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See detailAutomating Free Logic in HOL, with an Experimental Application in Category Theory
Benzmüller, Christoph UL; Scott, Dana

in Journal of Automated Reasoning (2019)

A shallow semantical embedding of free logic in classical higher-order logic is presented, which enables the off-the-shelf application of higher-order interactive and automated theorem provers for the ... [more ▼]

A shallow semantical embedding of free logic in classical higher-order logic is presented, which enables the off-the-shelf application of higher-order interactive and automated theorem provers for the formalisation andverification of free logic theories. Subsequently, this approach is applied to aselected domain of mathematics: starting from a generalization of the standardaxioms for a monoid we present a stepwise development of various, mutuallyequivalent foundational axiom systems for category theory. As a side-effect ofthis work some (minor) issues in a prominent category theory textbook havebeen revealed.The purpose of this article is not to claim any novel results in category the-ory, but to demonstrate an elegant way to “implement” and utilize interactiveand automated reasoning in free logic, and to present illustrative experiments. [less ▲]

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See detailBRIDGE MONITORING WITH HARMONIC EXCITATION AND PRINCIPAL COMPONENT ANALYSIS
Nguyen, Viet Ha UL; Golinval, Jean-Claude; Maas, Stefan UL

in The Baltic Journal of Road and Bridge Engineering (2019)

Principal Component Analysis is used for damage detection in structures excited by harmonic forces. Time responses are directly analysed by Singular Value Decomposition to deduct two dominant Proper ... [more ▼]

Principal Component Analysis is used for damage detection in structures excited by harmonic forces. Time responses are directly analysed by Singular Value Decomposition to deduct two dominant Proper Orthogonal Values corresponding to two Proper Orthogonal Modes. Damage index is defined by the concept of subspace angle that a subspace is built from the two Proper Orthogonal Modes. A subspace angle reflects the coherence between two different structural health states. An example is given through the application on a part of a real prestressed concrete bridge in Luxembourg where different damage states were created by cutting a number of prestressed tendons in four scenarios with increasing levels. Results are better by using excitation frequency close to an eigenfrequency of the structure. The technique is convenient for practical application in operational bridge structures. [less ▲]

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See detailStructural framework conditions and individual motivations for youth-mobility: A macro-micro level approach for different European country-types
Hemming, Karen; Schlimbach, Tabea; Tilmann, Frank et al

in Migration Letters (2019), 16(1), 45-59

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See detailA Pedagogical Note on Risk Sharing Versus Instability in International Financial Integration: When Obstfeld Meets Stiglitz
Boucekkine, Raouf; Zou, Benteng UL

in Open Economies Review (2019)

The pure risk sharing mechanism implies that financial liberalization is growth enhancing for all countries as the world portfolio shifts from safe low-yield capital to riskier high-yield capital. This ... [more ▼]

The pure risk sharing mechanism implies that financial liberalization is growth enhancing for all countries as the world portfolio shifts from safe low-yield capital to riskier high-yield capital. This result is typically obtained under the assumption that the volatilities for risky assets prevailing under autarky are not altered after liberalization. We relax this assumption within a simple two-country model of intertemporal portfolio choices. By doing so, we put together the risk sharing effect and a well defined instability effect. We identify the conditions under which liberalization may cause a drop in growth. These conditions combine the typical threshold conditions outlined in the literature, which concern the deep characteristics of the economies, and size conditions on the instability effect induced by liberalization. [less ▲]

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See detailClimate politics: how public persuasion affects the trade-off between environmental and economic performance
Prieur, Fabien; Zou, Benteng UL

in Mathematical Social Sciences (2019)

This paper aims at studying the impact of public persuasion, through information dissemination, on environmental and economic performance. A differential game in which opposite interest groups compete for ... [more ▼]

This paper aims at studying the impact of public persuasion, through information dissemination, on environmental and economic performance. A differential game in which opposite interest groups compete for bringing the majority’s environmental concern closer to their views is developed. The results show a strong asymmetry in the impact of public persuasion. It may bring the median voter economy closer to the social optimum in the long run, thereby reducing environmental and economic distorsions. But this only occurs when the environmental group exhibits a radical ideology and people are initially closer to the industrialists’ views. By contrast, economies where industrial groups are powerful and strongly opposed to environmental protection never benefit from the outcome of the game of persuasion. This may explain why the US have failed to take action on global warming up to now. [less ▲]

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See detailTo MigrateWith orWithout Ones’ Children in China - That is the Question
Chen, Yiwen UL; Fromentin, Vincent; Zou, Benteng UL

in Annals of Eceonomcis and statistics (2019)

Where should Chinese internal migrant parents locate their school-aged children: migrate with them or leave them behind? And should they invest in private education of their children? We investigate ... [more ▼]

