Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-08-28T12:21:13Z No. of bitstreams: 1 2017 - Victor dos Santos Ponciano.pdf: 551672 bytes, checksum: c01424f760ef08254a63d236b62f72c5 (MD5) / Made available in DSpace on 2018-08-28T12:21:15Z (GMT). No. of bitstreams: 1 2017 - Victor dos Santos Ponciano.pdf: 551672 bytes, checksum: c01424f760ef08254a63d236b62f72c5 (MD5) Previous issue date: 2017-02-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / In 1946, Heider developed Signal Graph Theory with the purpose of describing the emotional relationships between people pertaining to the same social group. In this work, we study graph partitioning problems associated with structural balance. These problems are known in the computer science literature as partition correlation problems: correlation clustering (CC) and a relaxed version (RCC). The solution of CC and RCC problems has been previously used in the literature as a tool for the evaluation of structural balance in a social network. The aim of this work is to apply the solution of these problems in the detection of corruption in public contracts. We describe integer linear programming formulations from the literature for these problems. We also discuss a probabilistic model for Structural balance and the solution of these problems applied to the detection of cases of corruption existing in public bids. / Em 1946, Heider desenvolveu a Teoria de Grafos de Sinais a fim de descrever as rela??es emocionais entre as pessoas pertencentes ao mesmo grupo social. Neste trabalho, estudamos problemas de particionamento de grafo associados com equil?brio estrutural, que na literatura de Ci?ncia da Computa??o s?o conhecidos como problemas de correla??o de parti??es ou, em ingl?s, correlation clustering (CC), al?m de uma vers?o relaxada (RCC). As solu??es dos problemas CC e RCC foram anteriormente utilizadas na literatura como ferramentas para a avalia??o de equil?brio estrutural numa rede social. O objetivo deste trabalho ? aplicar as solu??es destes problemas na detec??o de corrup??o em contratos p?blicos. Para esse fim, s?o utilizadas formula??es de programa??o linear inteira existentes na literatura para estes problemas. Al?m disso, ? discutido tamb?m um modelo probabil?stico para o Equil?brio Estrutural e as solu??es destes problemas s?o aplicadas ? detec??o de casos de corrup??es existentes em licita??es p?blicas.

In my graduation thesis I first of all shortly mentioned frequency–selection filters and their utilisations. However, the base point of this project was to acquaint with different types of signal flow diagrams with whom I should design and analyse frequency-selection filtres with conventional and also innovative active components. As the first I created signal flow diagrams for both voltage and current conveyors. These modern active components are well known today and enable the construction of circuits with better properties than circuits with traditional differentiating amplifiers with voltage feedback. Thereinafter I made signal flow diagrams for OTA component. Transconductancal amplifiers are well known active components used in various areas of analog signal processing. OTA amplifier is in fact the current source controlled by voltage difference, which is characterised by gm transconductance. Ulterior components were IOZ and IZN models of voltage amplifier with voltage gain A. The last component was COA amplifier. It is a current operational amplifier. COA model is fully dual component to VOA, which is classical voltage amplifier. In my project I used filters with two OTA components. This filter offers functions like low-pass filter, band-pass filter, high-pass filter, band-stop filter and two-phase network. Following this I used circuits with two GCC conveyors. These offer band-pass filter, low-pass filter, high-pass filter, band-stop filter and two-phase network. Ultimately I designed filters with COA components, which offer three transmission functions simultaneously (DP, PP and HP). Analysis of these filters was made with a help of PSpice computer programme.