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See detailAutomated Test Case Generation as a Many-Objective Optimisation Problem with Dynamic Selection of the Targets
Panichella, Annibale UL; Kifetew, Fitsum; Tonella, Paolo

in IEEE Transactions on Software Engineering (in press)

The test case generation is intrinsically a multi-objective problem, since the goal is covering multiple test targets (e.g., branches). Existing search-based approaches either consider one target at a ... [more ▼]

The test case generation is intrinsically a multi-objective problem, since the goal is covering multiple test targets (e.g., branches). Existing search-based approaches either consider one target at a time or aggregate all targets into a single fitness function (whole-suite approach). Multi and many-objective optimisation algorithms (MOAs) have never been applied to this problem, because existing algorithms do not scale to the number of coverage objectives that are typically found in real-world software. In addition, the final goal for MOAs is to find alternative trade-off solutions in the objective space, while in test generation the interesting solutions are only those test cases covering one or more uncovered targets. In this paper, we present DynaMOSA (Dynamic Many-Objective Sorting Algorithm), a novel many-objective solver specifically designed to address the test case generation problem in the context of coverage testing. DynaMOSA extends our previous many-objective technique MOSA (Many-Objective Sorting Algorithm) with dynamic selection of the coverage targets based on the control dependency hierarchy. Such extension makes the approach more effective and efficient in case of limited search budget. We carried out an empirical study on 346 Java classes using three coverage criteria (i.e., statement, branch, and strong mutation coverage) to assess the performance of DynaMOSA with respect to the whole-suite approach (WS), its archive-based variant (WSA) and MOSA. The results show that DynaMOSA outperforms WSA in 28% of the classes for branch coverage (+8% more coverage on average) and in 27% of the classes for mutation coverage (+11% more killed mutants on average). It outperforms WS in 51% of the classes for statement coverage, leading to +11% more coverage on average. Moreover, DynaMOSA outperforms its predecessor MOSA for all the three coverage criteria in 19% of the classes with +8% more code coverage on average. [less ▲]

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See detailAutobiografia ed emigrazione. Ricordare, raccontare, costruire
Cicotti, Claudio UL

Book published by Lang (in press)

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See detailIslamic banking development and access to credit
Leon, Florian UL; Weill, Laurent

in Pacific-Basin Finance Journal (in press)

The recent expansion of Islamic banks raises questions on its economic implications. The aim of this paper is to investigate the impact of Islamic banking development on access to credit. We combine data ... [more ▼]

The recent expansion of Islamic banks raises questions on its economic implications. The aim of this paper is to investigate the impact of Islamic banking development on access to credit. We combine data from a unique hand-collected database that covers Islamic banks with firm-level data covering developing and emerging countries over the period of 2006 to 2009. We find that Islamic banking development has overall no impact on credit constraints, while banking development and conventional banking development alleviate obstacles to financing. However Islamic banking development exerts a positive impact on access to credit when conventional banking development is low. Hence we support the view that Islamic banking does not overall alleviate obstacles to financing, but it can act as substitute to conventional banking. [less ▲]

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See detailCharacterizations of idempotent discrete uninorms
Couceiro, Miguel; Devillet, Jimmy UL; Marichal, Jean-Luc UL

in Fuzzy Sets & Systems (in press)

In this paper we provide an axiomatic characterization of the idempotent discrete uninorms by means of three conditions only: conservativeness, symmetry, and nondecreasing monotonicity. We also provide an ... [more ▼]

In this paper we provide an axiomatic characterization of the idempotent discrete uninorms by means of three conditions only: conservativeness, symmetry, and nondecreasing monotonicity. We also provide an alternative characterization involving the bisymmetry property. Finally, we provide a graphical characterization of these operations in terms of their contour plots, and we mention a few open questions for further research. [less ▲]

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See detailLe Brexit et les accords mixtes de l'Union européenne
Neframi, Eleftheria UL

in Annuaire Français de Droit International (in press)

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See detailDynamic interplay of language policy, beliefs and pedagogy in a nursery class in Luxembourg
Kirsch, Claudine UL

in Language and Education (in press)

