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International audience; Data Mashup is a special class of applications mashup thatcombines data elements from multiple data sources (that are often ex-ported as data web services) to respond to transient business needs onthe y. In this paper, we propose a semantic model for data servicesalong with a declarative approach for creating data mashups withoutany programming involved. Given a query formulated over domain on-tologies, and a set of preferences modeled using the fuzzy set theory,our approach selects the relevant data services based on their semanticmodeling using an RDF query rewriting algorithm. Selected services arethen orchestrated using a ranking-aware algebra to rank their returnedresults based on users preferences at the data mashup execution time.

International audience; Toxoplasma gondii is a highly successful parasite that is thought to infect nearly one third of the world's population. Molecular epidemiology studies have illuminated the population structure of T. gondii strains world-wide and enabled insights into how the parasite is transmitted and the frequency of genetic exchange. Toxoplasma population genetics studies have shown that in North America and Europe, three genotypes have predominated whereas other diverse genotypes have propagated in other parts of the world, particularly in Central and South America. This chapter summarizes the techniques used to understand the population structure of T. gondii and how these techniques have also been helpful in understanding outbreaks of toxoplasmosis. As technology has advanced, more in-depth studies have facilitated our understanding of how differing genotypes can be linked to biological phenotypes including human disease.

International audience; Orchestras of Digital Musical Instruments (DMIs) enable new musical collaboration possibilities, extending those of acoustic and electric orchestras. However the creation and development of these orchestras remain constrained. In fact, each new musical collaboration system or orchestra piece relies on a fixed number of musicians, a fixed set of instruments (often only one), and a fixed subset of possible modes of collaboration. In this paper, we describe a unified framework that enables the design of Digital Orchestras with potentially different DMIs and an expand-able set of collaboration modes. It relies on research done on analysis and classification of traditional and digital orchestras, on research in Collaborative Virtual Environments, and on interviews of musicians and composers. The BOEUF framework consists of a classification of modes of collaboration and a set of components for modelling digital orchestras. Integrating this framework into DMIs will enable advanced musical collaboration modes to be used in any digital orchestra, including spontaneous jam sessions.

International audience; We study unlimited infinite churn in peer-to-peer overlay networks. Under this churn, arbitrary many peers may concurrently request to join or leave the overlay network; moreover these requests may never stop coming. We prove that unlimited adversarial churn, where processes may just exit the overlay network, is unsolvable. We focus on cooperative churn where exiting processes participate in the churn handling algorithm. We define the problem of unlimited infinite churn in this setting. We distinguish the fair version of the problem, where each request is eventually satisfied, from the unfair version that just guarantees progress. We focus on local solutions to the problem, and prove that a local solution to the Fair Infinite Unlimited Churn is impossible. We then present our algorithm UIUC that solves the Unfair Infinite Unlimited Churn Problem for a linearized peer-to-peer overlay network. We extend this solution to skip lists and skip graphs.

International audience; Local Policy Search is a popular reinforcement learning approach for handling large state spaces. Formally, it searches locally in a parameterized policy space in order to maximize the associated value function averaged over some pre-defined distribution. The best one can hope in general from such an approach is to get a local optimum of this criterion. The first contribution of this article is the following surprising result: if the policy space is convex, any (approximate) local optimum enjoys a global performance guarantee. Unfortunately, the convexity assumption is strong: it is not satisfied by commonly used parameterizations and designing a parameterization that induces this property seems hard. A natural so-lution to alleviate this issue consists in deriving an algorithm that solves the local policy search problem using a boosting approach (constrained to the convex hull of the policy space). The resulting algorithm turns out to be a slight generalization of conservative policy iteration; thus, our second contribution is to highlight an original connection between local policy search and approximate dynamic pro-gramming.

Learning interventions based on modules are common in computer science education. Traditional learning modules that present a large amount of content in a linear format can lead to students skimming and skipping content resulting in lower student engagement and effectiveness. In this paper, we present theoretical support for increasing engagement and effectiveness of learning modules, describe a system that implements these principles, and discuss the results of a study across four sections of CS0. Using the Security Injections @Towson cybersecurity modules, we enhanced select modules by incorporating the e-learning design principles of segmentation and interactivity. The study compares student engagement between the current (1.0) modules and the enhanced (2.0) modules. The use of the enhanced (2.0) modules significantly increased student engagement and these results persisted across gender and race. Feedback from instructors indicates higher student and instructor interest in the enhanced modules; in spring 2015, more than 20 instructors are using the enhanced (2.0) modules.