Where should Chinese internal migrant parents locate their school-aged children: migrate with them or leave them behind? And should they invest in private education of their children? We investigate whether migrant parents can afford to take their children to migrate and thus provide theoretical optimum that maximizes migrant parents’ utility which includes the children’s educational performance. Depending on the educational investment parents make and the relocation cost of children, we provide necessary and sufficient conditions under which migrant parents should take their children to migrate and conditions under which migrant parents should provide their children with private education. [less ▲]

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See detailPierre Werner and Europe: The Family Archives Behind the Werner Report.
Danescu, Elena UL

Book published by Palgrave Macmillan (2018)

Detailed reference viewed: 58 (25 UL)
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See detailGermany, Greece and Poland: The Complicated story of Reparations and their impact on European (dis?) Integration,
Paravantis, Spero UL

in Paravantis, Spero (Ed.) BENELUX, Europe and the Cold War: Asymmetrical cold war power relations in the Integration process of Europe (2018)

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See detailGenome-wide mega-analysis identifies 16 loci and highlights diverse biological mechanisms in the common epilepsies
The International League Against Epilepsy Consortium on Complex Epilepsies; Krause, Roland UL

in Nature Communications (2018)

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See detailLe Mouvement écologique dans les longues années 1960
Scuto, Denis UL

Article for general public (2018)

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See detailLes “petites classes moyennes” se vivent comme les suivants sur la liste des victimes
Chauvel, Louis UL

Article for general public (2018)

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See detailLSRepair: Live Search of Fix Ingredients for Automated Program Repair
Liu, Kui UL; Koyuncu, Anil UL; Kim, Kisub UL et al

Scientific Conference (2018, December 07)

Automated program repair (APR) has extensively been developed by leveraging search-based techniques, in which fix ingredients are explored and identified in different granularities from a specific search ... [more ▼]

Automated program repair (APR) has extensively been developed by leveraging search-based techniques, in which fix ingredients are explored and identified in different granularities from a specific search space. State-of-the approaches often find fix ingredients by using mutation operators or leveraging manually-crafted templates. We argue that the fix ingredients can be searched in an online mode, leveraging code search techniques to find potentially-fixed versions of buggy code fragments from which repair actions can be extracted. In this study, we present an APR tool, LSRepair, that automatically explores code repositories to search for fix ingredients at the method-level granularity with three strategies of similar code search. Our preliminary evaluation shows that code search can drive a faster fix process (some bugs are fixed in a few seconds). LSRepair helps repair 19 bugs from the Defects4J benchmark successfully. We expect our approach to open new directions for fixing multiple-lines bugs. [less ▲]

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See detailArchives du Web, « le dur » à l’épreuve de la durée
Schafer, Valerie UL

Presentation (2018, December 04)

Avec 336 milliards de pages Web collectées depuis 1996, la fondation Internet Archive propose un voyage temporel dans la Toile du passé qui a de quoi impressionner le chercheur et n’a rien à envier à la ... [more ▼]

Avec 336 milliards de pages Web collectées depuis 1996, la fondation Internet Archive propose un voyage temporel dans la Toile du passé qui a de quoi impressionner le chercheur et n’a rien à envier à la masse de tweets récupérés par la Library of Congress suite à un accord avec Twitter en 2010. Au plan national aussi nos institutions d’archivage - la Bibliothèque nationale de France (BnF) et l’Institut national de l’audiovisuel (Ina), collectent des volumes impressionnants (plus de 20 milliards de tweets archivés à la suite des attentats de novembre 2015 par l’Ina), invitant les chercheurs à penser des lectures et analyses outillées par des moyens informatiques afin d’approcher ces masses de données. Après avoir montré dans quelle mesure chercheurs et institutions d’archivage ont pu proposer un virage vers la lecture distante en matière d’archives du Web, nous interrogerons les enjeux et limites du traitement de ces sources nativement numériques par des méthodes computationnelles ou encore des outils relevant des humanités numériques. Entre archives enfermées dans les enceintes des bibliothèques en vertu du dépôt légal, opacité de certaines collectes, lacune des fonds et division du travail de collecte et d’analyse, singularité des corpus et difficulté à les pérenniser ou encore à les partager, il s’agira enfin de proposer des pistes à la question : « Faut-il et le cas échéant où durcir les analyses liées aux archives du Web ? ». [less ▲]

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See detailJewish responses to anti-Semitism in Paris and London in the late 1930s as European Jewish political history
Zaagsma, Gerben UL

in Bajohr, Frank; Löw, Andrea; Wirsching, Andreas (Eds.) Right-Wing Politics and the Rise of Antisemitism in Europe 1935-1941 (2018)

This article compares Jewish responses to antisemitism in Paris and London in the late 1930s, when antisemitism was on the rise in both France and the United Kingdom. There were striking similarities in ... [more ▼]

