Improving Semantic Transparency of Committee-Designed Languages through Crowd-sourcing

International audienceCommittee-designed languages such as those of the OMG consor-tium are widely used in both industry and academia. These lan-guages seem to be used increasingly by users with no technical background for the visualization, documentation and specification of workflows, data and software systems. However, according to several studies on these languages, the used visual notations do not seem to convey any particular semantics and the recognition of such notations is not perceptually immediate. This lack of se-mantic transparency increases the cognitive load to differentiate concepts from each other and slows down recognition and learning of the language constructs. This paper proposes a process, which leverages the crowd-sourcing to improve the semantic transparency of such languages. We believe that involving end-users in the de-sign process of the languages visual notations should increase the expressiveness of these languages and then their acceptance for a wide range of novice-users

The TopModL Initiative

International audienceWe believe that there is a very strong need for an environment to support research and experiments on model-driven engineering. Therefore we have started the TopModL project, an open-source initiative, with the goal of building a development community to provide: (1) an executable environment for quick and easy experimentation, (2) a set of source files and a compilation tool chain, (3) a web portal to share artefacts developed by the community. The aim of TopModL is to help the model-engineering research community by providing the quickest path between a research idea and a running prototype. In addition, we also want to identify all the possible contributions, understand how to make it easy to integrate existing components, while maintaining architectural integrity. At the time of writing we have almost completed the bootstrap phase (known as Blackhole), which means that we can model TopModL and generate TopModL with TopModL. Beyond this first phase, it is now of paramount importance to gather the best possible description of the requirements of the community involved in model-driven engineering to further develop TopModL, and also to make sure that we are able to reuse or federate existing efforts or goodwill. This paper is more intended to set up a basis for a constructive discussion than to offer definitive answers and closed solutions

Improving Semantic Transparency of Committee-Designed Languages through Crowd-sourcing

International audienceCommittee-designed languages such as those of the OMG consor-tium are widely used in both industry and academia. These lan-guages seem to be used increasingly by users with no technical background for the visualization, documentation and specification of workflows, data and software systems. However, according to several studies on these languages, the used visual notations do not seem to convey any particular semantics and the recognition of such notations is not perceptually immediate. This lack of se-mantic transparency increases the cognitive load to differentiate concepts from each other and slows down recognition and learning of the language constructs. This paper proposes a process, which leverages the crowd-sourcing to improve the semantic transparency of such languages. We believe that involving end-users in the de-sign process of the languages visual notations should increase the expressiveness of these languages and then their acceptance for a wide range of novice-users

In situ monitoring of concrete behavior based on embedded piezoelectric transducers

Dans le domaine de la construction, la détection automatisée et à distance de l’endommagementdes structures en béton est d’une importance capitale. En effet, lescontraintes économiques actuelles imposent une réduction des coûts de maintenancetandis que les impératifs en termes de sécurité et de qualité sont de plus en plus stricts.Dans le cadre de cette thèse, des transducteurs piézoélectriques intégrés sont utilisésafin de suivre en temps réel le comportement du béton. Ces transducteurs sont faitsde PZT, une céramique piézoélectrique particulièrement adaptée au suivi à l’aide d’ultrasonsde par ses faibles dimensions, son faible coût et la large bande de fréquenced’utilisation. Un système de monitoring ultrasonore à faible voltage et ultra rapide a étéentièrement conçu dans le cadre de cette thèse. Le système est basé sur des mesuresultrasonores bilatérales entre un émetteur et un récepteur. Le système d’acquisitiondes données développé permet d’atteindre jusqu’à 150 mesures par seconde et decalculer en temps réel un indice d’endommagement sur base des mesures effectuées.L’indice d’endommagement est basé sur la première partie de l’onde transmise (ondedirecte) plutôt que sur l’onde tardive. Le système a démontré qu’il est capable de détecterl’apparition de fissures dans le béton avant qu’elles ne soient visuellement apparenteset qu’il permet de suivre de suivre l’initiation de l’endommagement jusqu’à la rupturepour des mécanismes de fissuration très rapides, voire fragiles. Le fait d’intégrer lestransducteurs à l’intérieur de la structure permet potentiellement d’améliorer l’efficacitédes transducteurs ultrasonores à condition que les couches d’enrobage de l’élémentpiézoélectrique soient adéquatement choisis. Une partie importante du travail réaliséa été consacrée au développement d’une méthode innovante et fiable pour concevoirde nouveaux designs de transducteurs optimisés à la fois dans du béton frais ou durci.Nous avons choisi de tirer avantage du mode radial de vibration de disques piézoélectriquepeu coûteux au mode de vibration selon l’épaisseur. Ce dernier requiert en effetdes éléments plus épais ou des matériaux piézoélectriques composites plus coûteuxet dès lors peu appropriés à être intégré définitivement dans une structure en béton.Nous démontrons par ailleurs que les matériaux piézoélectriques composites à base dematériaux cimentaires qui sont abondamment étudiés semblent en réalité peu adaptés àêtre utilisés comme transducteurs ultrasonores, contrairement à des composites plusclassiques. Une attention particulière a été portée à comparer le fonctionnement destransducteurs externes et intégrés. Nous montrons par exemple que si les performancesdes transducteurs externes peuvent être améliorées sur base de la théorie d’adaptationde l’impédance acoustique, il en va tout autrement pour les transducteurs intégrésDoctorat en Sciences de l'ingénieur et technologieinfo:eu-repo/semantics/nonPublishe

