Oposiçao política em Portugal nas vésperas da Restauraçao.

Sin resume

Relatório de Actividades do Laboratório de Acústica: biénio 2002-2003

O presente Relatório de Actividades do Laboratório de Acústica - LAfeup corresponde ao biénio 2002/2003. Apresenta-se a organização e enquadramento na FEUP, os recursos humanos e financeiros envolvidos, a investigação, a consultoria técnica e científica e a difusão de conhecimentos desenvolvida

The impact of implicit trading costs on trading venue competition

In the last 20 years, the U.S. equity markets structure has been changing drastically. The Securities and Exchange Commission (SEC), driven by numerous studies regarding market competition and economic efficiency, recognizing these two variables as having a positive correlation (Casu & Girardone, 2009; Porter, 1990), started to implement policies against market dominance. On August 29th, 2005, the Regulation National Markets System (Reg NMS) was released to harmonize regulation for equity trading services within the U.S., increasing competition and consumer protection in the trading industry services. Using panel data regarding order execution from September 2016 to December 2016. This research attempted to evaluate the effectiveness of Reg NMS regarding trading venues competition using a multinomial logit demand model for differentiated products with dummy variables to capture a non-observable variable. The results suggest that, even though, implicit trading costs, are essential to estimate the trading demand still exists market dominance in the U.S. trading venues, resulting in unusually inelastic price elasticities

Feature-based underwater localization using an imaging sonar

The ability of an AUV to locate itself in an environment as well as to detect relevant environmental features is of key importance for navigation success. Sonars are one the most common sensing devices for underwater localization and mapping, being used to detect and identify underwater structural features. This study explores the processing and analysis of acoustic images, through the data acquired by a mechanical scanning imaging sonar, in order to extract relevant environmental features that enable location estimation. For this purpose, the performances of different state-of-the art feature extraction algorithms were evaluated. Furthermore, an improvement to the feature matching step is proposed, in order to adapt this procedure to the characteristics of acoustic images. The extracted features are then used to feed a location estimator composed of a Simultaneous Localization and Mapping algorithm implementing an Extended Kalman Filter. Several tests were performed in a structured environment and the results of the feature extraction process and localization are presented

Coalition based approach for shop floor agility – a multiagent approach

Dissertation submitted for a PhD degree in Electrical Engineering, speciality of Robotics and Integrated Manufacturing from the Universidade Nova de Lisboa, Faculdade de Ciências e TecnologiaThis thesis addresses the problem of shop floor agility. In order to cope with the disturbances and uncertainties that characterise the current business scenarios faced by manufacturing companies, the capability of their shop floors needs to be improved quickly, such that these shop floors may be adapted, changed or become easily modifiable (shop floor reengineering). One of the critical elements in any shop floor reengineering process is the way the control/supervision architecture is changed or modified to accommodate for the new processes and equipment. This thesis, therefore, proposes an architecture to support the fast adaptation or changes in the control/supervision architecture. This architecture postulates that manufacturing systems are no more than compositions of modularised manufacturing components whose interactions when aggregated are governed by contractual mechanisms that favour configuration over reprogramming. A multiagent based reference architecture called Coalition Based Approach for Shop floor Agility – CoBASA, was created to support fast adaptation and changes of shop floor control architectures with minimal effort. The coalitions are composed of agentified manufacturing components (modules), whose relationships within the coalitions are governed by contracts that are configured whenever a coalition is established. Creating and changing a coalition do not involve programming effort because it only requires changes to the contract that regulates it

Note on the integer geometry of bitwise XOR

AbstractWe consider the set N of non-negative integers together with a distance d defined as follows: given two integers x,y∈N, d(x,y) is, in binary notation, the result of performing, digit by digit, the “XOR” operation on (the binary notations of) x and y. Dawson, in Combinatorial Mathematics VIII, Geelong, 1980, Lecture Notes in Mathematics, 884 (1981) 136, considers this geometry and suggests the following construction: given k different integers x1,…,xk∈N, let Vi be the set of integers closer to xi than to any xj with j≠i, for i,j=1,…,k. Let V=(V1,…,Vk) and X=(x1,…,xk). V is a partition of {0,1,…,2n−1} which, in general, does not determine X.In this paper, we characterize the convex sets of this geometry: they are exactly the line segments. Given X and the partition V determined by X, we also characterize in easy terms the ordered sets Y=(y1,…,yk) that determine the same partition V. This, in particular, extends one of the main results of Combinatorial Mathematics VIII, Geelong, 1980, Lecture Notes in Mathematics, 884 (1981) 136