International audience; The relative efficiency of auctions and negotiations is still a puzzle in the literature. While auctions are the prescribed procedures and the most used ones for public procurement, in the private sector, where buyers are free to choose their purchasing method, competitive tendering is far from being their preferred option (Bajari et al. 2009). In addition, recent empirical studies (Estache et al. 2009, Bajari et al. 2009) highlight some failures of auction procedures and identify conditions under which negotiation is more efficient. In particular, they show that auctions perform poorly when projects are complex. In this paper, our aim is to contribute to this debate by providing an empirical analysis of how awarding mechanisms are chosen in public procurement in France. To this end, we examine a comprehensive database of 76,188 observations corresponding to the entire set of public procurement work contracts awarded between 2005 and 2007 in the construction sector. We find empirical regularities regarding the choice of awarding procedures by public buyers. However, most of these regularities do not coincide with what the theoretical literature considers as transaction-cost minimizing behaviours. In particular, the size of the construction projects as well as the length of contracts do not appear as key determinants of the choice of awarding procedures, which translates into costly renegotiations.

Aluminum based hybrid composites were produced from recycled AA7075 chips with the addition of TiC (d ≤ 3–5 micron), MoS2 and Al2O3 fiber. In the two groups of composites produced, the content of MoS2 and Al2O3 were fixed as 2 wt % and 3 wt % respectively, whereas TiC content was at two levels (5–10%). The combined method of powder metallurgy route, sintering followed by forging, was used to manufacture these composites. These composites are targeted for aeronautical and automotive industries for components subjected to static as well as cyclic and dynamic loading. In addition to mechanical properties, machinability of these composites is of importance hence, MoS2 was included in the formulation. Micro hardness, 3 point bending, low velocity impact and nanoindentation (creep and wear) tests were performed on samples manufactured by just sintering and sintering followed by forging. The results showed that, in generals, the samples that were forged after sintering yielded better properties. The microstructure analyses (matrix/interface) have been carried out by Scanning Electron Microscope (SEM).

International audience; The corrosion process (oxidation and hydriding) of the zirconium alloy cladding is one of the limiting factors on the fuel rod lifetime, in particular for the Zircaloy-4 alloy. The corrosion rate of this alloy shows indeed a great acceleration at high burn-up in Light Water Reactors. Understanding the corrosion behavior under irradiation for this alloy is an important technological issue for the safety and efficiency of LWRs. In particular, understanding the effect of irradiation on the metal and the oxide layers is a key parameter in the study of corrosion behavior of zirconium alloys. Zircaloy-4 samples have undergone helium and proton ion-irradiation up to 0.3 dpa forming a uniform defect distribution up to 1 µm deep. Both as-received and pre-corroded samples have been irradiated in order to compare the effect of metal irradiation to that of oxide layer irradiation. After irradiation, samples have been corroded in order to study the impact of irradiation defects in the metal and in pre-existing oxide layers on the formation of new oxide layers. Synchrotron X-ray micro-diffraction and micro-fluorescence are used to follow the evolution of oxide crystallographic phases, texture and stoichiometry both in the metal and in the oxide in cross-section. In particular, the tetragonal oxide phase fraction, which has been known to have an important role on corrosion behavior, is mapped in both unirradiated and irradiated metal at the sub-micron scale and appears to be significantly affected by irradiation. These observations, complemented with electron microscopy analyses on samples in carefully chosen areas of interest are combined in order to fully characterize changes due to irradiation in metal and oxide phases of both alloys.

The current industrial revolution is said to be driven by the digitization that exploits connected information across all aspects of manufacturing. Standards have been recognized as an important enabler. Ontology-based information standard may provide benefits not offered by current information standards. Although there have been ontologies developed in the industrial manufacturing domain, they have been fragmented and inconsistent, and little has received a standard status. With successes in developing coherent ontologies in the biological, biomedical, and financial domains, an effort called Industrial Ontologies Foundry (IOF) has been formed to pursue the same goal for the industrial manufacturing domain. However, developing a coherent ontology covering the entire industrial manufacturing domain has been known to be a mountainous challenge because of the multidisciplinary nature of manufacturing. To manage the scope and expectations, the IOF community kicked-off its effort with a proof-of-concept (POC) project. This paper describes the developments within the project. It also provides a brief update on the IOF organizational set up.