Search results for "Condition"
showing 10 items of 2530 documents
Autoencoders and Data Fusion Based Hybrid Health Indicator for Detecting Bearing and Stator Winding Faults in Electric Motors
2018
The main objective of a condition monitoring programs is to track the health status of critical components of a machine. In this paper, a hybrid health indicator is proposed to monitor the health status of bearings and stator winding of a motor. The proposed method is based on a feature learning from deep autoencoders and data fusion. The features can be learned by autoencoders using individual current and vibration signals, and then learning features are fused to make final health indicators. The experimental data from a permanent magnet synchronous motor is used to validate the proposed method. Promising results in detecting faults and severities of the stator and bearing faults at differ…
A model of a linear synchronous motor based on distribution theory
2012
The fundamental idea of this paper is to use the distribution theory to analyze linear machines in order to include in the mathematical model both ideal and non ideal features. This paper shows how distribution theory can be used to establish a mathematical model able to describe both the ordinary working condition of a Linear Synchronous Motor (LSM) as well the role of the unavoidable irregularities and non ideal features.
A Two-Stage Fault Detection and Classification Scheme for Electrical Pitch Drives in Offshore Wind Farms Using Support Vector Machine
2019
Pitch systems are one of the components with the most frequent failure in wind turbines. This paper presents a two-stage fault detection and classification scheme for electric motor drives in wind turbine pitch systems. The presented approach is suitable for application in offshore wind farms with electric pitch systems driven by induction motors as well as permanent magnet synchronous motors. The adopted strategy utilizes three-phase motor current sensing at the pitch drives for fault detection and only when a fault condition is detected at this stage, features extracted from the current signals are transmitted to a support vector machine classifier located centrally to the wind farm. The …
A RADIATION CONDITION FOR UNIQUENESS IN A WAVE PROPAGATION PROBLEM FOR 2-D OPEN WAVEGUIDES
2009
We study the uniqueness of solutions of Helmholtz equation for a problem that concerns wave propagation in waveguides. The classical radiation condition does not apply to our problem because the inhomogeneity of the index of refraction extends to infinity in one direction. Also, because of the presence of a waveguide, some waves propagate in one direction with different propagation constants and without decaying in amplitude. Our main result provides an explicit condition for uniqueness which takes into account the physically significant components, corresponding to guided and non-guided waves; this condition reduces to the classical Sommerfeld-Rellich condition in the relevant cases. Final…
Social Housing Conditions Modulate the Long-Lasting Increase in Cocaine Reward Induced by Intermittent Social Defeat
2019
Social defeat is considered the most representative animal model for studying the consequences of social stress. Intermittent social defeat (ISD) has proved to enhance the response to cocaine hedonic properties. In the present research, we evaluated if different social housing conditions, as housing with a familiar conspecific or with a female, exert a protective effect modulating the negative consequences of ISD as the increased sensitivity to cocaine and the induction of anxiety-like behavior. To achieve this objective, non-stressed or ISD OF1 male mice were divided into five different experimental groups according to their social environment: standard housing (four adult males per cage);…
Ecological Indicator Values of Europe (EIVE) 1.0: A Powerful Open-Access Tool for Vegetation Scientists
2016
International audience; Background: Ecological indicator values (EIVs) have a long tradition in vegetation ecological research in Europe. EIVs characterise the ecological optimum of species along major environmental gradients using ordinal scales. Calculating mean indicator values per plot is an effective way of bioindication. Following first systems in Russia and Central Europe, about two dozen EIV systems have been published for various parts of Europe.Aims: As there was no EIV system available at European scale that could be used for broad- scale analyses, e.g. in the context of the European Vegetation Archive (EVA), we develop such a system for the first time for the vascular plants of …
Form-perturbation theory for higher-order elliptic operators and systems by singular potentials
2020
We give a form-perturbation theory by singular potentials for scalar elliptic operators onL2(Rd)of order 2mwith Hölder continuous coefficients. The form-bounds are obtained from anL1functional analytic approach which takes advantage of both the existence ofm-gaussian kernel estimates and the holomorphy of the semigroup inL1(Rd).We also explore the (local) Kato class potentials in terms of (local) weak compactness properties. Finally, we extend the results to elliptic systems and singular matrix potentials.This article is part of the theme issue ‘Semigroup applications everywhere’.
Hormonal and embryonic regulation of chemokines IL-8, MCP-1 and RANTES in the human endometrium during the window of implantation.
2002
Chemokines are a family of small polypeptides which specialize in the attraction of leukocytes. The presence of specific leukocyte subsets at the implantation site is an important element of the complex, and not completely understood, process of embryonic implantation. This report includes the investigation of the in-vivo immunolocalization and hormonal regulation of interleukin (IL)-8, monocyte chemotactic protein (MCP)-1 and RANTES (regulated upon activation normal T-cell expressed and secreted) in the human endometrium during hormone replacement therapy cycles for oocyte recipients in an IVF programme. In addition, we have analysed the embryonic regulation of these endometrial epithelial…
Inmigración, servicios públicos e integración social
2007
La configuración de nuestras sociedades como espacios de multiculturalidad ha motivado que la integración de la diversidad se convierta en uno de los mayores retos que afrontamos en la actualidad. La inclusión social de las personas inmigrantes en las sociedades de recepción se ve obstaculizada por las dificultades existentes en lo que refiere al reconocimiento de los derechos sociales. Con este artículo tratamos de hacer una aproximación a las condiciones en las que se produce el acceso de las personas inmigrantes a los recursos públicos, con especial atención a los servicios sanitarios.
Baisse soutenue de l'embauche des jeunes
2014
En Bourgogne, près de 8 300 jeunes ont quitté les classes terminales professionnelles et technologiques du lycée et de l'apprentissage en juin 2012. Sept mois plus tard, 53 pour cent des garçons et 46 pour cent des filles ont trouvé un emploi non aidé. Les effets de la crise perdurent : en 2013 l'économie régionale a perdu 4 200 emplois salariés. Cette dégradation induit une augmentation du chômage des jeunes, quel que soit le mode de formation. Dans un contexte marqué aussi par la réforme de la voie professionnelle, la hiérarchie des diplômes n'est toutefois pas remise en cause. Un niveau d'études plus élevé demeure un atout sur le marché du travail en termes d'accès à l'emploi et de condi…