This work presents a new and useful method to dimension wind turbines and control systems and to optimize their mechanical design. This method allows determining the principal curves for characterizing a small capacity wind turbine designed with a Permanent Magnet Synchronous Generator (PMSG). For the wind turbine characterization it was considered the losses in the process of energy transformation in the wind rotor, electric generator and in the bridge rectifier. The equivalent electric model of the synchronous generator was used to determine the electric parameter performance. The work of the wind rotor was considered in its maximum power curve and the PMSG performance in the linear region of its magnetization curve. This leads to develop a new methodology for the complete wind turbine characterization from the nominal parameters of the wind rotor and the electric generator. This method also allows obtaining the power curves and the parameters of voltage, current and efficiency around the wind speed domain and angular speed in the wind rotor. The method was tested for small-capacity wind turbine (1 kW and 10 kW) performances and the numerical and experimental results are described.

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Chicanxs Unidxs de Orange County (CU) is a community organisation in Southern California. Founded in 2006, CU is small, multigenerational and multi-ethnic. Its organising has focused predominantly on building community power by focusing on local politics, abusive policing and the gentrification of Chicanx neighbourhoods. This article presents an evidence-based narrative of several CU campaigns (primarily between 2008 and 2016). CU’s tactical aggressiveness and strategic pragmatism forced significant changes to ‘civil gang injunctions’ in California. For decades, California law enforcement has used such injunctions to suppress a generation of young people of colour as ‘gang members’. Minors and adults have been prohibited indefinitely from engaging in otherwise legal activities without due process. CU’s emphasis on the longevity of institutionalised and societal racism, rooted in the colonial conquest, resembles arguments associated with critical race theory (CRT) – though CU was not inspired by CRT. CU’s praxis resembles practices of critical pedagogy – though it was not directly modelled on it either. Rather, we argue that CU’s praxis is embedded in the members’ lived experience and study of the local history of racism, community and social movements. All five of this article’s authors were members of CU and were involved in the organising described in this article. The authors wrote this at the request of the CU membership, and it has been discussed and revised by the full membership.

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An investigation of the pigments used by the Dutch and Flemish masters from the brothers Van Eyck to the middle of the 19th century. London: G. Bell & Sons. 1929. 121 p. 34 Para ver más sobre las falsificaciones de obras de Johannes Vermeer hechas por Han van Meegeren: http://www.essentialvermeer.com/misc/van_meegeren.html#.VRgrdijURD0 119 PAÑUELAS I REIXACH Lluís. op. cit. (nota 115). p. 144.