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See detailSpatial PAPR Reduction in Symbol-level Precoding for the Multi-beam Satellite Downlink
Spano, Danilo UL; Alodeh, Maha UL; Chatzinotas, Symeon UL et al

in IEEE SPAWC 2017 (2017, July)

In this work, a novel symbol-level precoding scheme is proposed, for managing the multi-user interference in the forward downlink channel of a multi-beam satellite system. Besides exploiting the ... [more ▼]

In this work, a novel symbol-level precoding scheme is proposed, for managing the multi-user interference in the forward downlink channel of a multi-beam satellite system. Besides exploiting the constructive interference effect, the proposed scheme aims at improving the robustness of the transmitted signals to the non-linear distortions of practical satellite systems. This is done by reducing the imbalances between the instantaneous power transmitted by the multiple antennas, which are detrimental in non-linear systems. More specifically, this work proposes a symbol-level precoding scheme performing the minimization of the spatial peak-to-average power ratio, under Quality-of-Service constraints. An iterative algorithm is proposed to solve the related optimization problem. Numerical results are presented to assess the performance of the proposed scheme, which outperforms the state of the art symbol-level precoding techniques in terms of spatial peak-to-average power ratio across the transmitting antennas. [less ▲]

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See detailPower Allocation for In-Band Full-Duplex Self-Backhauling
Lagunas, Eva UL; Lei, Lei UL; Maleki, Sina UL et al

in International Conference on Telecommunications and Signal Processing (TSP), Barcelona, Spain, July 2017 (2017, July)

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See detailProfiles of students on account of complex problem solving strategies
Gnaldi, M.; Bacci, S.; Greiff, Samuel UL et al

Scientific Conference (2017, July)

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See detailTo use or not to use? Investigating the validity argument for the use of short scales in research settings
Kemper, Christoph UL; Becker, N.; Baudson, T. G. et al

Scientific Conference (2017, July)

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See detailEnergy-Efficient Design for Edge-caching Wireless Networks: When is Coded-caching beneficial?
Vu, Thang Xuan UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in Abstract book of 2017 IEEE 18th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC) (2017, July)

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See detailThe interference of pain with task performance: Increasing ecological validity in research
van Ryckeghem, Dimitri UL

in Scandinavian Journal of Pain (2017), 16

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See detailProceedings of International Conference on Software and Systems Process (ICSSP)
Kuhrmann, Marco; Diebold, Philipp; Münch, Jürgen et al

in Hybrid software and system development in practice: Waterfall, scrum, and beyond (2017, July)

Software and system development faces numerous challenges of rapidly changing markets. To address such challenges, companies and projects design and adopt specific development approaches by combining well ... [more ▼]

Software and system development faces numerous challenges of rapidly changing markets. To address such challenges, companies and projects design and adopt specific development approaches by combining well-structured comprehensive methods and flexible agile practices. Yet, the number of methods and practices is large, and available studies argue that the actual process composition is carried out in a fairly ad-hoc manner. The present paper reports on a survey on hybrid software development approaches. We study which approaches are used in practice, how different approaches are combined, and what contextual factors influence the use and combination of hybrid software development approaches. Our results from 69 study participants show a variety of development approaches used and combined in practice. We show that most combinations follow a pattern in which a traditional process model serves as framework in which several fine-grained (agile) practices are plugged in. We further show that hybrid software development approaches are independent from the company size and external triggers. We conclude that such approaches are the results of a natural process evolution, which is mainly driven by experience, learning, and pragmatism. [less ▲]

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See detailThe effect of training morphosyntactic markers in German and in French on multilingual fifth-graders' spelling.
Bilici, Natalia UL; Ugen, Sonja UL; Weth, Constanze UL

Scientific Conference (2017, June 26)

Many studies focussing on spelling in French and German languages show that, even by the end of the primary school, pupils have difficulties to encode morphosyntactic information in their writing ... [more ▼]

