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Punta Arenas, Chile

University of Magallanes is a university in the southern Chilean city of Punta Arenas. It is part of the Chilean Traditional Universities. The University of Magallanes was established in 1981 during the neoliberal reforms of the Chile's military regime as the successor of Universidad Técnica del Estado's Punta Arenas section. Universidad Técnica del Estado had established the Punta Arenas section in 1961. The University of Magallanes have campuses in Punta Arenas and Puerto Natales as well as a university centre in Puerto Williams. University of Magallanes publishes the humanities and social science journal Magallania twice a year. Wikipedia.

Soto-Sanchez D.E.,University of Magallanes | Pena R.,University of Concepcion | Cardenas R.,University of Chile | Clare J.,University of Nottingham | Wheeler P.,University of Nottingham
IEEE Transactions on Industrial Electronics | Year: 2013

A novel frequency changing conversion scheme using three cascade multilevel converters in a Π topology is presented. The scheme resembles a direct frequency converter using the cascade converter in its simplest form (series strings of H-bridge modules equipped with a dc link capacitor) as the building block of the overall converter. This yields a highly modular implementation approach which may be attractive for large power applications such as intertie connections and variable speed drives. Frequency conversion takes place in a cascade converter which connects the input and output ports. Two other converters are placed, respectively, in parallel to the input, to remove unwanted current components from the input, and the output to regulate output voltage. Operation of this topology is explained and a scheme to control all the converters is developed, including control of converter currents, capacitor voltages, and output voltage. Experimental results, using a low-power prototype, confirm the foundations of the topology and verify its overall performance operating as a power supply at typical output frequencies (25 Hz, 16 2/3Hz and dc) while being fed from a 50-Hz system. Additionally, PowerSIM simulations demonstrate that the topology may be suitable for implementing high-performance, high-power ac drive systems using vector control techniques. © 2012 IEEE.

Pena R.,University of Concepcion | Cardenas R.,University of Chile | Reyes E.,University of Magallanes | Clare J.,University of Nottingham | Wheeler P.,University of Nottingham
IEEE Transactions on Industrial Electronics | Year: 2011

This paper presents a control strategy for a doubly fed induction generator (DFIG) using an indirect matrix converter, which consists of an input side matrix converter and an output side voltage source converter (VSC). The capability of the input converter to generate different "virtual dc link" voltage levels is exploited. The commutation of the VSI with reduced voltage is illustrated for operating points where the output voltage demand is low without any deterioration of the current control performance. The proposed method leads to a reduction in the commutation losses in the output converter and reduced common-mode voltage. For the input converter, soft switching commutation is obtained by synchronizing the input and output converter pulsewidth-modulation patterns. This modulation strategy is particularly applicable in DFIG applications because the required rotor voltage decreases when the DFIG speed is close to the synchronous speed. The complete control strategy is experimentally validated using a 2-kW rig. © 2011 IEEE.

Rozzi R.,University of North Texas | Rozzi R.,University of Magallanes
Environmental Ethics | Year: 2012

Biocultural homogenization involves three major drivers: (a) the physical barrier to everyday contact with biodiversity derived from the rapid growth of urban population, (b) the conceptual barrier derived from the omission in formal and non-formal education of native languages that contain a broad spectrum of traditional ecological knowledge and values, and (c) political barriers associated with the elimination or reduction of the teaching of ethics under the prevailing neoliberal economy governance since the 1960s. Biocultural ethics aims at overcoming these barriers by recovering the vital links between biological and cultural diversity, between the habits and the habitats of the inhabitants. These links are acknowledged by early Western philosophy, Amerindian traditional ecological knowledge, and contemporary ecological and evolutionary sciences, but have been lost in prevailing modern ethics. There is an overlooked diversity of forms of knowing and inhabiting regional ecosystems, each of them having diverse environmental and social consequences. A better understanding of the regionally diverse mosaics of ecosystems, languages, and cultures facilitates the distinction of specific causes and responsible agents of environmental problems, and the disclosure of sustainable practices, forms of ecological knowledge and values that offer already existing options to solve socio-ecological problems.

Vidal H.,University of Magallanes | Colle S.,Federal University of Santa Catarina
Applied Thermal Engineering | Year: 2010

This paper describes the hourly simulation and optimization of a thermally driven cooling cycle assisted by solar energy. The double stage solar ejector cooling cycle is modelled using the TRNSYS-EES simulation tool and the typical meteorological year file containing the weather data of Florianópolis, Brazil. The first stage is performed by a mechanical compression system with R134a as the working fluid, while the second stage is performed by a thermally driven ejector cycle with R141b. Flat plate collectors and an auxiliary energy burner provide heat to the ejector cycle. The thermo-economical optimization is carried out with respect to the intercooler temperature and the flat plate solar collector area, for given specific costs of the auxiliary energy and electric energy, the capital cost of the collectors, ejector cooler, and the capital cost of equivalent mechanical compression cooler. © 2009 Elsevier Ltd. All rights reserved.

Loaiza S.,University of Magallanes | Atalah E.,University of Chile
Public Health Nutrition | Year: 2013

Objective To determine the association of birth weight with obesity risk at first grade of high school in Chilean children after accounting for potential confounding factors. Design National non-concurrent cohort of newborns. Sociodemographic information, height, weight and anthropometric measurements at first grade of high school were analysed. Birth weight was classified as macrosomia (≥4000 g), by gestational age and by ponderal index. The relationship between birth weight and obesity at first grade of high school (BMI ≥ 95th percentile of the US Centers for Disease Control and Prevention's reference) was assessed using logistic regression models adjusted for sociodemographic information at delivery. Setting First grade of public high school of low and middle socio-economic status in the whole country (about 77 % of Chilean children in this age group). Subjects Newborns (n 119 070) and the same number of high-school students. Results A positive relationship of high ponderal index (OR = 1·86, 95 % CI 1·69, 2·03), birth weight ≥4000 g (OR = 1·66, 95 % CI 1·54, 1·78) and large for gestational age (OR = 1·69, 95 % CI 1·58, 1·81) with obesity at adolescence (P < 0·001) was found. Macrosomic children had a higher risk of being obese at first grade of high school after controlling for prenatal confounding variables (OR = 1·63, 95 % CI 1·52, 1·76; P < 0·001). Conclusions A direct relationship between high birth weight and obesity at first grade of high school was observed in this group of Chilean children. The results highlight the significance of birth weight as a simple tool to be used as an indicator of obesity risk for children by health-care providers. © The Authors 2012.

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