be perfectly horizon tally differentiated, demands are interdependent because the copying technology exhibits increasing returns to scale. We characterize the symmetric Nash equilibria of the pricing game played by n producers of information goods. We show thereby how the producers' attitudes towards piracy are interdependent and evolve with the relative attractiveness of copies. [less ▲]

Marco-level analysis of food-supply chain dynamics and diversity: An overview for Germany

E-print/Working paper (2003)

This document is analysing the development and the state-of-the-art of food-supply chains in Germany.

The credibility of expert advice for regulatory decision-making in the US and EU

E-print/Working paper (2002)

Impact de l’attrait des places bancaires sur les taux d’intérêt créditeurs : Un modèle de formation des taux créditeurs estimé sur données en panel de banques européennes

E-print/Working paper (2001)

This article evaluates the impact of banking centers' attractiveness on deposit interest rates. Using balance-sheet data from a set of 135 banks, the authors test an intermediation model of deposit rate ... [more ▼]

This article evaluates the impact of banking centers' attractiveness on deposit interest rates. Using balance-sheet data from a set of 135 banks, the authors test an intermediation model of deposit rate determination. In particular, the investigation shows a significant impact of « confidentiality » on deposit rates, thus confirming the importance of qualitative variables favouring local differentiation and clustering of banking activities. [less ▲]

Daten und Fakten zu Migrantenjugendlichen an Sonderschulen in der Bundesrepublik Deutschland

E-print/Working paper (2001)

Zwischen 1965 und 1994 hat sich die Zahl der nichtdeutschen Schüler/innen in der Bundesrepublik Deutschland verzwanzigfacht. Seit dem Jahr 1991 gehen mehr als eine Million Schüler/innen mit ... [more ▼]

Zwischen 1965 und 1994 hat sich die Zahl der nichtdeutschen Schüler/innen in der Bundesrepublik Deutschland verzwanzigfacht. Seit dem Jahr 1991 gehen mehr als eine Million Schüler/innen mit ausländischem Pass in (west-)deutsche Schulen; d.h. circa jede/r zehnte Schüler/in hat eine nichtdeutsche Staatsangehörigkeit. Über diese zahlenmäßige Präsens hinaus bieten die Vergleiche zwischen deutschen und nichtdeutschen Schülern/innen allgemein und zwischen deutschen und nichtdeutschen Sonderschülern/innen eine Perspektive, welche die Herausforderungen des Bildungssystems der Bundesrepublik Deutschland in ihrer Institutionalisierung und Expansion darstellt. Gleichzeitig stellen „in der BRD (...) die Ausländerkinder eine Gruppe dar, der im Bildungswesen besondere Aufmerksamkeit gewidmet werden muß, wenn sie nicht schulisch erheblich benachteiligt werden soll“ (Arbeitsgruppe Bildungsbericht am MPIB, 1994: 364). Von 1970 bis 1979 stieg der Anteil nichtdeutscher Schüler/innen an den Sonderschulen im Vergleich zu den Schülern insgesamt kontinuierlich an (Trommer/Köhler 1981: 130). Dieser Trend setzte sich fort, so dass bis 1999 nahezu 15% aller Sonderschüler/innen nichtdeutscher Herkunft waren, obwohl Schüler/innen nichtdeutscher Herkunft nur 9,4% aller Schüler/innen in der Bundesrepublik ausmachten. Das bedeutet für 1999 eine Überrepräsentanz ausländischer Kinder und Jugendlicher an deutschen Sonderschulen von 1,56. Parallel dazu zeigen die folgenden Analysen eine hohe Varianz zwischen den Bundesländern in der Sonderschulzuweisung nichtdeutscher Schüler/innen sowie unter den europäischen Nationalitäten (im Schuljahr 1998/99: von 0,5% bis hin zu 13,6%). Zugleich gibt es historisch Verschiebungen in der Begründung des Förderbedarfs zwischen dem größten Förderschwerpunkt „Lernen“ (von 82% auf 54% zwischen 1970-98) und anderen Kategorien des Förderbedarfs, die an Bedeutung gewonnen haben. Regionale Unterschiede in der Verteilung von Migrantenjugendlichen unter den einzelnen Sonderschularten sind u.a. Ausdruck der Differenzen in der Bildungs- bzw. Schulpolitik der Länder. So existieren große Unterschiede in der Akzeptanz integrativer pädagogischer Ansätze und Konzepte, der Ausbildung der Lehrer/innen und in der historischen Entwicklung verschiedener Schulformen. Die Existenz von Hauptschulen und Sonderschulen als quasi „untere bzw. separate Bildungsgänge“ sowie die Veränderung ihrer Schülerschaft in Folge der Bildungsexpansion und eine allgemein höhere Bildungsbeteiligung resultieren unter anderem darin, dass zwei von zehn nichtdeutschen Schulentlassenen die Schule ohne Hauptschulabschluss verlassen und deren „Misserfolgsquote“ immer noch ca. 2,5-mal so hoch ist wie bei den deutschen Jugendlichen (Solga 2001). Um die ausgewiesenen Ergebnisse zu Jugendlichen mit Migrationshintergrund an deutschen Sonderschulen adäquat einordnen zu können, werden in diesem Arbeitspapier auch ausgewählte Daten und Fakten zur allgemeinen Bildungsbeteiligung von Jugendlichen ausländischer Herkunft dargestellt und es wird auf demographische Schlüsseldaten eingegangen. Insgesamt zeigen die im Folgenden dargestellten Zahlen deutlich, dass—wie es heute in der Politik und den Medien nun endlich reflektiert wird—Jugendliche nichtdeutscher Herkunft im deutschen Bildungssystem benachteiligt sind und man immer noch versucht, ihre „Lernbehinderung“—die zum Großteil auch auf eine gesellschaftliche „Lernblockierung“ zurückgeht—mittels Sonder- bzw. Förderschulen und damit mittels institutioneller Separierung statt Integration zu lösen. [less ▲]