Many studies focussing on spelling in French and German languages show that, even by the end of the primary school, pupils have difficulties to encode morphosyntactic information in their writing. Particularly problematic are, for instance, capitalisation of nouns in German (Betzel 2014) or plural markers in French (Fayol et al. 2006), because they are inaudible and require knowledge that goes beyond simple phoneme-grapheme correspondences. Our paper presents how multilingual learners deal with silent morphosyntactic markers in French and German and shows the effects of an intervention training on children's spelling performance. In total our study included 228 multilingual fifth graders (mean age 11 years) with four years instruction in German and two years instruction in French. They were assigned to an intervention (n=137) and to a control group (n=91) based on the results of a spelling test in French and German. This was done by creating performance groups that were, in a second step, attributed to one of the experimental groups taking their performance into account (quasi-randomised procedure). The French test consisted of three word categories of different difficulty (nouns, verbs, adjectives). For adjectives only, position (pre- vs. post-nominal) was also manipulated. The German test focussed on three lexical-semantic characteristics (concrete nouns, abstract nouns, nominalizations) and four syntactical positions (determinant+noun, determinant+adjective+noun, adjective+noun, noun) frequent words and pseudo-words. Additionally, word frequency was manipulated within each language (frequent words vs. pseudowords). These difficulty levels have been based on the literature published on monolingual learners (French: Totereau et al. (2014), German: Funke (2005); Guenther (2007); Betzel (2014)). The children participated in 12 intervention sessions of 20 minutes each (six in German and six in French, the order was counterbalanced). Children of the intervention group were trained to improve their morphosyntactic awareness and thus spelling performance of French plurals and German capitalization. The control group received the same amount of language input than the intervention group, but they were trained on another aspect of language i.e. listening comprehension. Results from the pre-test show that multilingual children acquiring German and French show similar difficulty patterns as German or French monolinguals. The post-test shows that the intervention group improved significantly in both their German and French spelling in comparison to the control group in all word and pseudo-word categories and positions. The intervention group's performance increased especially on pseudo-words, indicating that the training had an effect on children's spelling according to syntactic regularities. The study results are specifically important to better understand the learning processes of morphosyntactic spelling in primary school. The implications on the teaching methods will be discussed. [less ▲]

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See detailASIMUT project: Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques
Bouvry, Pascal UL; Chaumette, Serge; Danoy, Grégoire UL et al

in DroNet'17 Proceedings of the 3rd Workshop on Micro Aerial Vehicle Networks, Systems, and Applications (2017, June 23)

This document summarizes the activities and results of the ASIMUT project (Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques) carried out by the consortium ... [more ▼]

This document summarizes the activities and results of the ASIMUT project (Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques) carried out by the consortium composed of Thales, Fraunhofer IOSB, Fly-n-Sense, University of Bordeaux and University of Luxembourg. Funded by the European Defence Agency (EDA), the objectives of the ASIMUT project are to design, implement and validate algorithms that will allow the efficient usage of autonomous swarms of Unmanned Aerial Vehicles (UAVs) for surveillance missions. [less ▲]

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See detailZur Zufriedenheit von Mitgliedern des Verwaltungsrats und der Geschäftsleitung Schweizer Aktiengesellschaften mit dem "umfassenden Bericht" der Revisionsstelle : Ergebnisse einer explorativen Studie
Muessig, Anke UL

in Funk, Wilfried (Ed.) Internationale Rechnungslegung und Internationales Controlling : Herausforderungen - Handlungsfelder - Erfolgspotenziale (2017)

In der Schweiz sind zum 1. Januar 2008 die geänderten Artikel des Obligationenrechts (OR) zur Abschlussprüfung (sog. ordentliche Revision) in Kraft getreten. Ein Ziel der Reform ist es gewesen, die ... [more ▼]

In der Schweiz sind zum 1. Januar 2008 die geänderten Artikel des Obligationenrechts (OR) zur Abschlussprüfung (sog. ordentliche Revision) in Kraft getreten. Ein Ziel der Reform ist es gewesen, die Qualität der ordentlichen Revision zu erhöhen. Ansatzpunkte waren insbesondere die Verbesserung der Kommunikation der Revisionsstelle mit dem Verwaltungsrat (VR) durch die Einführung des sog. umfassenden Berichts und die Erweiterung des Prüfungsumfangs um die Prüfung der Existenz des Internen Kontrollsystems (IKS). Der vorliegende Beitrag adressiert die Unsicherheiten der Revisionsstellen beim umfassenden Bericht. Ziel ist es, erstmalig und in einer breitangelegten Befragung von VR- und GL-Mitgliedern ihre Zufriedenheit mit dem umfassenden Bericht zu erheben. Die Ergebnisse der explorativen Studie sollen den Wirtschaftsprüfungsgesellschaften Verbesserungspotenziale hinsichtlich ihrer Berichterstattung aufzeigen und Ansatzpunkte für eine „passgenaue” Berichterstattung liefern. [less ▲]