This presentation focuses on the relationship between the language policy, language ideologies and language practices in a nursery class in trilingual Luxembourg. Individual multilingualism is an ... [more ▼]

This presentation focuses on the relationship between the language policy, language ideologies and language practices in a nursery class in trilingual Luxembourg. Individual multilingualism is an educational goal in Luxembourg, a small country in central Europe, and, thus, children learn Luxembourgish from the compulsory nursery school, become literate in German in Year 1 and learn oral and written French from Year 2 and Year 3, respectively. Currently, 62.4% of the children do not speak Luxembourgish on school entry (MENJE 2016). Many speak Portuguese, French or a language of the Balkans. As a result, educational policies focus on the teaching of Luxembourgish from preschool, sometimes at the expense of other languages. Gretsch and Kirsch (2015) developed the app iTEO in order to promote innovative teaching methods that capitalize on the children’s diverse language resources and that promote a dynamic view of bilingualism. This ipad app, which allows for the recording and editing of oral speech, was designed with social-constructivist theories and Bakhtin’s theory of dialogism in mind. This case-study presents the ways in which a preschool teacher’s ideological beliefs influence a child’s language use over a period of two years leading to the child’s understanding of the legitimacy of translanguaging. The focus lies on the interplay between the educational policy focusing on the teaching of Luxembourgish, the teacher’s language ideologies rooted in her multilingual identity and in societal multilingualism, and the child’s experiences of separating languages at home (Kirsch, 2014). The data stem from a qualitative, longitudinal study using a multi-method approach. The study shows that dialogue between teachers, parents, children, policy-makers and researchers can contribute to shifting ideologies and to opening up dynamic languaging spaces. [less ▲]

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See detailPivotal decomposition schemes inducing clones of operations
Couceiro, Miguel; Teheux, Bruno UL

in Contributions to Algebra and Geometry (in press)

We study pivotal decomposition schemes and investigate classes of pivotally decomposable operations. We provide sufficient conditions on pivotal operations that guarantee that the corresponding classes of ... [more ▼]

We study pivotal decomposition schemes and investigate classes of pivotally decomposable operations. We provide sufficient conditions on pivotal operations that guarantee that the corresponding classes of pivotally decomposable operations are clones, and show that under certain assumptions these conditions are also necessary. In the latter case, the pivotal operation together with the constant operations generate the corresponding clone. [less ▲]

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See detailThe Scent of a Smell: An Extensive Comparison between Textual and Structural Smells
Palomba, Fabio; Panichella, Annibale UL; Zaidman, Andy et al

in IEEE Transactions on Software Engineering (in press)

Code smells are symptoms of poor design or implementation choices that have a negative effect on several aspects of software maintenance and evolution, such as program comprehension or change- and fault ... [more ▼]

Code smells are symptoms of poor design or implementation choices that have a negative effect on several aspects of software maintenance and evolution, such as program comprehension or change- and fault-proneness. This is why researchers have spent a lot of effort on devising methods that help developers to automatically detect them in source code. Almost all the techniques presented in literature are based on the analysis of structural properties extracted from source code, although alternative sources of information (e.g., textual analysis) for code smell detection have also been recently investigated. Nevertheless, some studies have indicated that code smells detected by existing tools based on the analysis of structural properties are generally ignored (and thus not refactored) by the developers. In this paper, we aim at understanding whether code smells detected using textual analysis are perceived and refactored by developers in the same or different way than code smells detected through structural analysis. To this aim, we set up two different experiments. We have first carried out a software repository mining study to analyze how developers act on textually or structurally detected code smells. Subsequently, we have conducted a user study with industrial developers and quality experts in order to qualitatively analyze how they perceive code smells identified using the two different sources of information. Results indicate that textually detected code smells are easier to identify and for this reason they are considered easier to refactor with respect to code smells detected using structural properties. On the other hand, the latter are often perceived as more severe, but more difficult to exactly identify and remove. [less ▲]

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See detailOn the performance of an overlapping-domain parallelization strategy for Eulerian-Lagrangian Multiphysics software
Pozzetti, Gabriele UL; Besseron, Xavier UL; Rousset, Alban UL et al

in AIP Conference Proceedings ICNAAM 2017 (in press)

