This paper presents the simulation results of a grid-connected wind driven doubly fed induction machine (DFIM) together with some real machine performance results. The modeling of the machine considers operating conditions below and above synchronous speed, which are actually achieved by means of a double-sided PWM converter joining the machine rotor to the grid. In order to decouple the active and reactive powers generated by the machine, stator-flux-oriented vector control is applied. The wind generator mathematical model developed in this paper is used to show how such a control strategy offers the possibility of controlling the power factor of the energy to be generated. Index Terms-Doubly fed induction machine, power converter, power factor, vector control, wind power generation. I. NOMENCLATURE Stator side power factor. Wind turbine net power factor. Grid frequency. Stator magnetising current space phasor modulus. , Direct-and quadrature-axis stator magnetising current components respectively, expressed in the stationary reference frame. Rotor current space phasor modulus. , Direct-and quadrature-axis rotor current components respectively, expressed in the stationary reference frame. , Direct-and quadrature-axis rotor current components respectively, expressed in the stator-flux-oriented reference frame. , Reference values of the rotor current and components, respectively. , Direct-and quadrature-axis rotor current components respectively, expressed in the rotor natural reference frame. , Direct-and quadrature-axis stator current components respectively, expressed in the stationary reference frame.

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Respondents residing in more rural areas were disadvantaged in terms of cognitive functioning compared with those residing in more urban areas. Poorer cognitive functioning in late life may be the result of historical educational disadvantage in rural areas or selection through migration from rural to urban regions for employment.

Disparities in cognitive life expectancies indicate that intervention strategies should target the specific needs of minority and immigrant older adults with dementia. Given that education is a strong predictor of cognitive health, improving access to the social and economic resources that delay dementia onset is key to improving the well-being of diverse older adults.

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Indoor air pollution may be an important factor for the cognitive health of older Mexican adults. Public health efforts should continue to develop interventions to reduce exposure to indoor air pollution in rural Mexico.

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