Participación de los actores socio-laborales en los sistemas nacionales de capacitación y formación técnica profesional (SNCFP) en América Latina

Incluye bibliografía

O envelhecimento da população e a economia geracional: principais resultados

Incluye bibliografía

Regulación del mercado de trabajo en uruguay: cambios recientes. La visión de los actores y la polémica sobre el sistema de relaciones laborales

Incluye Bibliografía

Avaliação das principais t́cnicas para obtenção de MPPT de paińis fotovoltaicos

Electrical energy from photovoltaic panels (PV) has became an increasing viable alternative because of the great concern for environmental preservation and the possibility of the reduction of the conventional fuels, and this natural energy source is free, abundant and clean. In addition, Brazil is a privileged country because of the high levels of irradiation throughout its territory all over the year. Thus the exploitation of the energy from PV is one of the best alternatives to overcome the supply electrical energy issues. However, nowadays the energy conversion efficiency is low and the initial costs are high for these energy systems. Therefore, in order to increase the efficiency of these systems the extraction of the maximum power point (MPP) from PV is extremely necessary, and it is done using the maximum power point tracking (MPPT) techniques. The MPP of the PV varies non linearly with the environmental conditions and several MPPT techniques are available in literature, and this paper presents a careful comparison among the most usual techniques, doing meaningful comparisons with respect to the amount of energy extracted, PV voltage ripple, dynamic response and use of sensors, considering that the models are implemented via MatLab/Simulink®. © 2010 IEEE.

Utilização de componentes principais para analisar o comportamento do cafeeiro a pleno sol e sombreado

The aim of this work is to describe the behavior of coffee (Coffea arabica L.) grown for nine years under organic management systems in full sun and shaded by banana trees (Musa sp.) and Erythrina verna Vell., in Valença, RJ. We performed a joint evaluation of vegetative characteristics, nutritional content and yield, with the aid of a principal component analysis. Twelve treatments were arranged in a randomized block design with four replications in a split plot. The plots evaluated farming systems in full sun and shade, and the subplots consisted of the following varieties of coffee: Tupi IAC 1669-33, MG 6851, IAC 3282 Icatu, Catucaí 2SL, Obatã IAC 1669-20; lineage IAC IAC 144. After five years we assessed the following variables, height, stem and canopy diameter, leaf area, number of branches, number of nodes per branch, number of leaves present, the distance between nodes, the percentage of green,ripe and dried fruit, number of dead plants, number of plants with death of the apical bud, coffee yield, and foliar concentrations of N, P, K, Ca and Mg. A multivariate analysis efficiently discriminates the variables in full sun and shaded cropping systems. Shading increases the percentage of green fruit, leaf area, height, diameter, distance between nodes, number of leaves on the branches, number of branches and leaf N content, but does not reduce the level of productivity when the shade is adequate.

Cambios sociales, actores y acción colectiva en América Latina

Incluye Bibliografía

Los programas de alivio a la pobreza Puente y Oportunidades: una mirada desde los actores

Incluye Bibliografía

De la evanescencia a la mira: el cuidado como eje de políticas y de actores en América Latina

Incluye Bibliografía

Globalización, actores sociales y democracia en América Latina

Incluye Bibliografía

Actores politicos y politicas de poblacion en un sistema democratico

Incluye Bibliografía

Unidades de analisis y los actores sociales del proceso de planificacion

Incluye Bibliografía

Las transformaciones en el pensamiento regionalista latinoamericano: escenas, discursos y actores

Incluye Bibliografía