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This paper describes an algebraic model for predicting the air flow-rate in the cooling system of an open self-ventilated machine. The method is easily applicable to any type of air-cooled electrical machine. The air flow-rates in different areas of the machine as well as the head losses of the hydraulic system were obtained, and the results were compared with a more detailed model developed with Computational Fluid Dynamic (CFD) techniques. Moreover, a sensitivity analysis was carried out in order to compare the different topologies of the machine studied. [ABSTRACT FROM AUTHOR]

In this paper, an analytical method to obtain the magnetic flwc in the air gap and the flux densities in surface mounted permanent magnet synchronous machines is described. The particularity of the method, which is based on the magnetic lumped parameter circuit approach, is that it is capable of predicting the magnetic decrease in the air gap due to the cross coupling between the d-axis and the q-axis (cross-magnetizing effect), shifting the angle of the magnetic axis. Moreover, the presented method can also evaluate the local flwc density level at the sides of the pole magnets, which is very useful for preventing local magnet demagnetization at load conditions. The methodology is compared with Finite Element Method based simulations, with very good results. [ABSTRACT FROM AUTHOR]

This paper presents an analytical method to compute the magnetic flux distribution in spoke interior permanent-magnet (IPM) machines with non-magnetic shaft from no-load to short-circuit conditions. Despite non-magnetic shaft gets significant reduction of the PM leakage flux, this cannot be neglected to calculate correct flux distribution; thus, shaft leakage flux is analyzed and modelled. Moreover, as the demagnetization characteristic of the machine depends on the magnetic circuit, simple mathematical equations to estimate the demagnetization level of the magnets are also given. Based on this approach, protection against demagnetization due to short-circuit current and maximum field-weakening level achievable are easily estimated. The presented formulation and methods are used to optimize the rotor of an IPM machine in order to maximize the electromagnetic torque (30% higher), minimize the amount of PM material, and protect PMs against demagnetization under field-weakening and short-circuit conditions. Analytical results are compared with finite-element software, showing errors lower than 4% in the no-load magnetic circuit and lower than 12% at short-circuit conditions. Presented formulation and methods have very low computation time, so the design process time of spoke IPM machines is significantly reduced. The proposed analytical approach is also applicable to other PM machines. [ABSTRACT FROM AUTHOR]

Serial assessment of ventricular function by means of radionuclide angiography was performed in 50 patients with malignant neoplasms who received either 4'-epidoxorubicin or mitoxantrone for longer than 3 months. In 9 of 30 patients given 4'-epidoxorubicin, a decrease of greater than or equal to 10% in the left ventricular ejection fraction (LVEF) was documented at doses of 143-1200 mg/m2. Two patients developed clinical signs of cardiotoxicity at a dose of greater than 1000 mg/m2. In 6 of 20 patients given mitoxantrone a decrease of greater than or equal to 10% in the LVEF occurred at doses of 26-98 mg/m2. [ABSTRACT FROM AUTHOR]

Objective. Analyze the distribution infrastructure potable water and health in the state of Nuevo Leon. Materials and methods. To this end, the territorial distribution of the company is analyzed using a geographic information system (GIS) in order to demonstrate the existing territorial gap in the formulation of public policy in the hydraulic and health sectors. Results. We show that municipalities with greater social marginalization (no running water or access to health services) tend to have the worst health outcomes. Conclusion. It is located in Nuevo Leon there is an unequal distribution of material and human resources in the drinking water and health, as there is a high concentration of these resources in the metropolitan area and the consequent neglect of the municipalities of the periphery. Objetivo. Analizar la distribución de la infraestructura de los sistemas de agua potable y de salud en el estado de Nuevo León. Materiales y métodos. Para tal fin, se analiza la distribución territorial de la entidad mediante un sistema de información geográfica (SIG) con el objeto de demostrar la carencia territorial existente en la formulación de las políticas públicas en los sectores hidráulico y de la salud. Resultados. Se demuestra que los municipios con mayor marginación social (sin agua potable ni acceso a servicios de salud) tienden a presentar los peores resultados sanitarios. Conclusión. Se encuentra que en Nuevo León existe una distribución desigual de los recursos materiales y humanos en los sistemas de agua potable y de salud, ya que existe una alta concentración de estos recursos en el área metropolitana y el consecuente descuido de los municipios de la periferia.