DREAM: A Distributed Shared Memory model using PVM

Sharing data with the message passing model is not obvious. We propose DREAM an original Distributed Shared Memory (DSM) designed for applications needing to share common data. It can be used at the same time as the message passing model. This paper describes our model DREAM and its implementation using PVM. 1 Introduction The use of tools like PVM, based on the message passing model, makes programming of parallel and distributed architecture easier. Implementation of this model is natural because it has something in common with architecture. Indeed, sites communicate through the communication network by way of messages. But certain problems remain. Lack of common memory, for example, makes the sharing of data more difficult. Different researches have brought about the elaboration of programming models and systems based on Distributed Shared Memory (DSM). Their principle is to provide a memory space "virtually" shared by all the processes of the system or application. Processes can t..

Real-time monitoring of concrete structures using embedded piezoelectric ultrasonic transducers

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From early age assessment of concrete properties to crack detection using embedded ultrasonic transducers

Assessing the concrete properties from very early age is one of the main concerns for contractors. Embedding permanently specific piezoelectric transducers into the structure allows to monitor in real time to evolution of concrete properties which can be extracted from ultrasonic measurements. In the present research, a non-reinforced concrete beam in which embedded piezoelectric transducers are embedded is monitored from very early age to crack appearance. The monitoring system is based on low voltage short pulses excitations signals recorded at high rate (more than 70 ultrasonic measurements per second). The method has demonstrated its great ability for tracking on-line concrete behavior.info:eu-repo/semantics/publishe

Real-time fast ultrasonic monitoring of concrete cracking using embedded piezoelectric transducers

This paper deals with the use of embedded piezoelectric transducers for ultrasonic monitoring of cracking in concrete. Based on the previous developments of our research team on that topic, we design a new data acquisition system which is able to interrogate the emitter-receiver pair up to 150 times per second. The system is based on low-voltage actuation (up to 20 V) and the signal-to-noise ratio is excellent due to the use of a voltage amplifier at the receiver side and the possibility to perform averages. With such a high measurement rate, we are able to follow brittle failure events such as the failure of a concrete cylinder in compression, which is the application example presented. In this application, we show that, in addition to the ultrasonic active monitoring of cracking, the system is also able to record the passive acoustic emission events which can be used as a complementary indicator of damage in the cylinder. We also demonstrate that because of the high level of stresses in compression, the damage indicator defined in our previous studies is not suited for crack monitoring due to the elastoacoustic effect. The amplitude of the first wave arrival is shown to be a robust alternative damage indicator allowing to follow accurately the three successive phases of cracking leading to the failure of the cylinder. © 2017 IOP Publishing Ltd.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Real-time fast ultrasonic monitoring of cracking in a concrete cylinder subject to compression

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