Frequency and voltage control schemes for three-phase grid-forming inverters

Grid-forming inverters play an important role in supporting power systems with low rotational inertia. Their frequency and voltage control policies must guarantee a synchronised operation, accurate power sharing amongst inverters, and a good transient response. Simultaneously achieving the latter two requirements is in general a non-trivial problem and existing schemes in the literature often focus on one of these two aspects. In this paper, we propose a simple frequency controller that uses the inverter output current as feedback to adapt its frequency, and also propose controllers for the regulation of the DC and AC voltages. We show that the proposed control architectures achieve both power sharing without a communication link, and desirable passivity properties that can enhance the dynamic performance. Closed loop stability of the grid-forming inverter with a dynamic load is also proven and simulations on advanced models are carried out to validate the results.ERC starting grant 67977

La Génesis del monstruo en estrella distante

En este artículo estudiamos cómo se gesta, en la novela Estrella distante, no sólo el Mal absoluto, sino la figura del monstruo encarnado en el personaje Alberto Ruiz-­-Tagle, alias Carlos Wieder. Luego de una incursión en la temática del doble, y basándonos en determinados casos en detalles del discurso narrativo, mostramos cómo el texto propone el nacimiento del monstruo y la configuración del personaje central como "Anticristo". Para ello se establecen nexos intertextuales con la película de Polanski, Rosemary's Baby, y la resonancia de los ecos de La resistible ascensión de Arturo Ui, de Bertolt Brecht.In this paper we study, in the novel Estrella distante, not only the developement of Absolute evil, but also the figure of the monster characterized by Alberto Ruiz-­-Tagle, alias Carlos Wieder. After an entrance into the theme of the double, and in some cases based on narrative details, we show how the text proposes the birth of the monster and the configuration of the central character as the "Antichrist", establishing intertextual connections with Polanski'sh film, Rosemary's Baby, and the resonance of the echoes of La resistible ascensión de Arturo Ui, of Bertolt Brecht

Le syndrome d’apert

Le syndrome d’Apert est une affection congénitale rare, caractérisée par une sténose cranio-faciale associée à une syndactylie des mains et des pieds. Sa prise en charge doit être précoce et multidisciplinaire. Sa gravité réside dans la coexistence de plusieurs malformations avec un risque d’hypertension intracrânienne chronique responsable d’une cécité et d’une débilité mentale. Les auteurs rapportent une nouvelle observation à travers laquelle ils illustrent les aspects cliniques et évolutifs ainsi que les difficultés thérapeutiques de cette affection.Pan African Medical Journal 2013; 14: 6

Parent Concrete Quality of Recycled Concrete Aggregates on Some Engineering Properties of Concrete

This paper aims to investigate some properties of recycled aggregates concrete (RAC) containing various amount of recycled concrete aggregates (RCA) supplied from different parent concrete strength. Three concretes with different strengths were made. After hardening, they were crushed and the obtained RCA were used to substitute 20%, 40% and 60% of coarse ordinary aggregates (COA) in concrete mix. The properties of these RCA according to their parent concrete strength were analyzed and their effects on the workability, compressive strength and shrinkage were quantified. Concrete workability and final shrinkage seem to be related to the equivalent water absorption of coarse recycled aggregates. An equivalent granular expression can be used in classical model to predict compressive strength according to the RCA content and its parent concrete strength.

Blueberry muffin syndrome

Le Blueberry Muffin Baby est un syndrome cutané rare observé en période néonatale. Il est caractérisé par des papulo-nodules disséminés inflammatoires traduisant des réactions d’hématopoïèse dermique. Plusieurs causes doivent être recherchées, notamment les infections congénitales, une hémolyse sévère et les pathologies tumorales. Nous rapportons l’observation d’un nouveau-né chez qui l’aspect d’un Blueberry muffin baby a conduit au diagnostic d’une leucémie aiguë myéloïde.Pan African Medical Journal 2012; 13:2

Parent Concrete Quality of Recycled Concrete Aggregates on Some Engineering Properties of Concrete

This paper aims to investigate some properties of recycled aggregates concrete (RAC) containing various amount of recycled concrete aggregates (RCA) supplied from different parent concrete strength. Three concretes with different strengths were made. After hardening, they were crushed and the obtained RCA were used to substitute 20%, 40% and 60% of coarse ordinary aggregates (COA) in concrete mix. The properties of these RCA according to their parent concrete strength were analyzed and their effects on the workability, compressive strength and shrinkage were quantified. Concrete workability and final shrinkage seem to be related to the equivalent water absorption of coarse recycled aggregates. An equivalent granular expression can be used in classical model to predict compressive strength according to the RCA content and its parent concrete strength.

Mentalization-based treatment in clinical high risk for psychosis: A rationale and clinical illustration

Developmental clinical research in recent years has highlighted the value treating psychotic disorders at the earliest stage to reduce long-term morbidity. It is now suggested that treatment during the clinical high risk states (CHR), preceding by 1 to 4 years the onset of psychotic disorders, may delay or prevent the onset of psychosis, and contribute to a more positive prognosis. In this article, we wish to provide a rationale and clinical illustration of mentalization-based treatment (MBT) as an indicated preventive treatment for CHR. We will first review the notion of high-risk for psychosis, providing a trans-theoretical developmental framework for conceptualizing the clinical progression from sub-clinical towards clinical psychotic states. Second, we address the commonalities and differences between the constructs of mentalization and metacognition, and discuss their relevance in preventive psychotherapeutic treatment for CHR. Thirdly, we provide a clinical illustration of MBT to emerging psychosis. Finally, we conclude by discussing the specific contributions of MBT approach in youths at CHR, and the necessary research for evaluating its relevance in the context of risk for developing psychosis