In this work, a strategy for the parallelization of a two-way CFD-DEM coupling is investigated. It consists on adopting balanced overlapping partitions for the CFD and the DEM domains, that aims to reduce ... [more ▼]

In this work, a strategy for the parallelization of a two-way CFD-DEM coupling is investigated. It consists on adopting balanced overlapping partitions for the CFD and the DEM domains, that aims to reduce the memory consumption and inter-process communication between CFD and DEM. Two benchmarks are proposed to assess the consistency and scalability of this approach, coupled execution on 252 cores shows that less than 1\% of time is used to perform inter-physics data exchange. [less ▲]

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See detailKommunale Selbstinszenierung im vorstädtischen Raum. Ein neuer Blick auf Leprosorien des Spätmittelalters und der frühen Neuzeit
Uhrmacher, Martin UL

in Hesse, Christian; Schulte, Daniela; Stercken, Martina (Eds.) Kommunale Selbstinszenierung (in press)

Abstract zur Tagung „Kommunale Selbstinszenierung“ der Internationalen Kommission für Stadtgeschichte, des Schweizerischen Arbeitskreises für Stadtgeschichte und des NCCR 'Mediality. Historical ... [more ▼]

Abstract zur Tagung „Kommunale Selbstinszenierung“ der Internationalen Kommission für Stadtgeschichte, des Schweizerischen Arbeitskreises für Stadtgeschichte und des NCCR 'Mediality. Historical Perspectives' Universität Zürich, 3./4./5. September 2015 Martin Uhrmacher (Universität Luxemburg) „Leprosorien als kommunale Repräsentationsbauten im vorstädtischen Raum. Ein neuer Blick auf eine bisher wenig beachtete städtische Baugattung“ Die vor den Mauern mittelalterlicher und frühneuzeitlicher Städte gelegenen Leprosorien werden heute zumeist noch immer als abgelegene und verborgene Orte der Exklusion angesehen, durch Zäune und Mauern von der Außenwelt getrennt. Dementsprechend wird auch der Baugattung „Leprosorium“ nur wenig architektonischer Wert zugebilligt, wie bspw. im Ausstellungskatalog „Aussatz – Lepra – Hansen-Krankheit: Demnach hatten sie „keinerlei repräsentative Bedeutung, im Gegenteil: eher unauffällig sollten sie sein, verborgen vor dem Blick der Stadtbewohner und Reisenden“. Im 2005 von Monika Escher und Frank G. Hirschmann publizierten Syntheseband „Die urbanen Zentren des hohen und späten Mittelalters“ zur Geschichte mittelalterlicher Städte zwischen Rhein und Maas werden Leprosorien zudem als „nicht wertungsrelevantes“ Urbanitäts- und Zentralitätskriterium“ bezeichnet; begründet mit der angeblichen „Tatsache, daß in der Regel der topographische Bezug zur Stadt gering war“. In der jüngeren Forschung hat sich diese Einschätzung nun grundlegend gewandelt. Leprosorien gelten aufgrund ihrer besonders prominent und exponiert ausgewählten Standorte an Kreuzungen, Brücken und Hauptausfallstraßen als präsente und das städtische Umland prägende kommunale Einrichtungen, die ein fester Bestandteil der städtischen Lebenswelt waren. Sie dienten nicht dazu, ihre Bewohner zu verstecken, sondern waren vielmehr mit Stiftungen und Spenden versehene städtische Einrichtungen, die vom Rat und den Bürgern auch als Prestigeobjekte betrachtet wurden. Anhand ausgewählter Beispiele wird aufgezeigt, wie Leprosorien als Repräsentationsobjekte der Stadtgemeinden auch dem bürgerlichen Selbstverständnis Ausdruck verliehen. [less ▲]

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See detailNeue Staaten – neue Grenzen. Die Rhein-Maas-Mosel-Region zwischen den Grenzbereinigungen des Ancien Régime und der Neuordnung durch den Wiener Kongress (1779 – 1816)
Uhrmacher, Martin UL

in Fickers, Andreas; Franz, Norbert; Laux, Stephan (Eds.) et al Repression, Reform und Neuordnung im Zeitalter der Revolutionen: Die Folgen des Wiener Kongresses für Westeuropa. Tagung und Workshop zum 200. Jahrestag des Abschlusses des Wiener Kongresses (in press)

