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See detailA Model-driven Approach to Trace Checking of Temporal Properties with Aggregations
Boufaied, Chaima UL; Bianculli, Domenico UL; Briand, Lionel UL

in Journal of Object Technology (in press), 18(2), 151-20

The verification of complex software systems often requires to check quantitative properties that rely on aggregation operators (e.g., the average response time of a service). One way to ease the ... [more ▼]

The verification of complex software systems often requires to check quantitative properties that rely on aggregation operators (e.g., the average response time of a service). One way to ease the specification of these properties is to use property specification patterns, such as the ones for “service provisioning”, previously proposed in the literature. In this paper we focus on the problem of performing offline trace checking of temporal properties containing aggregation operators. We first present TemPsy-AG, an extension of TemPsy—an existing pattern-based language for the specification of temporal properties—to support service provisioning patterns that use aggregation operators. We then extend an existing model-driven procedure for trace checking, to verify properties expressed in TemPsy-AG. The trace checking procedure relies on the efficient mapping of temporal properties written in TemPsy-AG into OCL constraints on a meta-model of execution traces. We have implemented this procedure in the TemPsy-Check-AG tool and evaluated its performance: our approach scales linearly with respect to the length of the input trace and can deal with much larger traces than a state-of-the-art tool. [less ▲]

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See detailBankruptcy protection in airline markets: Does the impact vary in international and US domestic markets?
Mantin, Benny UL; Forsyth, Peter; Bock, Sebastian et al

in Transportation Research Part A (in press)

We study the effects of Chapter 11 bankruptcy protection on competitive product pricing in both domestic and international markets using data from the airline industry. We find a decline of about 5% in ... [more ▼]

We study the effects of Chapter 11 bankruptcy protection on competitive product pricing in both domestic and international markets using data from the airline industry. We find a decline of about 5% in domestic markets and an even more significant drop in international markets. Further, in international markets the competing carriers respond by dropping their prices as well, whereas they slightly increase them domestically. By contrast, existing literature considers only domestic markets finding a more moderate fare drop of about 3% in domestic markets by the bankrupt carrier, with mixed results on the fare drop by competitors. [less ▲]

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See detailTranscriptome profiling data reveals Ubiquitin-Specific Peptidase 9 knockdown effects
Glaab, Enrico UL; Antony, Paul UL; Köglsberger, Sandra et al

in Data in Brief (in press)

Ubiquitin specific peptidase 9 (USP9) is a deubiquitinase encoded by a sex-linked gene with a Y-chromosomal form (USP9Y) and an X-chromosomal form (USP9X) that escapes X-inactivation. Since USP9 is a key ... [more ▼]

Ubiquitin specific peptidase 9 (USP9) is a deubiquitinase encoded by a sex-linked gene with a Y-chromosomal form (USP9Y) and an X-chromosomal form (USP9X) that escapes X-inactivation. Since USP9 is a key regulatory gene with sex-linked expression in the human brain, the gene may be of interest for researchers studying molecular gender differences and ubiquitin signaling in the brain. To assess the downstream effects of knocking down USP9X and USP9Y on a transcriptome-wide scale, we have conducted microarray profiling experiments using the human DU145 prostate cancer cell culture model, after confirming the robust expression of both USP9X and USP9Y in this model. By designing shRNA constructs for the specific knockdown of USP9X and the joint knockdown of USP9X and USP9Y, we have compared gene expression changes in both knockdowns to control conditions to infer potential shared and X- or Y-form specific alterations. Here, we provide details of the corresponding microarray profiling data, which has been deposited in the Gene Expression Omnibus database (GEO series accession number GSE79376). A biological interpretation of the data in the context of a potential involvement of USP9 in Alzheimer’s disease has previously been presented in Köglsberger et al. (2016). To facilitate the re-use and re-analysis of the data for other applications, e.g. the study of ubiquitin signaling and protein turnover control, and the regulation of molecular gender differences in the human brain and brain-related disorders, we provide a more in-depth discussion of the data properties, specifications and possible use cases. [less ▲]

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See detailCVH Malach – Centrum vizuální historie Konference a workshop o novém přístupu a využití video databáze Fortunoff
Bronec, Jakub UL

in Marginalia Historica (2020)

On May 18, I took part in a very interesting workshop organized by the Malach Centre for Visual History at the Faculty of Mathematics and Physics of the Charles University in Prague. This exceptional ... [more ▼]

