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International audience, Trotz der zunehmenden Verbreitung jüngerer bildgebender Verfahren bleibt medizinischer Ultraschall (US) weiterhin ein wichtiges Hilfsmittel bei chirurgischen Eingriffen und der klinischen Diagnose. Viele US-gestützte medizinische Prozeduren erfordern allerdings ausgiebiges Training, so dass es wünschenswert ist, eine realistische Simulation von US-Bildern zur Verfügung zu stellen. Im Gegensatz zu früheren Ansätzen simulieren wir solche Bilder auf der "Graphics Processing Unit". Wir erweitern hierzu eine Methode, die von Wein et al. für die Abschätzung von US-Reflexionen aus Daten der Computertomographie (CT) vorgeschlagen wurde, zu einer leichter zu berechnenden Form. Zusätzlich schätzen wir die US-Absorption aus den CT-Daten ab. Mit Hilfe von NVIDIAs "Compute Unified Device Architecture" (CUDA) simulieren wir Reflexion, Verschattung, Rauschen und radiale Unschärfe, ausgehend von unbearbeiteten CT-Daten in Echtzeit und ohne Vorausberechnung.

International audience, The pub/sub communication style is a prevalent messaging pattern for filtering information from distributed and large-scale network (e.g., from the real-time web, sensor networks, etc.) thanks to the decou- pling between publishers and subscribers. At the same time, persisting the published information is a prerequisite for any further batch analyt- ics on such big amount of data. As data can be heterogeneous, reliance on format from the semantic web such as RDF is unavoidable. In this paper we introduce two versions of a content-based pub/sub matching algorithm for RDF described events, working on an adapted version of the CAN structured P2P network designed to both store and dissemi- nate RDF events. In contrary to existing pub/sub solutions based upon structured overlay networks that index semantic events several times due to the use of hash functions, we leverage the lexicographic order of the event elements. Thus, only subscriptions and not publications have to be duplicated, which is better given that in real settings, publications may occur more frequently than subscriptions. Furthermore, our system al- lows to publish events made of any number of elements and the subscrip- tion language leverages the SPARQL query language. The first algorithm we introduce initially derives from the ideas discussed by Liarou. et al. based upon rewriting continuous queries along matching RDF elements (CSBV) with the purpose to perform the matching between subscriptions and several RDF elements on multiple nodes. The experimental results discuss the applicability of the presented algorithms to some synthetic scenarios and identify, accordingly, which pub/sub matching algorithm is the more relevant.

International audience, Telecommunication services are widespread and subject today to tensions on a competitive market. Telecommunication service design is more and more software oriented. To reduce time to market and cost of services, a service designer better need to simulate and evaluate his design earlier. The approach proposed in this paper is to reduce the abstraction gap between modeling and simulation phases using model transformation. But manual transformations are so far time consuming and error prone. As a trustworthy solution, model based techniques and associated transformations permit to systematically link service models with simulation phase before realization. We thus propose as a first contribution a meta-model dedicated to concepts of IP Multimedia Subsystem core network as a case study. Our meta-model constrains and defines such network entities to be used in the code generation, which is our second contribution. The implementation of a video conference service permits to illustrate our workbench.