On perfect, amicable, and sociable chains

E-print/Working paper (2000)

Let $\bfx = (x_0,\ldots,x_{n-1})$ be an $n$-chain, i.e., an $n$-tuple of non-negative integers $< n$. Consider the operator $s: \bfx \mapsto\bfx' = (x'_0,\ldots,x'_{n-1})$, where $x'_j$ represents the ... [more ▼]

Let $\bfx = (x_0,\ldots,x_{n-1})$ be an $n$-chain, i.e., an $n$-tuple of non-negative integers $< n$. Consider the operator $s: \bfx \mapsto\bfx' = (x'_0,\ldots,x'_{n-1})$, where $x'_j$ represents the number of $j$'s appearing among the components of $\bfx$. An $n$-chain $\bfx$ is said to be perfect if $s(\bfx) = \bfx$. For example, (2,1,2,0,0) is a perfect 5-chain. Analogously to the theory of perfect, amicable, and sociable numbers, one can define from the operator $s$ the concepts of amicable pair and sociable group of chains. In this paper we give an exhaustive list of all the perfect, amicable, and sociable chains. [less ▲]

Review of a BBS target article Lexical Entries and Rules of Language: A Multidisciplinary Study of German Inflection by Harald Clahsen to appear in BBS (1999) 22 (6)

E-print/Working paper (1999)

Many authors (e.g., Chomsky 1995, Pinker 1984, and Marcus 1998) argue that the architecture of the language faculty contains two separate components: a (structured) lexicon and a computational component ... [more ▼]

Many authors (e.g., Chomsky 1995, Pinker 1984, and Marcus 1998) argue that the architecture of the language faculty contains two separate components: a (structured) lexicon and a computational component. Clahsen presents in a current BBS target article (in press) new empirical evidences in favour of such a dual-mechanism model of language processing based on a multidisciplinary study of German inflection. In the following review, I will summarise and discuss the major points of Clahsen's paper. My focus will be on theoretical, methodological and empirical issues presented and discussed in the paper. An important issue will be the bearing of his empirical findings on the current debate in psycholinguistic modelling. I will as well speculate that at least a part of Clahsen's reasoning seems not to hold in the case of a language closely related to German, namely Luxembourgian. [less ▲]

On linear decompositions of L-valued simple graphs

E-print/Working paper (-)

In this report we will present a linear decomposition of a given L- valued binary relation into a set of sub-relations of kernel-dimension one. We will apply this theoretical result to the design of a ... [more ▼]

In this report we will present a linear decomposition of a given L- valued binary relation into a set of sub-relations of kernel-dimension one. We will apply this theoretical result to the design of a faster algorithm for computing L-valued kernels on general L-valued simple graphs. [less ▲]

Le français langue seconde dans les écoles maternelles et primaires de la République de Vanuatu (Pacifique Sud), Bilan d’une année d’étude dans le cadre de la « bourse d‘excellence postdoctorale Aupelf-Uref »

E-print/Working paper (1995)

Effective Kummer Theory for Elliptic Curves

E-print/Working paper (n.d.)