Abstract Konferenz 200 Jahre Wiener Kongress Martin Uhrmacher Neue Staaten – neue Grenzen. Die Großregion zwischen den Grenzbereinigungen des Ancien Régime und der Neuordnung durch den Wiener Kongress ... [more ▼]

Abstract Konferenz 200 Jahre Wiener Kongress Martin Uhrmacher Neue Staaten – neue Grenzen. Die Großregion zwischen den Grenzbereinigungen des Ancien Régime und der Neuordnung durch den Wiener Kongress (1779 – 1816). Der Vortrag untersucht die Veränderung von Grenzen und Ihre Entwicklung von sich teils überlagernden und durch Enklaven und Gemeinsherrschaften durchsetzten historisch gewachsenen Grenzsäumen hin zu begradigten, fest definierten und teils naturräumlichen Scheidelinien folgenden Staatsgrenzen. In der heutigen Großregion vollzog sich dieser fundamentale Wandel in nur drei Jahrzehnten: Er gliederte die Region vollkommen neu. Zunächst waren es 1779 mit dem Brüsseler Vertrag nach jahrzehntelangen Verhandlungen endlich zu einem Ausgleich zwischen Österreich und Frankreich gekommen, der die Grenzstreitigkeiten beseitigte und neue, begradigte Grenzen exakt festlegte. Ein ähnlicher Vertrag wurde auch zwischen Österreich und Kurtrier abgeschlossen. Doch die als endgültig geplanten Regelungen bestanden nur wenige Jahre: Infolge der französischen Revolution annektierte die französische Republik am 1. Oktober 1795 die österreichischen Niederlande mit dem Herzogtum Luxemburg und kurz darauf auch Kurtrier und die anderen linksrheinischen Territorien. Alle Staaten wurden aufgelöst und gehörten nun zum französischen Staatsgebiet; Teile der alten Grenzen bestanden als Départementsgrenzen weiter. Nach der Absetzung Napoleons beschloss der Wiener Kongress 1815 eine Neuordnung Europas. Doch im Maas-Moselraum blieben mit Ausnahme Frankreichs alle Territorien und Landesherrschaften, die hier seit dem Früh- und Hochmittelalter bestanden hatten verschwunden. Sie wurden ersetzt durch das neu gegründete Großherzogtum Luxemburg und das ebenfalls neu gegründete Königreich der Vereinigten Niederlande sowie durch die preußische Rheinprovinz, die den gesamten östlichen Teil umfasste. Bei der territorialen Neugliederung griff man in Teilen auf die bis 1795 bestehenden Grenzen des alten Herzogtums zurück. In der Schlussakte des Wiener Kongresses behandeln die Artikel 66 bis 69 das Großherzogtum Luxemburg. Hier werden die Grenzen des neuen Staates allerdings nur grob umrissen; detaillierte Regelungen blieben späteren Verträgen vorbehalten. Unstrittig war die Süd- und Westgrenze mit Frankreich; sie entsprach der 1769/79 festgesetzten und bis 1795 gültigen Linie mit Ausnahme des ehemaligen Herzogtums Bouillon als Zugewinn. Vollkommen neu festgelegt wurde jedoch die Ostgrenze: Mit der Schlussakte des Wiener Kongresses waren alle hier an Luxemburg angrenzenden Gebiete an das Königreich Preußen gefallen. In den Verträgen von Aachen (26. Juni 1816) und Kleve (7. Oktober 1816) einigten sich die niederländische und die preußische Seite darauf, dass die Flussläufe von Mosel, Sauer und Our zukünftig die gemeinsame Grenze bildeten. Hier offenbart sich ein grundlegender Wandel im Verständnis und der Genese von Grenzen: Bisher waren territoriale Veränderungen auf Grundlage historisch gewachsener Herrschaftsstrukturen vorgenommen worden. So konnten kleinere Herrschaften aber auch größere Gebietskonglomerate zwar durch Tausch, Verkauf, Abtretung oder - wie durch Frankreich praktiziert - als „Reunionen“ die territoriale Zugehörigkeit wechseln. Dabei wurden jedoch die historisch gewachsenen Grenzen beachtet, sogar noch bei der Einrichtung der französischen Départements 1795. Mit der Wahl des Flußverlaufs von Sauer und Our als Grenze zwischen Luxemburg und Preußen wurde dieses Prinzip durchbrochen und ein naturräumliches Gliederungselement als neu geschaffene Grenze gewählt. [less ▲]