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See detailWho Trade at Better Prices?
Wolff, Christian UL; Ekkayokkaya, Manapol

E-print/Working paper (2017)

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See detailLocalisation résidentielle de la population étrangère selon la nationalité et la structure urbaine au Luxembourg
Pigeron-Piroth, Isabelle UL; Heinz, Andreas UL; Caruso, Geoffrey UL

Presentation (2017, June 19)

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

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

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See detailLocalisation résidentielle de la population étrangère selon la nationalité et la structure urbaine au Luxembourg
Pigeron-Piroth, Isabelle UL; Heinz, Andreas UL; Caruso, Geoffrey UL

E-print/Working paper (2017)

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

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

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See detailRecent results on conservative and symmetric n-ary semigroups
Kiss, Gergely UL; Devillet, Jimmy UL; Marichal, Jean-Luc UL

Scientific Conference (2017, June 16)

See attached file

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See detailOn conservative and associative operations on finite chains
Devillet, Jimmy UL; Couceiro, Miguel; Marichal, Jean-Luc UL

Scientific Conference (2017, June 16)

See attached file

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See detailWhat industry wants from academia in software testing? Hearing practitioners’ opinions
Garousi, Vahid UL; Felderer, Michael; Kuhrmann, Marco et al

in Proceedings of International Conference on Evaluation and Assessment in Software Engineering (EASE) (2017, June 15)

The level of industry-academia collaboration (IAC) in software engineering in general and in software testing in particular is quite low. Many researchers and practitioners are not collaborating with the ... [more ▼]

The level of industry-academia collaboration (IAC) in software engineering in general and in software testing in particular is quite low. Many researchers and practitioners are not collaborating with the “other side” to solve industrial problems. To shed light on the above issue and to characterize precisely what industry wants from academia in software testing, we solicited practitioners’ opinions on their challenges in different testing activities and also the particularly relevant topics that they want the research community to work on. This short paper aims to draw the community’s attention to the important issue of strengthening IAC with the hope of more IAC in software testing in the areas of most importance to the industry. [less ▲]

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See detailChoosing the Right Test Automation Tool: a Grey Literature Review of Practitioner Sources
Raulamo-Jurvanen, Päivi; Mäntylä, Mika; Garousi, Vahid UL

in Choosing the Right Test Automation Tool: a Grey Literature Review of Practitioner Sources (2017, June 15)

Background: Choosing the right software test automation tool is not trivial, and recent industrial surveys indicate lack of right tools as the main obstacle to test automation. Aim: In this paper, we ... [more ▼]

Background: Choosing the right software test automation tool is not trivial, and recent industrial surveys indicate lack of right tools as the main obstacle to test automation. Aim: In this paper, we study how practitioners tackle the problem of choosing the right test automation tool. Method: We synthesize the “voice” of the practitioners with a grey literature review originating from 53 different companies. The industry experts behind the sources had roles such as “Software Test Automation Architect”, and “Principal Software Engineer”. Results: Common consensus about the important criteria exists but those are not applied systematically. We summarize the scattered steps from individual sources by presenting a comprehensive process for tool evaluation with 12 steps and a total of 14 different criteria for choosing the right tool. Conclusions: The practitioners tend to have general interest in and be influenced by related grey literature as about 78% of our sources had at least 20 backlinks (a reference comparable to a citation) while the variation was between 3 and 759 backlinks. There is a plethora of different software testing tools available, yet the practitioners seem to prefer and adopt the widely known and used tools. The study helps to identify the potential pitfalls of existing processes and opportunities for comprehensive tool evaluation. [less ▲]

Detailed reference viewed: 16 (3 UL)