Let E be an elliptic curve defined over a number field K, let α ∈ E(K) be a point of infinite order, and let N −1 α be the set of N -division points of α in E(K). We prove strong effective and uniform ... [more ▼]

Let E be an elliptic curve defined over a number field K, let α ∈ E(K) be a point of infinite order, and let N −1 α be the set of N -division points of α in E(K). We prove strong effective and uniform results for the degrees of the Kummer extensions [K(E[N ], N −1 α) : K(E[N ])]. When K = Q, and under a minimal (necessary) assumption on α, we show that the inequality [Q(E[N ], N −1 α) : Q(E[N ])] ≥ cN 2 holds with a constant c independent of both E and α. [less ▲]

A conjecture on primes in arithmetic progressions and geometric intervals

E-print/Working paper (n.d.)

We conjecture that any interval of the form [q^t ,q^(t+1) ], where q≥ 2 and t≥1 denote positive integers, contains at least one prime from each coprime congruence class. We prove this conjecture first ... [more ▼]

We conjecture that any interval of the form [q^t ,q^(t+1) ], where q≥ 2 and t≥1 denote positive integers, contains at least one prime from each coprime congruence class. We prove this conjecture first unconditionally for all 2≤q≤45000 and all t≥1 and second under ERH for almost all q≥2 and all t≥2. Furthermore, we outline heuristic arguments for the validity of the conjecture beyond the proven bounds and we compare it with related long-standing conjectures. Finally, we discuss some of its consequences. [less ▲]

Modelling challenges & simulation results comparison study for inactive elements activation approach in numerical simulation of Selective Laser Melting Additive Manufacturing process

E-print/Working paper (n.d.)

Weakening the tight coupling between geometry and simulation in isogeometric analysis: from sub- and super- geometric analysis to Geometry Independent Field approximaTion (GIFT)

E-print/Working paper (n.d.)

This paper presents an approach to generalize the concept of isogeometric analysis (IGA) by allowing different spaces for parameterization of the computational domain and for approximation of the solution ... [more ▼]

This paper presents an approach to generalize the concept of isogeometric analysis (IGA) by allowing different spaces for parameterization of the computational domain and for approximation of the solution field. The method inherits the main advantage of isogeometric analysis, i.e. preserves the original, exact CAD geometry (for example, given by NURBS), but allows pairing it with an approximation space which is more suitable/flexible for analysis, for example, T-splines, LR-splines, (truncated) hierarchical B-splines, and PHT-splines. This generalization offers the advantage of adaptive local refinement without the need to re-parameterize the domain, and therefore without weakening the link with the CAD model. We demonstrate the use of the method with different choices of the geometry and field splines, and show that, despite the failure of the standard patch test, the optimum convergence rate is achieved for non-nested spaces. [less ▲]

Not participating in education, employment or training (NEET): Hope to mitigate new social risks in the UK?

E-print/Working paper (n.d.)

Young people not participating in education, employment or training (NEET) are a key policy concern in Europe. We examine whether hope, as a form of life course agency, plays a protective role against the ... [more ▼]

Young people not participating in education, employment or training (NEET) are a key policy concern in Europe. We examine whether hope, as a form of life course agency, plays a protective role against the risk of being NEET in the context of the British welfare state. Hope is conceptualised as multidimensional: being a temporally embedded, agentic mentality comprised of one’s sense of adaptive decision-making in the present and pathways thinking towards the future. Longitudinal estimations based on the latest Understanding Society microdata (2009-2018) indicate a direct association between higher-hope modes, on average, and a lower likelihood of being NEET. Further, our study assesses whether hopeful agency is moderated by the experience of parental worklessness. Findings indicate that while hope is not more important for those who experienced disadvantages in upbringing, hopeful agency is shown to be equally important in the face of past and present NEET risks. For the UK, building young peoples’ adaptive, agentic mentality towards their future in education or employment over the long-term, may prove one cost-effective policy approach. [less ▲]

Prime divisors of the l-Genocchi numbers and the ubiquity of Ramanujan-style congruences of level l

E-print/Working paper (n.d.)

Let \ell be any fixed prime number. We define the \ell-Genocchi numbers by G_n:=\ell(1-\ell^n)B_n, with B_n the n-th Bernoulli number. They are integers. We introduce and study a variant of Kummer's ... [more ▼]

Let \ell be any fixed prime number. We define the \ell-Genocchi numbers by G_n:=\ell(1-\ell^n)B_n, with B_n the n-th Bernoulli number. They are integers. We introduce and study a variant of Kummer's notion of regularity of primes. We say that an odd prime p is \ell-Genocchi irregular if it divides at least one of the \ell-Genocchi numbers G_2,G_4,..., G_{p-3}, and \ell-regular otherwise. With the help of techniques used in the study of Artin's primitive root conjecture, we give asymptotic estimates for the number of \ell-Genocchi irregular primes in a prescribed arithmetic progression in case \ell is odd. The case \ell=2 was already dealt with by Hu, Kim, Moree and Sha (2019). Using similar methods we study the prime factors of (1-\ell^n)B_{2n}/2n and (1+\ell^n)B_{2n}/2n. This allows us to estimate the number of primes p\leq x for which there exist modulo p Ramanujan-style congruences between the Fourier coefficients of an Eisenstein series and some cusp form of prime level \ell. [less ▲]

Boy or Girl?

