Integration of control loops in coupled field circuit model to study magnetic devices supplied by power electronic converter and their control

In this paper, we present a method to take into account the feedback control in software developed from coupled field circuit models. The implementation of control loops is done in a software which is able to simulate electromagnetic devices associated with power electronic circuits having a time dependent topology. The control strategy is implemented in a discrete‐time version and can manage all controllable electronic switches by means of different electric or magnetic quantities calculated during the simulation (flux, currents, voltages, …). Electrical systems involving magnetic devices, power electronic converters and their control devices can be simulated in presence of phenomena such as eddy currents or saturation of the magnetic materials

Synthesis and modelling of an electrostatic induction motor

This paper deals with a new way of synthesis and modelling of electrostatic induction micromotors by means of duality rules from the magnetic induction machine. An electromechanical model based on this method is given. Then, a computational procedure based on a general lumped parameter model and an electric field calculation code, has been developed so as to simulate the dynamic working of these actuators. A comparison is made between the computation results and the model results. Satisfactory agreement between theory and simulation is obtained in most respect

Herlies – Le Clos de l’Abbaye, rue de l’Egalité

Date de l'opération : 1988 (SU) Inventeur(s) : Hoogardie Yvan Consécutivement à une surveillance d’un chantier de construction d’un lotissement, un certain nombre de structures appartenant aux époques gallo-romaine, mérovingienne et carolingienne ont pu être fouillées dans les tranchées de fondation des futures constructions. Il s’agit de vastes fosses interprétées comme des fosses de récupération d’argile et utilisées par la suite comme dépotoirs. Deux d’entre elles pourraient appartenir à ..

In vitro assessment of skin sensitization, irritability and toxicity of bacteriocins and reuterin for possible topical applications

Bacteriocins and reuterin are promising antimicrobials for application in food, veterinary, and medical sectors. In the light of their high potential for application in hand sanitizer, we investigated the skin toxicity of reuterin, microcin J25, pediocin PA-1, bactofencin A, and nisin Z in vitro using neutral red and LDH release assays on NHEK cells. We determined their skin sensitization potential using the human cell line activation test (h-CLAT). Their skin irritation potential was measured on human epidermal model EpiDerm™. We showed that the viability and membrane integrity of NHEK cells remained unaltered after exposure to bacteriocins and reuterin at concentrations up to 400 µg/mL and 80 mg/mL, respectively. Furthermore, microcin J25 and reuterin showed no skin sensitization at concentrations up to 100 µg/mL and 40 mg/mL, respectively, while pediocin PA-1, bactofencin A, and nisin Z caused sensitization at concentrations higher than 100 µg/mL. Tissue viability was unafected in presence of bacteriocins and reuterin at concentrations up to 200 µg/mL and 40 mg/ mL, respectively, which was confrmed by measuring cytokine IL-1α and IL-8 levels and by histological analysis. In conclusion, the current study provides scientifc evidence that some bacteriocins and reuterin, could be safely applied topically as sanitizers at recommended concentration

Une méthode générale pour modé1iser les convertisseurs statiques associés à des dispositifs magnétiques

In this paper a general method for modelling power electronics circuits associated with electromagnetic devices is presented. This model is based on the simultaneous resolution of the circuit equations and the field equations in electromagnetic devices and on a general solution for taking into account the switching of semiconductors. This method allows to consider phenomena such as eddy currents and saturation of magnetic materials in the electromagnetic devices associated with static converters. Dans cet article, nous présentons une méthode générale pour simuler les ensembles constitués de convertisseurs statiques associés à des structures magnétiques. Cette solution est basée sur la résolution simultanée des équations de type circuit du convertisseur couplées aux équations du champ dans la structure magnétique et sur une méthode générale pour gérer l'état des interrupteurs du circuit. Il est alors possible de considérer des phénomènes tels que les courants de Foucault ou la saturation des matériaux dans des structures associées à des convertisseurs

An original and natural method of coupling electromagnetic field equations with circuit equations put in a state form.

In this paper a general method of coupling static converters with electromagnetic devices is presented. This method is based on the simultaneous solution of the converter equations and the field equation in the electromagnetic devices. The equations are established in automatic way: the circuit equations are put in a state form and the field equations are discretized using FEM. An original way of linking the two systems of equations is proposed

A 2D Finite Element Formulation for the Study of the High Frequency Behaviour of Wound Components

When the frequency of power converters increases, the wound components like inductors or transformers can no longer be supposed ideal. In this paper a formulation using 2D finite elements is presented for studying the high frequency coupled magnetic and electric field problem (eddy currents, proximity effects and stray capacitance). This formulation is based on a particular division of the 3D spatial domain which enables a 2D calculation

Gastrointestinal stability and cytotoxicity of bacteriocins from gram-positive and gram-negative bacteria : a comparative in vitro study

Bacteriocins are receiving increased attention as potent candidates in food preservation and medicine. Although the inhibitory activity of bacteriocins has been studied widely, little is known about their gastrointestinal stability and toxicity toward normal human cell lines. The aim of this study was to evaluate the gastrointestinal stability and activity of microcin J25, pediocin PA-1, bactofencin A and nisin using in vitro models. In addition cytotoxicity and hemolytic activity of these bacteriocins were investigated on human epithelial colorectal adenocarcinoma cells (Caco-2) and rat erythrocytes, respectively. Pediocin PA-1, bactofencin A, and nisin were observed to lose their stability while passing through the gastrointestinal tract, while microcin J25 is only partially degraded. Besides, selected bacteriocins were not toxic to Caco-2 cells, and integrity of cell membrane was observed to remain unaffected in presence of these bacteriocins at concentrations up to 400 µg/mL. In hemolysis study, pediocin PA-1, bactofencin A, and nisin were observed to lyse rat erythrocytes at concentrations higher than 50 µg/mL, while microcin J25 showed no effect on these cells. According to data indicating gastrointestinal degradation and the absence of toxicity of pediocin PA-1, bactofencin A, and microcin J25 they could potentially be used in food or clinical applications

Semantic Deployment of Services in Pervasive Environments

International audiencePervasive devices, such as mobile phones or personal gateways, allows more and more to execute personal services and not only legacy services. This opportunity raises the challenge of deploying heterogeneous services non-previously considered in the environment. In this paper, we present an architecture for the semantic deployment of services in a pervasive environment. This architecture, based on a middleware distributed on each device, specially includes a Deployment Service interacting discovery and interoperability middleware services. This Deployment Service takes into account the semantic description of services and the semantic description of deployment itself to apply a semantically and timely local deployment strategy