Evaluation of Kermeta for Solving Graph-based Problems

Kermeta is a meta-language for specifying the structure and behavior of graphs of interconnected objects called models. In this paper,\ud we show that Kermeta is relatively suitable for solving three graph-based\ud problems. First, Kermeta allows the specification of generic model\ud transformations such as refactorings that we apply to different metamodels\ud including Ecore, Java, and Uml. Second, we demonstrate the extensibility\ud of Kermeta to the formal language Alloy using an inter-language model\ud transformation. Kermeta uses Alloy to generate recommendations for\ud completing partially specified models. Third, we show that the Kermeta\ud compiler achieves better execution time and memory performance compared\ud to similar graph-based approaches using a common case study. The\ud three solutions proposed for those graph-based problems and their\ud evaluation with Kermeta according to the criteria of genericity,\ud extensibility, and performance are the main contribution of the paper.\ud Another contribution is the comparison of these solutions with those\ud proposed by other graph-based tools

Transition from plasma- to Kerr-driven laser filamentation

While filaments are generally interpreted as a dynamic balance between Kerr focusing and plasma defocusing, the role of the higher-order Kerr effect (HOKE) is actively debated as a potentially dominant defocusing contribution to filament stabilization. In a pump-probe experiment supported by numerical simulations, we demonstrate the transition between two distinct filamentation regimes at 800\,nm. For long pulses (1.2 ps), the plasma substantially contributes to filamentation, while this contribution vanishes for short pulses (70 fs). These results confirm the occurrence, in adequate conditions, of filamentation driven by the HOKE rather than by plasma.Comment: 6 pages, 4 figures. Accepted for publication in Physical Review Letter

La théorie des systèmes développementaux et la construction sociale des maladies mentales

Dans ce texte, nous proposons un cadre, qui vise à intégrer les contributions des approches constructionnistes et biologiques dans un domaine précis, celui des maladies mentales. Pour ce faire, nous utiliserons quelques propositions récentes faites par des philosophes de la biologie — plus spécifiquement les idées avancées par les tenants de la « théorie des systèmes développementaux » (TSD dans ce qui suit ; Griffiths et Gray, 1994 ; Griffiths et Stoltz, 2000 ; Oyama, 1999) ainsi que la notion d’« enracinement génératif » (generative entrenchment ; Wimsatt, 1986, 1999, 2000).In this paper, we are proposing a framework to integrate the core insights of the constructivist and biological approaches of mental illness. In order to do so, we will use some recent propositions by philosophers of biology, specifically ideas put forth by «developmental system theory» (Griffiths et Gray 1994, Griffiths et Stotz 2000 ; Oyama 1999) and the notion of «generative entrenchment» (Wimsatt 1986, 1999, 2000)

Détermination et diagnostic des modulations des courants statoriques d'une machine asynchrone en présence d'oscillations de couple

National audienceCet article présente une modélisation de la machine asynchrone permettant le diagnostic des modulations des courants statoriques dans le cas d'oscillations du couple de charge. Le modèle proposé est établi en régime permanent pour un système en boucle ouverte. Les composantes oscillatoires du couple de charge entraînent l'apparition de modulations d'amplitude et de modulations de phase sur les courants d'alimentation de la machine. Les caractéristiques de ces modulations dépendent des paramètres électriques et mécaniques, du point de fonctionnement de l'entraînement, de la fréquence des oscillations de couple. Un modèle analytique de l'entraînement, basé sur le modèle d'état linéaire dans le domaine fréquentiel est proposée afin de prédire les composantes spectrales des courants statoriques. Le modèle proposé est validé par des mesures expérimentales

Exploring clinicians\u27 use of evidence-based interventions that treat attachment problems between children, five years of age and under, and their primary caregivers

This exploratory quantitative study was an attempt to address the dearth of research regarding the use of attachment-focused evidence-based treatments (AF EBT) in the clinical setting. Thirty-eight Master’s level or higher licensed mental health clinicians who work with children that are five years old and under, as well as with their primary caregivers, were surveyed via an anonymous web based questionnaire. The survey explored clinicians’ level of awareness, training, use, adaptation, and perceived effectiveness regarding four AF EBTs, as well as potential barriers that may have impeded their use. The AF EBTs were Child-Parent Psychotherapy (CPP), Attachment and Biobehavioral Catch-UP (ABC), Video-feedback Intervention to promote Positive Parenting (VIPP), and Circle of Security (COS). The findings showed that most participants were unfamiliar with the AF EBTs, despite being familiar with attachment theory and favorable toward evidence-based treatments (EBT). Even fewer participants used the AF EBTs. However, those that did, unanimously felt they were effective, with the exception of the ABC intervention. Most respondents adapted the AF EBTs. Without exception, being unaware of the existence of an AF EBT was by far the most commonly cited barrier that impeded its use. The other three most commonly cited barriers were: lack of agency support; difficulty accessing trainings; and not having a need for a new EBT. Implications and future recommendations are discussed. i