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See detailTagungsbericht: 71. International Fiscal Association Kongress 2017
Sinnig, Julia UL

in Internationale Steuer-Rundschau : Zeitschrift für Internationales Steuerrecht (in press)

The 71st International Fiscal Association (IFA) Congress took place from 27 August to 1 September 2017 in Rio de Janeiro. The two main subjects of the congress were dedicated to the status quo of the base ... [more ▼]

The 71st International Fiscal Association (IFA) Congress took place from 27 August to 1 September 2017 in Rio de Janeiro. The two main subjects of the congress were dedicated to the status quo of the base erosion and profit shifting (BEPS) project and the future of transfer pricing. In addition, further seminars covered ten other topics. [less ▲]

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See detailEstablished risk factors for addiction failto discriminate between healthy gamers and gamers endorsing DSM-5 Internet gaming disorder
Deleuze, Jory; Nuyens, Filip; Rochat, Lucien et al

in Journal of Behavioral Addictions (in press)

Background and aims: The DSM-5 includes criteria for diagnosing Internet gaming disorder (IGD) that are adapted from substance abuse and widely used in research and clinical contexts, although evidence ... [more ▼]

Background and aims: The DSM-5 includes criteria for diagnosing Internet gaming disorder (IGD) that are adapted from substance abuse and widely used in research and clinical contexts, although evidence supporting their validity remains scarce. The present study compared online gamers who do or do not endorse IGD criteria regarding self-control-related abilities (impulsivity, inhibitory control, and decision making), considered the hallmarks of addictive behaviors. Method: A double approach was adopted to distinguish pathological from recreational gamers in a sample of gamers: The first is the classic DSM-5 approach (≥5 criteria required to endorse the IGD diagnosis), and the second consists in using latent class analysis (LCA) for IGD criteria to distinguish gamers’ subgroups. We computed comparisons separately for each approach. Ninety-seven volunteer gamers from the community were recruited. Self-reported questionnaires were used to measure demographic and game-related characteristics, problematic online gaming (with the Problematic Online Gaming Questionnaire), impulsivity (with the UPPS-P Impulsive Behavior Scale), and depression (with the Beck Depression Inventory-II). Experimental tasks were used to measure inhibitory control (Hybrid-Stop Task) and decision-making abilities (Game of Dice Task). Results: Thirty-two participants met IGD criteria (33% of the sample), whereas LCA identified two groups of gamers (pathological [35%] and recreational). Comparisons that used both approaches (DSM-5 and LCA) failed to identify significant differences regarding all constructs except for variables related to actual or problematic gaming behaviors. Discussion: The validity of IGD criteria is questioned, mostly with respect to their relevance in distinguishing high engagement from pathological involvement in video games. [less ▲]

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See detailBandes dessinées im Fremdsprachenunterricht Französisch - Annäherung an eine empirisch fundierte Teilbereichsdidaktik
Morys, Nancy UL

Book published by Peter Lang Verlag - Kolloquium Fremdsprachenunterricht (in press)

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See detailAre octroyed constitutions of the 19th century to be considered as 'imposed constitutions'?
Gerkrath, Jörg UL

in Contiades, Xenophon (Ed.) ‘Imposed Constitutions: Aspects of Imposed Constitutionalism’ (in press)

The paper considers ‘octroyed’, ‘conceded’ or ‘granted’ constitutions of 19th century Europe whose common roots are to be found in the French ‘Charte constitutionnelle’ of 1814. These Charters stem from a ... [more ▼]

