The TASTE Toolset: turning human designed heterogeneous systems into computer built homogeneous software

International audienceThe TASTE tool-set results from spin-off studies of the ASSERT project, which started in 2004 with the objective to propose innovative and pragmatic solutions to develop real-time software. One of the primary targets was satellite flight software, but it appeared quickly that their characteristics were shared among various embedded systems. The solutions that we developed now comprise a process and several tools ; the development process is based on the idea that real-time, embedded systems are heterogeneous by nature and that a unique UML-like language was not helping neither their construction, nor their validation. Rather than inventing yet another "ultimate" language, TASTE makes the link between existing and mature technologies such as Simulink, SDL, ASN.1, C, Ada, and generates complete, homogeneous software-based systems that one can straightforwardly download and execute on a physical target. Our current prototype is moving toward a marketed product, and sequel studies are already in place to support, among others, FPGA systems

Modélisation numérique de structures en pisé : analyses et recommandations

International audienceL'utilisation du pisé dans la construction s'avère aujourd'hui intéressante dans la nécessaire démarche de bâtir durable. Ce matériau, non transformé industriellement, est porteur d'une énergie grise proche de zéro. De plus, les constructions en pisé apportent un bon confort d'habitation grâce au comportement hygrothermique naturel des murs en terre. Ces remarques participent à un regain d'intérêt pour ce matériau comme le montrent les récentes recherches sur le sujet. Pourtant, des verrous scientifiques persistent dans ce domaine. Peu d'études concernent, en particulier, l'évaluation des performances mécaniques sous sollicitations dynamiques. Cet article présente, dans un premier temps, une revue d'études existantes. Dans un deuxième temps, des simulations numériques ont été menées à l'aide du code d'éléments finis (ASTER). La loi de comportement Drucker-Pager avec écrouissage a été retenue pour les simulations. La pertinence de ce modèle et les paramètres prépondérants ont également été mis en avant par comparaison avec des données expérimentales issues de la littérature

Seismic Assessment of Rammed Earth Walls Using Pushover Tests

AbstractRammed earth (RE) construction is attracting renewed interest throughout the world thanks to its sustainable characteristics: a very low embodied energy, an advantageous living comfort due to a substantial thermal inertia, good natural moisture buffering, and an attractive appearance. This is why several studies have been carried out recently to investigate RE. However, there have not yet been sufficient studies on the seismic performance of RE buildings.This paper presents an experimental study on the static nonlinear pushover method and its application on the seismic performance of RE structures. Several walls with two height/length ratios were built and tested to obtain the nonlinear “shear force–displacement” curves. By transposing to the “acceleration-displacement” system and by using the standard spectra presented in Eurocode 8, the performance points could be determined which enabled to assess the seismic performance of the studied walls in different conditions (seismicity zones and soil types)

Identification et localisation des impacts par analyse inverse - Poutre et plaque

L’estimation des forces d’impact par des mesures directes, pour des structures qui sont dans des conditions réelles d’utilisation, est en pratique très difficile voire même impossible. Pour répondre à ce besoin il est souvent fait recours aux méthodes inverses, qui correspondent à la démarche inverse du problème direct : des réponses mesurées sur une structure donnée sont exploitées pour tenter d’en identifier les causes, qui en sont à l’origine. L'approche conduit à créer des fonctions de transfert entre les points d'impact et de mesure sur la structure que ce soit expérimentalement ou numériquement, à mesurer les réponses, et à reconstruire l’effort par déconvolution du signal. Il est connu que ce type de problème est souvent mal posé, et que les solutions trouvées peuvent ne pas être représentatives du problème réel, du fait de bruits de mesures. Pour obtenir une solution stable avec un sens physique, nous utilisons l’une des méthodes classiques de régularisation, tels que Tikhonov qui semble la plus appropriée. Le problème de caractérisation de l'impact devient plus complexe lorsque le point d’impact est inconnu, par conséquent, nous devons créer les fonctions de transfert entre plusieurs points d'impact et de mesure, et minimiser la fonctionnelle permettant dans un premier temps de localiser l’impact, et dans un second temps d’identifier la force d’impact

Safety and diagnostic yield of renal biopsy in the intensive care unit

Purpose Renal biopsy (RB) is occasionally performed in critically ill patients. The safety and impact of RB in this setting have not been reported. Methods A 10-year (2000–2009) retrospective multicentre study was conducted in ten French intensive care units (ICU) on patients who underwent RB during their management. Medical files were retrieved for data analysis. Results Seventy-seven patients underwent an RB of which 68 (88 %) were on a native kidney and 9 (12 %) on a transplanted kidney. Percutaneous ultrasound-guided RB was used in most cases (87 %). Fifty-seven per cent of the patients were on mechanical ventilation at the time of RB. RB-related complications occurred in 17 (22 %) patients, two were graded as severe (requirement for kidney embolization, eventually successful). In 35 (51 %) non-transplanted patients, RB established a specific diagnosis other than acute tubular necrosis (ATN), which was diagnosed in only 18 % of patients. In the remaining patients, only non-specific lesions were observed. Therapeutic modifications followed RB in 14 (21 %) non-transplanted patients. Presence of signs of systemic disease involving the renal tract, occurrence of renal failure before hospital admission, and absence of any factor usually associated with ATN significantly predicted the presence of a specific diagnosis at RB other than ATN. Conclusions In this cohort, the contribution of RB to diagnosis and treatment was undeniable, but at the expense of frequent adverse events although most of them were not considered severe

The ANTENATAL multicentre study to predict postnatal renal outcome in fetuses with posterior urethral valves: objectives and design

Abstract Background Posterior urethral valves (PUV) account for 17% of paediatric end-stage renal disease. A major issue in the management of PUV is prenatal prediction of postnatal renal function. Fetal ultrasound and fetal urine biochemistry are currently employed for this prediction, but clearly lack precision. We previously developed a fetal urine peptide signature that predicted in utero with high precision postnatal renal function in fetuses with PUV. We describe here the objectives and design of the prospective international multicentre ANTENATAL (multicentre validation of a fetal urine peptidome-based classifier to predict postnatal renal function in posterior urethral valves) study, set up to validate this fetal urine peptide signature. Methods Participants will be PUV pregnancies enrolled from 2017 to 2021 and followed up until 2023 in >30 European centres endorsed and supported by European reference networks for rare urological disorders (ERN eUROGEN) and rare kidney diseases (ERN ERKNet). The endpoint will be renal/patient survival at 2 years postnatally. Assuming α = 0.05, 1–β = 0.8 and a mean prevalence of severe renal outcome in PUV individuals of 0.35, 400 patients need to be enrolled to validate the previously reported sensitivity and specificity of the peptide signature. Results In this largest multicentre study of antenatally detected PUV, we anticipate bringing a novel tool to the clinic. Based on urinary peptides and potentially amended in the future with additional omics traits, this tool will be able to precisely quantify postnatal renal survival in PUV pregnancies. The main limitation of the employed approach is the need for specialized equipment. Conclusions Accurate risk assessment in the prenatal period should strongly improve the management of fetuses with PUV

Behavior of a structurally dissipating rock-shed: experimental analysis and study of punching effects

International audienc

Simulation of a block impacting a reinforced concrete slab with a finite element model and a mass-spring system

International audienc