Going twice to the polls?: Optimality of two-stage voting procedures

A Masters Thesis, presented as part of the requirements for the award of a Research Masters Degree in Economics from NOVA – School of Business and Economics

Human activity recognition for an intelligent knee orthosis

Dissertação para obtenção do Grau de Mestre em Engenharia Biomédica

Direito da religião

This dissertation stands out the religious and social role of Christian religious minorities in Portuguese society, where the vast majority of the believers profess the Catholic faith. This work serves to demystify the widespread prejudice against minorities and clarify its place in the religious phenomenon in Portugal. We intend to define the concept of Religion, missing in the Portuguese legislation, framing it in Portuguese constitutional history, which allows us to evaluate the relations State/Catholic Church and State/religious minorities, since Liberalism. We attempt to measure how the legal system accepts the religious phenomenon and how to deal with religious diversity, according to the principle of religious freedom postulated in the Constitution of the Portuguese Republic. It is also our intention to relate the concepts of sect and religious minority, which tendentiously are misunderstood. In order to understand the underlying dynamics of religious minorities, we take the example of the Portuguese Evangelical Alliance, which we monitored closely throughout the investigation. We will give some space for a small analysis of the state and social discrimination experienced by the minorities. With this work we can conclude in general that Portugal, despite its weak religious diversity, has a good advance on the religious freedom. The Portuguese State has made a remarkable effort to cooperate with the churches, an effort that must be continued in order to fill some gaps found, particularly in the absence of legislation regarding the criminalization of religious discrimination and competence of the Committee on Religious Freedom in case of a possible complaint. We prove similarly that there is also a special attention to the Catholic Church in the composition of the Committee on Religious Freedom and the Committee Broadcast Time of Religious Confessions. In the end, we prove that the society is the major source of discrimination against minorities.

2D position system for a mobile robot in unstructured environments

Nowadays, several sensors and mechanisms are available to estimate a mobile robot trajectory and location with respect to its surroundings. Usually absolute positioning mechanisms are the most accurate, but they also are the most expensive ones, and require pre installed equipment in the environment. Therefore, a system capable of measuring its motion and location within the environment (relative positioning) has been a research goal since the beginning of autonomous vehicles. With the increasing of the computational performance, computer vision has become faster and, therefore, became possible to incorporate it in a mobile robot. In visual odometry feature based approaches, the model estimation requires absence of feature association outliers for an accurate motion. Outliers rejection is a delicate process considering there is always a trade-off between speed and reliability of the system. This dissertation proposes an indoor 2D position system using Visual Odometry. The mobile robot has a camera pointed to the ceiling, for image analysis. As requirements, the ceiling and the oor (where the robot moves) must be planes. In the literature, RANSAC is a widely used method for outlier rejection. However, it might be slow in critical circumstances. Therefore, it is proposed a new algorithm that accelerates RANSAC, maintaining its reliability. The algorithm, called FMBF, consists on comparing image texture patterns between pictures, preserving the most similar ones. There are several types of comparisons, with different computational cost and reliability. FMBF manages those comparisons in order to optimize the trade-off between speed and reliability.