Quantitative aspects of the spatial distribution and morphological characteristics of the sea bass (Dicentrarchus labrax L.; Teleostei, Serranidae) trunk lateral line neuromasts.

The results presented herein report quantitative data relative to the distribution and morphological characteristics of both types of neuromasts encountered on the trunk lateral line of the sea bass (Dicentrarchus labrax, L.). These data were obtained from scanning electron micrographs. They indicate that, as expected, each modified scale of the sea bass possessed a single canal neuromast with long axis oriented parallel to the fish's long axis. In contrast to several fish species, two thirds of superficial neuromasts observed herein were oriented perpendicular to the fish's long axis. However, whatever the main orientation of superficial neuromasts, two thirds of their hair bundles were oriented parallel to the long axis of the animal with approximately half of them in the direction of the head. Similar ratios were observed for canal neuromasts whatever the area of the maculae: central or peripheral. For both types of neuromasts it was not possible to clearly distinguish a paired organization of hair bundles with opposing polarities. Superficial neuromasts on each trunk canal scale were located on either the dorsal or ventral side of the canal and appeared to be distributed along the trunk lateral line with a higher probability to be encountered closer to the operculum. The frequency of presence and the average number of superficial neuromasts per scale increased with fish size. We observed a size gradient for canal neuromasts between the operculum and caudal peduncle. This gradation was correlated with a reduction of the width of the central area of the canal segment. Canal neuromasts were always localized in the larger portions of the canal segments. Taken together, these results point out some specific features associated with the sea bass trunk lateral line. With the previous report, they establish the first full description of the trunk lateral line of sea bass and will be useful for upcoming experiments regarding the function of the two types of neuromasts

MENIR : mémoire environnementale Iroise

International audienceLes acteurs de la recherche utilisent pour leurs travaux de multiples sources d'information, qu'elles proviennent de données d'observation ou de références bibliographiques. L'archivage, le catalogage et la description de toutes ces ressources sont les seuls moyens de les pérenniser, de les échanger et d'en garantir une bonne utilisation. Nous présentons ici une démarche de conception d'un système d'information qui répond à ces besoins en s'appuyant sur les concepts d'une "mémoire environnementale" et sur les normes ISO (série 19100). Afin de fournir un outil respectant l'hétérogénéité naturelle de toutes ces informations et de leurs relations nous avons d'abord construit des modèles UML généralistes, que nous particularisons dans une seconde étape. Ces efforts de modélisation sont concrétisés par une phase d'implémentation appliquée à un observatoire du domaine côtier

Surrogate-based diagnosis of mechanical faults in induction motor from stator current measurements

This paper focuses on induction motor monitoring based on stator current measurements. The diagnosis aims at identifying the mechanical faults related to either airgap eccentricity or load torque oscillation. The airgap eccentricity (respectively load torque oscillation) essentially results in an amplitude (respectively phase) modulation of the stator current. Classical spectral analysis allows for the detection but not for the discrimination of these modulations. Time-frequency representations, such as the spectrogram or the Wigner distribution, provide appropriate signatures for fault discrimination. This paper proposes to perform the decision task from the time-frequency representation using the surrogate data technique. In a deterministic context, the phase and amplitude modulations can be considered as non-stationarities since they correspond to time-variations of the signal spectral content. The detection of a modulation is expressed as a binary hypothesis test. The null hypothesis corresponds to a signal without modulation. Stationarized/unmodulated replicas of the observed (possibly modulated) signal are obtained by phase randomization of its Fourier transform. These so-called surrogates provide a reference for the null hypothesis. The observed signal is then compared to these surrogates using appropriate distances in the time-frequency domain. A one-class classifier may be used considering the surrogates as a learning set. This classifier detects outliers corresponding to the modulation and thus to the failures. Moreover, this technique provides the information concerning the predominant type of modulation. This diagnosis method will be tested on simulated and experimental signals