On May 18, I took part in a very interesting workshop organized by the Malach Centre for Visual History at the Faculty of Mathematics and Physics of the Charles University in Prague. This exceptional association provides local access to the extensive digital archives of the USC Shoah Foundation - the Institute for Visual history and Education (USC), the Refugee Voices archive of the Association of Jewish Refugees and the testimony collection of the Jewish Holocaust Centre in Melbourne. Nevertheless, the workshop focused on the newly incorporated Fortunoff Video Archive (FVA) that belongs to the category of long-awaited ingestion, and the path to get a licence was more than difficult. The archive represents a new source for all scholars including me, but in this short comment, I would like to critically point out to several minor drawbacks. [less ▲]

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See detailAttirer et retenir des étudiants internationaux au Luxembourg
Petry, Ralph UL; Coda, Nicolas UL; Sommarribas, Adolfo UL et al

Article for general public (2019)

La note de synthèse présente les principaux résultats de l’étude réalisée en 2018 par le Point de contact Luxembourgeois du Réseau Européen des Migrations intitulée : « Attracting and retaining ... [more ▼]

La note de synthèse présente les principaux résultats de l’étude réalisée en 2018 par le Point de contact Luxembourgeois du Réseau Européen des Migrations intitulée : « Attracting and retaining international students in the EU ». Cette étude fournit un aperçu des politiques et pratiques en vigueur au Luxembourg afin d’attirer et de retenir des étudiants internationaux. Elle se base essentiellement sur les informations recueillies jusqu’en novembre 2018 et n’englobe donc que peu d’évolutions qui ont pu se produire après cette date. [less ▲]

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See detailAn enhanced interface model for friction fatigue problems of axially loaded piles
Kullolli, Borana; Baeßler, Matthias; Cuéllar, Pablo et al

in Proceedings of the ASME 2019 38th, International Conference on Ocean, Offshore and Arctic Engineering, Glasgow 9-14 June 2019 (2019, June 09)

The shaft bearing capacity often plays a dominant role for the overall structural behaviour of axially loaded piles in offshore deep foundations. Under cyclic loading, a narrow zone of soil at the pile ... [more ▼]

The shaft bearing capacity often plays a dominant role for the overall structural behaviour of axially loaded piles in offshore deep foundations. Under cyclic loading, a narrow zone of soil at the pile-soil interface is subject to cyclic shearing solicitations. Thereby, the soil may densify and lead to a decrease of confining stress around the pile due to micro-phenomena such as particle crushing, migration and rearrangement. This reduction of radial stress has a direct impact on the shaft capacity, potentially leading in extreme cases to pile failure. An adequate interface model is needed in order to model this behaviour numerically. Different authors have proposed models that take typical interface phenomena in account such as densification, grain breakage, normal pressure effect and roughness. However, as the models become more complex, a great number of material parameters need to be defined and calibrated. This paper proposes the adoption and transformation of an existing soil bulk model (Pastor- Zienkiewicz) into an interface model. To calibrate the new interface model, the results of an experimental campaign with the ring shear device under cyclic loading conditions are here presented. The constitutive model shows a good capability to reproduce typical features of sand behaviour such as cyclic compaction and dilatancy, which in saturated partially-drained conditions may lead to liquefaction and cyclic mobility phenomena. [less ▲]

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See detailLe "Löschenhaus" et l'histoire du vandalisme
Scuto, Denis UL

Article for general public (2019)

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See detailExploring the French Web of the 90s
Schafer, Valerie UL

Presentation (2019, June 06)

Panel: National webs Niels Brügger, School of Communication and Culture – Media Studies, Aarhus University Ditte Laursen, Royal Danish Library Friedel Geeraert, State Archives and Royal Library of Belgium ... [more ▼]