The paper considers ‘octroyed’, ‘conceded’ or ‘granted’ constitutions of 19th century Europe whose common roots are to be found in the French ‘Charte constitutionnelle’ of 1814. These Charters stem from a paternalistic process of domestic constitution-making engaged unilaterally by a monarch possessing the de facto constituent power and exercising it without the direct involvement of a body representing the people. Such octroyed constitutions, which are of course to be opposed to democratically established ones, show nevertheless a number of specific characteristics which distinguish them also from ‘imposed constitutions’ in the usual sense. The expression ‘constitutional octroy’ should not be used as a synonym for any process leading to an ‘imposed Constitution’. The contribution aims to develop and to validate or invalidate the value of a series of distinctive criteria and possible elements of a definition of ‘octroyed’ or ‘granted’ constitutions in order to underline their specificity. [less ▲]

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See detailAttention bias modification training for adolescents with chronic pain: A randomized placebo-controlled trial
Heathcote, Lauren C; Jacobs, Conrad; van Ryckeghem, Dimitri UL et al

in Pain (in press)

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See detailExploring gambling craving through the elaborated intrusion theory of desire: a mixed methods approach
Cornil, Aurélien; Lopez-Fernandez, Olatz; Devos, Gaëtan et al

in International Gambling Studies (in press)

Gambling disorder is a well-established behavioural addiction, which was classified with substance-related disorders in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders ... [more ▼]

Gambling disorder is a well-established behavioural addiction, which was classified with substance-related disorders in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. Although craving was introduced as a new diagnostic criterion for substance-related disorders, it was not included for gambling disorder. This study aimed to explore the experience of gambling craving and to evaluate whether the elaborated intrusion theory of desire (EIT), a cognitive model of craving, fits gambling craving. A mixed methods study was conducted among 31 non-clinical gamblers. The qualitative part consisted of open-ended questions targeting the components of the EIT. The quantitative part consisted of a questionnaire designed to assess triggers and descriptions of gambling craving. Qualitative analysis revealed six distinct conceptual categories related to gambling craving: positive and negative affect, external cues, mental imageries, thoughts and physiological sensations. The quantitative analysis highlighted the most relevant triggers (e.g. spontaneous thoughts) and experiential characteristics (e.g. visual imagery) of gambling craving. The present study allowed the authors to support the relevance of the EIT as it applies to gambling craving by disentangling its core features. Findings from this study suggest that the use of interventions derived from the EIT may be relevant for problem gambling treatment. [less ▲]

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See detailJoint Precoding and On-Board Beamforming for Multiple gateway Multibeam Satellite Systems
Joroughi, Vahid UL

in Submitted to IEEE Journal on Selected topic in Communication (JSAC) (in press)

This paper aims to design joint precoding and onboard beamforming of a multiple gateway multibeam satellite system, either in a hybrid space-ground mode, or in a totally on-board one. In such an ... [more ▼]

This paper aims to design joint precoding and onboard beamforming of a multiple gateway multibeam satellite system, either in a hybrid space-ground mode, or in a totally on-board one. In such an architecture, with employing high throughput full frequency reuse pattern over both user and feeder links, each gateway serves a cluster of adjacent beams such that the adjacent clusters are served through a set of gateways that are located at different geographical areas. However, such a system brings in two challenges to overcome. First, the interference in both user and feeder links is the bottleneck of the whole system and applying interference mitigation techniques becomes necessary. Second, as the data demand increases, the ground and space segments should employ extensive bandwidth resources in the feeder link accordingly. This entails embedding an extra number of gateways aiming to support a fair balance between the increasing demand and the corresponding required feeder link resources. To solve these problems, this study investigates the impact of employing a joint multiple gateway architecture and on-board beamforming scheme. It is shown that by properly designing the on-board beamforming scheme, the number of gateways can be kept affordable even if the data demand increases. Moreover, Zero Forcing (ZF) precoding techniques are considered to cope with the interference in both user and feeder links which embed in the following premises: (i) each gateway constructs a part of block ZF precoding matrix, (ii) the satellite and gateways perform the precoding scheme, and (iii) a joint design of ZF precoding and on-board beamforming at the payload of the satellite so that no signal processing scheme is conceived at the gateways. The provided simulation results depict the performance gain obtained by our proposed schemes. [less ▲]

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