This article compares Jewish responses to antisemitism in Paris and London in the late 1930s, when antisemitism was on the rise in both France and the United Kingdom. There were striking similarities in these responses, yet local contexts and circumstances dominate the historiographies of both cases. The main aim of this article, then, is not so much to offer new insights into the individual cases (both of which have been abundantly analyzed in historical research), but rather to fill a gap by examining the broader factors that account for these similarities. On the one hand, the article examines the nature of Jewish self-identification in the post-Emancipation era and its effects on the political cultures, practices, and identifications of the actors that were involved; on the other, it explores the way in which these practices were also shaped by migration and transnational aspects. Ultimately, this case study will argue for a comparative and transnational approach to Jewish political history in order to arrive at a better understanding of its diverse configurations and permutations. [less ▲]

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See detailOsiris: Hunting for Integer Bugs in Ethereum Smart Contracts
Ferreira Torres, Christof UL; Schütte, Julian; State, Radu UL

in 34th Annual Computer Security Applications Conference (ACSAC ’18), San Juan, Puerto Rico, USA, December 3-7, 2018 (2018, December)

The capability of executing so-called smart contracts in a decentralised manner is one of the compelling features of modern blockchains. Smart contracts are fully fledged programs which cannot be changed ... [more ▼]

The capability of executing so-called smart contracts in a decentralised manner is one of the compelling features of modern blockchains. Smart contracts are fully fledged programs which cannot be changed once deployed to the blockchain. They typically implement the business logic of distributed apps and carry billions of dollars worth of coins. In that respect, it is imperative that smart contracts are correct and have no vulnerabilities or bugs. However, research has identified different classes of vulnerabilities in smart contracts, some of which led to prominent multi-million dollar fraud cases. In this paper we focus on vulnerabilities related to integer bugs, a class of bugs that is particularly difficult to avoid due to some characteristics of the Ethereum Virtual Machine and the Solidity programming language. In this paper we introduce Osiris – a framework that combines symbolic execution and taint analysis, in order to accurately find integer bugs in Ethereum smart contracts. Osiris detects a greater range of bugs than existing tools, while providing a better specificity of its detection. We have evaluated its performance on a large experimental dataset containing more than 1.2 million smart contracts. We found that 42,108 contracts contain integer bugs. Be- sides being able to identify several vulnerabilities that have been reported in the past few months, we were also able to identify a yet unknown critical vulnerability in a couple of smart contracts that are currently deployed on the Ethereum blockchain. [less ▲]

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See detailQualitätskonstruktionen - Zur Verarbeitung divergierender Qualitätsanforderungen in der Jugendarbeit
Biewers, Sandra UL

Book published by Beltz Juventa (2018)

Formale Verfahren zur Sicherung von Qualität in sozialpädagogischen Organisationen stehen meist in einem engen Zusammenhang mit Fragen der Wirtschaftlichkeit. Ob sie auch in der pädagogischen Praxis ... [more ▼]

Formale Verfahren zur Sicherung von Qualität in sozialpädagogischen Organisationen stehen meist in einem engen Zusammenhang mit Fragen der Wirtschaftlichkeit. Ob sie auch in der pädagogischen Praxis nutzbringend zur Anwendung kommen und aus ihnen auch fachliche Innovationen hervorgehen, steht aber häufig in Zweifel. Das vorliegende Buch befasst sich mit dieser Frage aus der Perspektive der sozialpädagogischen Praxis. Vorgestellt wird eine empirische Studie, die mit Rekurs auf neoinstitutionalistische Theoriekonzepte untersucht, anhand welcher Strategien Fachkräfte in der Offenen Jugendarbeit die meist von staatlicher Seite definierten Qualitätskriterien und -regeln in ihrem Praxisalltag aufgreifen und ob bzw. inwiefern sie diese nach professionellen Anforderungen reinterpretieren und transformieren [less ▲]

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See detailCollaborative Data Delivery for Smart City-oriented Mobile Crowdsensing Systems
Vitello, Piergiorgio; Capponi, Andrea UL; Fiandrino, Claudio UL et al

in IEEE Global Communications Conference (GLOBECOM), Abu Dhabi, UAE, 2018 (2018, December)

The huge increase of population living in cities calls for a sustainable urban development. Mobile crowdsensing (MCS) leverages participation of active citizens to improve performance of existing sensing ... [more ▼]

The huge increase of population living in cities calls for a sustainable urban development. Mobile crowdsensing (MCS) leverages participation of active citizens to improve performance of existing sensing infrastructures. In typical MCS systems, sensing tasks are allocated and reported on individual-basis. In this paper, we investigate on collaboration among users for data delivery as it brings a number of benefits for both users and sensing campaign organizers and leads to better coordination and use of resources. By taking advantage from proximity, users can employ device-to-device (D2D) communications like Wi-Fi Direct that are more energy efficient than 3G/4G technology. In such scenario, once a group is set, one of its member is elected to be the owner and perform data forwarding to the collector. The efficiency of forming groups and electing suitable owners defines the efficiency of the whole collaborative-based system. This paper proposes three policies optimized for MCS that are compliant with current Android implementation of Wi-Fi Direct. The evaluation results, obtained using CrowdSenSim simulator, demonstrate that collaborative-based approaches outperform significantly individual-based approaches. [less ▲]

Detailed reference viewed: 63 (8 UL)