Panel: National webs Niels Brügger, School of Communication and Culture – Media Studies, Aarhus University Ditte Laursen, Royal Danish Library Friedel Geeraert, State Archives and Royal Library of Belgium Kees Teszelszky, KB – National Library of the Netherlands Valérie Schafer, University of Luxembourg Daniel Gomes, Arquivo.pt – Fundação para a Ciência e a Tecnologia Opportunities and challenges in collecting and studying national webs A key issue for web archivists (particularly in national libraries) and for scholars alike is the meaning of the national web. Archivists working with legal deposit must work with a definition of their national web, which may be based on the ccTLD, but also on domain registration, the location of servers and/or other criteria. Scholars must then interpret those archives in the light of those definitions. Others studying nations without such legal frameworks face different challenges in working with archives compiled on a selective basis, or with materials held in multiple archives. This panel brings together several of the contributors to ‘The Historical Web and Digital Humanities: The Case of National Webs’, (Routledge, 2019, edited by Niels Brügger and Ditte Laursen). After briefly summarising their own contribution, they will discuss together the particular challenges of defining and then collecting the national web, and on studying the national web with the resulting archives. The panel will be introduced, moderated and concluded by Ditte Laursen & Valérie Schafer. Ditte Laursen (Royal Library, Denmark) investigates how a corpus to support historical study of a national web can be established within national web archives, which usually hold several versions of the same web entity. Examining different datasets from the Danish national web archive 2005–2015, and the different ways these are handled, she demonstrates significant differences between results, with possible implications for research. The Belgian web is currently not systematically archived. Friedel Geeraert (State Archives and Royal Library of Belgium) presents PROMISE, a research project into the feasibility of a sustainable web archiving service for Belgium. She traces the history of the Belgian web from the establishment of the .be domain in 1988 to the present, situating it in its historical, political, and legal context. Kees Teszelszky (KB – National Library of the Netherlands) explores the research opportunities of the Dutch national web for future historians by describing the development and unique characteristics of the Dutch national web. Using traditional historical methods and web archaeology, much historic data can be reconstructed, even though the KB web archive started only in 2007. Valérie Schafer (University of Luxembourg) draws on the experience of the French Web90 project to show the approaches, tools and methodologies used to sketch a broad historical picture of the French web during the 1990s, and the challenges the project faced. No organisation has formal, ongoing responsibility of whole-domain archiving for .eu, one of the largest and most popular European top-level domains, Daniel Gomes (Arquivo.pt) presents an overview of archiving activities related to .eu, including the only known effort to date to archive the entire domain. He also proposes a number of options for sustainable, long-term archiving for .eu. [less ▲]

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See detailBrain health and dementia risk reduction
Leist, Anja UL

Presentation (2019, June 05)

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See detailEpidemiology of and inequalities in ageing
Leist, Anja UL

Presentation (2019, June 05)

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See detailInvestment fund performance validation - Vine copulae estimation using a minimum spanning tree
Petijean, Simon; Schiltz, Jang UL

Scientific Conference (2019, June 03)

Catching the dependencies between financial time series is a complex exer- cise with a lot of challenges, both of theoretical and practical nature. We develop a metho- dology to model portfolio dynamics ... [more ▼]

Catching the dependencies between financial time series is a complex exer- cise with a lot of challenges, both of theoretical and practical nature. We develop a metho- dology to model portfolio dynamics using the minimum spanning tree methods combined with econometric models which solves a good part of these challenges. We use a tracking error that is equivalent to the Euclidean distance, to cluster the closest market indices. Financial risk is difficult to manage, because risk is evolving constantly and depends on very different factors like volatility, liquidity, asset class etc. To capture this evolution we develop a recursive portfolio validation method that reveals the true nature of the evolution of the risk structure of financial portfolios. We investigate several portfolio strategies to understand the dynamics behind the holdings. We thus validate the results of our portfolio analysis. We use a vine copula construction, which allows us to separate the marginal estimation from the dependence estimation and calibrate the underlying dynamics very precisely. The minimum spanning tree method helps us to create a robust tree foundation to support the entire vine structure. Starting from a portfolio analysis, we are thus able to validate the portfolio valuation over a specific period of time. [less ▲]

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See detailŽidé, identita, domov a rodinné dědictví
Bronec, Jakub UL

Scientific Conference (2019, June 01)

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See detailGrenze als multiple (Sozio-)Materialität
Wille, Christian UL

Scientific Conference (2019, June)

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See detailKarlheinz Weber, Ihre Majestät, die Posaune. Eine Entdeckungsreise, crescendo-brass, Würzburg 52017 (12009), illustrations, index, bibliography.
Sagrillo, Damien UL

in IGEB Mitteilungsblatt (2019), 2019(2 / Spring), 4

The author, Karlheinz Weber is one of only a few orchestral musicians and teachers who also approaches his instrument scientifically. The book, a reference work, has now been published in its fifth ... [more ▼]

The author, Karlheinz Weber is one of only a few orchestral musicians and teachers who also approaches his instrument scientifically. The book, a reference work, has now been published in its fifth edition. The subdivision into three main chapters is logically coherent. With 148 pages, the most comprehensive first chapter deals with the trombone’s development in a broad historical context, beginning with Ancient Egypt. [less ▲]

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See detailFlight to Equity and the Market Skewness Risk Premium
Lehnert, Thorsten UL

E-print/Working paper (2019)

Detailed reference viewed: 33 (0 UL)