The GUINEVERE project at the VENUS facility

Proc. on CD Rom log315International audienceThe GUINEVERE project is an international project in the framework of IP-EUROTRANS, the FP6 program which aims at addressing the main issues for ADS development in the framework of partitioning and transmutation for nuclear waste volume and radiotoxicity reduction. The GUINEVERE project is carried out in the context of domain 2 of IP-EUROTRANS, ECATS, devoted to specific experiments for the coupling of an accelerator, a target and a subcritical core. These experiments should provide an answer to the questions of online reactivity monitoring, sub-criticality determination and operational procedures (loading, start-up, shutdown, …) in an ADS by 2009-2010. The project has the objective to couple a fast lead core, within the VENUS building operated by the SCK•CEN, with a neutron generator able to work in three different modes: pulsed, continuous and continuous with beam interruptions at the millisecond scale. In order to achieve this goal, the VENUS facility has to be adapted and a modified GENEPI-3C accelerator has to be designed and constructed. The paper describes the main modifications to the reactor core and facility and to the accelerator, which will be executed during the years 2008 and 2009, and the experimental programme which will start in 2009

La prosodie de l’interlangue d’apprenants d’anglais ayant comme L1 le français ou l’espagnol

International audienceLa présente étude réalise une analyse phonétique exploratoire de la prosodie de l’interlangue (IL) des apprenants d’anglais ayant l’espagnol du Chili ou le français de France comme langue maternelle (L1). Nous cherchons à décrire les régularités et les différences dans la manière dont des apprenants et des locuteurs natifs d’anglais réalisent la focalisation, dans le but de déterminer quels mouvements tonals sont privilégiés par chaque groupe de locuteurs, et de comprendre la façon dont ils réalisent la focalisation au niveau suprasegmental. Nous avons étudié notamment les valeurs de f0 et de durée à l’aide de l’algorithme de modélisation Momel. Les résultats montrent des tendances intonatives propres à chaque groupe de locuteurs, liées surtout à la forme et à l’ampleur de leurs mouvements tonals

Acquisition des formes verbales alternantes en français L2: La L1 des apprenants fait-elle la différence?

Acquisition of irregular verb forms in L2 French: does the L1 of the learners explain the difference ? This study explores L1 effects on the production of subject-verb agreement in number (singular vs. plural) in L2 French. L1 influence has rarely been explored in detail in this context, especially compared to other factors such as input frequency of specific verb forms, singular vs plural entities and different types of verbs. In this study, we analyse the use of verbs with an audible distinction between singular and plural in a corpus of 45 narratives produced in L2 French by learners with German, Italian and Swedish as their L1. These three languages display major differences in subjectverb agreement and we therefore hypothesize that it will be easier for learners who express subject-verb agreement in their L1 (Germans and Italians) to produce this agreement in L2 French, compared to learners without subject-verb agreement in their L1 (Swedes). A linear regression analysis confirms an effect of the context (agreement is more correct in singular than in plural contexts) and of the type of verb (agreement is more difficult in verbs with a plural based on a word-final consonant in coda position (e.g. boire 'to drink') compared to verbs with a plural in /5/ (e.g. être 'to be') and in verbs with stem alternation in plural (e.g. prendre 'to take'). However, contrary to predictions, the L1 of the learners did not seem to influence their production of singular and plural verb forms in L2 French. Even though German and Italian clearly express subjectverb agreement in number on the verb, German and Italian learners do not have an advantage over Swedish learners when producing subject-verb agreement in number in L2 French

EUROTRANS/ECATS or neutronic experiments for the validation of XT-ADS and EFIT monitoring

OECD (2011) NEA 6897 ISBN 978926411727

ADS reactivity measurements from MUSE to TRADE (and where do we Go from here?)

International audienceThis paper provides a link between the MUSE (MUltiplication avec SourceExterne) program performed at CEA-Cadarache in France, and the TRADE(TRiga Accelerator Driven Experiment) program performed at ENEA-Casacciain Italy. In both programs, extensive measurements were made to determinethe best methods for sub-criticality measurements in an accelerator-driven system.A very serious attempt was made to quantify the uncertainties associatedwith such measurements. While both MUSE and TRADE studied the methodsof sub-criticality determination, in fact the two systems are very different.MUSE was a fast system with MOX fuel (generation time around 0.5 μs), andTRADE was performed in a TRIGA reactor (generation time around 50 μs).This paper will summarize the important results of these two experiments,with the main purpose being to tie them together to attempt to draw genericconclusions that can be applied in the future to a real ADS.In addition, this paper will briefly discuss the next series of experiments thatwill continue this work in the U.S. (RACE, Reactor Accelerator Coupled Experiments),Belarus (YALINA), Belgium (GUINEVERE), and Russia (SAD,Sub-critical Assembly Dubna). MUSE and TRADE have contributed greatlyto our understanding of the uncertainties associated with sub-critical measurements,but there are still some gaps that must be covered. This paper willdescribe the gaps that exist, and demonstrate how the above future programswill fill in the missing information needed for the design of an actual ADSsystem in the future

The TRADE experiment and progress

TRADE (TRIGA Reactor Accelerator Driven Experiment) will be the demonstration of the coupling of a real spallation source with a sub-critical reactor. TRADE and its motivation are summarised. The experimental work plan of the campaign is presented. The first experiments with the accelerator are scheduled around 2006 or 2007. Some specifics of the TRIGA core are given and particularly about fuel burn-up. Core calculation results with Monte-Carlo and deterministic codes and rods worth obtained during the short campaign of fall 2002 are presented. The comparison between calculated results and this first experiment gives confidence for the follow-up work