E-print/Working paper (n.d.)

The Hardest Logic Puzzle Ever

E-print/Working paper (n.d.)

Kummer theory for finite fields and p-adic fields

E-print/Working paper (n.d.)

Let K be a finite field or a finite extension of Qp for some prime number p. If G is a finitely generated subgroup of K*, then we can consider the degree of the cyclotomic-Kummer extension K(\zeta_N ... [more ▼]

Let K be a finite field or a finite extension of Qp for some prime number p. If G is a finitely generated subgroup of K*, then we can consider the degree of the cyclotomic-Kummer extension K(\zeta_N, \sqrt[n]{G})/K, where n divides N. If K is a finite field, then we give a closed formula for the degree, while if K is a p-adic field, then we describe a strategy to compute the degree. [less ▲]

SOS Sudoku

E-print/Working paper (n.d.)

Correspondences between WZNW models and CFTs with W-algebra symmetry

E-print/Working paper (n.d.)

TikZ is more than meets the eyes

E-print/Working paper (n.d.)

Three-dimensional arithmetic billiards

E-print/Working paper (n.d.)

A Simple Inner-Product Functional Encryption Scheme from the Inverse-DDH Assumption

E-print/Working paper (n.d.)

Kummer extensions of number fields (the case of rank 2)

E-print/Working paper (n.d.)

Divisibility conditions on the order of the reductions of algebraic numbers

E-print/Working paper (n.d.)

Let K be a number field, and let G be a finitely generated subgroup of K*. Without relying on (GRH) we prove an asymptotic formula for the number of primes \p of K such that the order of (G mod \p) is ... [more ▼]

Let K be a number field, and let G be a finitely generated subgroup of K*. Without relying on (GRH) we prove an asymptotic formula for the number of primes \p of K such that the order of (G mod \p) is divisible by a fixed integer. We also provide a rational expression for the natural density of this set. Furthermore, we study the primes \p for which the order is k-free, and those for which the order has a prescribed \ell-adic valuation for finitely many primes \ell. An additional condition on the Frobenius conjugacy class of \p may be considered. In order to establish these results, we prove an unconditional version of the Chebotarev density theorem for Kummer extensions of number fields. [less ▲]

Calabi-Yau structures on (quasi)-bisymplectic algebras

E-print/Working paper (n.d.)

Mathematical hourglasses, just in time

E-print/Working paper (n.d.)

The least common multiple of several numbers in terms of greatest common divisors

E-print/Working paper (n.d.)

A local-global principle for polyquadratic twists of abelian surfaces

E-print/Working paper (n.d.)

A new one point quadrature rule over arbitrary star convex polygon/polyhedron

E-print/Working paper (n.d.)

The Linear Smoothing (LS) scheme \cite{francisa.ortiz-bernardin2017} ameliorates linear and quadratic approximations over convex polytopes by employing a three-point integration scheme. In this work, we ... [more ▼]

The Linear Smoothing (LS) scheme \cite{francisa.ortiz-bernardin2017} ameliorates linear and quadratic approximations over convex polytopes by employing a three-point integration scheme. In this work, we propose a linearly consistent one point integration scheme which possesses the properties of the LS scheme with three integration points but requires one third of the integration computational time. The essence of the proposed technique is to approximate the strain by the smoothed nodal derivatives that are determined by the discrete form of the divergence theorem. This is done by the Taylor's expansion of the weak form which facilitates the evaluation of the smoothed nodal derivatives acting as stabilization terms. The smoothed nodal derivatives are evaluated only at the centroid of each integration cell. These integration cells are the simplex subcells (triangle/tetrahedron in two and three dimensions) obtained by subdividing the polytope. The salient feature of the proposed technique is that it requires only $n$ integrations for an $n-$ sided polytope as opposed to $3n$ in~\cite{francisa.ortiz-bernardin2017} and $13n$ integration points in the conventional approach. The convergence properties, the accuracy, and the efficacy of the LS with one point integration scheme are discussed by solving few benchmark problems in elastostatics. [less ▲]