Orbit based procedure for doublets of scalar fields and the emergence of triple kinks and other defects

In this work we offer an approach to enlarge the number of exactly solvable models with two real scalar fields in (1+1)D. We build some new two-field models, and obtain their exact orbits and exact or numerical field configurations. It is noteworthy that a model presenting triple-kinks and double-flat-top lumps is among those new models

Energy efficiency of transmit diversity systems under a realistic power consumption model

We compare the downlink energy efficiency of spatial diversity multiple transmit antenna schemes. We determine the minimum required transmit power for a given outage probability. Our analysis shows that antenna selection is in general the most energy efficient option as it requires a single radio-frequency chain. We also investigate the limiting distances up to which the antenna selection technique outperforms the transmit beamforming scheme for different numbers of transmit antennas

Agent-oriented Modeling for Collaborative Learning Environments: A Peer-to-Peer Helpdesk Case Study

In this paper, we present the analysis and modelling of Help&Learn, an agent-based peer-to-peer helpdesk system to support extra-class interactions among students and teachers. Help&Learn expands the student’s possibility of solving problems, getting involved in a cooperative learning experience that transcends the limits of classrooms. To model Help&Learn, we have used Agent-Object-Relationship Modeling Language (AORML), an UML extension for agent-oriented information systems modeling. The aim of this research is two-fold. On one hand, we aim at modeling the variety of roles and the complexity of their interactions and activities within the Help&Learn system. On the other hand, we aim at showing the expressive power and the modeling strengths of AORML

Poverty, Inequality and Social Policies in Brazil, 1995-2009

Since the mid-1990s, Brazil has undergone extensive reforms that have finally reversed the dismaying economic performance of the 1980s. In particular, poverty and inequality indicators have improved dramatically, especially since the late-2000s. This paper provides an overview of such recent trends and discusses the role played by four major government interventions: public education, the minimum wage law, Social Security pensions and Social Assistance transfers. Additionally, available data sets and methods for policy evaluation are also discussed. (?)Poverty, Inequality and Social Policies in Brazil, 1995-2009

Social Policies and the Fall in Inequality in Brazil: Achievements and Challenges

By the end of the first decade of the 21st century, the most usual international depiction of Brazil is that of a burgeoning, upcoming country. Although in many ways frankly exaggerated, this marks a stark contrast with a not-so-distant past. This turnaround has had a lot to do with favourable international circumstances, but it also owes a lot to extensive reforms that made possible something that was almost unprecedented in Brazil: pro-poor growth. (?)Social Policies and the Fall in Inequality in Brazil: Achievements and Challenges