A Proposal for the Integration of the Energy Matrix from a Graph Theory Perspective

Brazil has stood out as a major producer of renewable energy in the world, despite advances in terms of its use, it is not yet a potential collaborative generator due to the inability of a bidirectional flow over the existing energy matrix, which has, in its extension, a strong limitation from the topological point of view, therefore, looking for computational models that operate within optimal solutions, supported by Graph Theory, is the objective of this work, making use of the Kruskal and Vertex Cover algorithms. to identify an alternative capable of producing a usable scenario under the implementation aspect and with a reduction of the costs under this expansion

Calcium fortification of roasted and ground coffee with different calcium salts

This study determined the calcium content and sensory attributes of roast and ground coffee fortified with calcium carbonate, calcium citrate malate, and calcium phosphate. The beverages made from fortified coffee powder were compared with a control (unfortified beverage). Two experts in coffee sensory testing analyzed six samples of coffee with the addition of different calcium salts; they assessed the aroma, color, and characteristic flavor of traditional coffee. The formulations containing calcium carbonate (A), calcium citrate malate (B), and calcium phosphate (C) were selected and used to verify the effect of using paper and polyester to filter infusions. Formulation B had the greatest purchase intent and presented the highest calcium content in the beverage, and it was considered rich in this mineral. The daily habit of drinking a cup of coffee (50 mL) has been popularized inBrazil; therefore, the addition of calcium citrate malate into traditional coffee powder can be an excellent calcium source and ensure the healthy intake of this macro mineral

Persistências e rupturas no estudo do Coronavírus após a epidemia da COVID-19

O presente artigo, partindo do conjunto de palavras-chave de mais de 500 artigos relacionados à família do coronavírus, com publicações ao longo de 20 anos (2002 – 2022) e a formação de redes semânticas, analisa tais redes em sua topologia e características, assim como o conjunto de análises sobre as centralidades de nós, com o objetivo de vislumbrar uma métrica que apontasse temas e autores que colaboraram no estudo dos coronavírus antes da pandemia, aqueles que vieram antes da pandemia, mas tiveram contribuição relevante ao longo da pandemia nos anos estudados e aqueles que se somaram nos pós start da pandemia. No geral, busca-se analisar as persistências e rupturas da comunidade acadêmica frente ao novo Sars-Cov-2.  Tal método se justifica como uma rota rápida e eficaz para filtrar bases teóricas e experimentais, pessoas e conhecimentos frente a um novo desafio, tal qual uma pandemia. Em linhas gerais, admite-se, neste trabalho, que palavras-chave são descritores importantes dos artigos publicados e, assim sendo, também cumprem um papel relevante como indicadores da agenda de pesquisa da comunidade de ciência. Percebe-se que as redes semânticas formadas por palavras-chave dos artigos selecionados mostraram aqui uma topologia com fortes características de uma rede mundo pequeno, o que evidencia uma forte ligação entre uma palavra-chave qualquer e sua vizinhança

Analysis of Hydrous Ethanol Price Competitiveness after the Implementation of the Fossil Fuel Import Price Parity Policy in Brazil

Competition is a relevant element in any open economy. Public policies are necessary to induce economic efficiency and to create conditions to preserve or stimulate a competitive environment. This paper aims to assess the competitiveness of hydrous ethanol price in a period of political, social and economic crises, in 15 Brazilian state capitals between the years 2012 and 2019. We compared the ethanol–gasoline price ratio behavior in two different periods, before and after the import parity price policy implemented by Petrobras in 2016. Mann–Whitney and Levene’s tests, two non-parametric statistical methods, were applied to verify significant changes between these periods. The implementation of changes in Petrobras’ pricing policy from 2016 onwards caused a statistically significant increase in the ratio coefficient of variation in two-thirds of the distribution market and more than the half of analyzed retail markets. Second, overall, the cities that showed statistically significant changes in the median and coefficient of variation in the distribution market price ratio were followed by the retail market. Our findings suggest that government interventions in the fuel and byproduct final selling prices to distributors negatively impact competition between companies that are part of the fuel distribution and retail chain, also affecting the sale of biofuels in Brazil and discouraging the initiatives to use renewable fuels to reduce the emission of pollutants

Generic dynamics for evolution groups and Co-semigroups on Hilbert spaces

Submitted by Izabela Soares ([email protected]) on 2019-09-18T12:41:14Z No. of bitstreams: 1 Tese_Moacir.pdf: 558137 bytes, checksum: 1113e1f912a5e94b4f6ff5fb60f8ef1b (MD5)Approved for entry into archive by Eliane Andrade ([email protected]) on 2019-10-01T12:09:51Z (GMT) No. of bitstreams: 1 Tese_Moacir.pdf: 558137 bytes, checksum: 1113e1f912a5e94b4f6ff5fb60f8ef1b (MD5)Approved for entry into archive by Eliane Andrade ([email protected]) on 2019-10-01T12:11:35Z (GMT) No. of bitstreams: 1 Tese_Moacir.pdf: 558137 bytes, checksum: 1113e1f912a5e94b4f6ff5fb60f8ef1b (MD5)Made available in DSpace on 2019-10-17T00:17:26Z (GMT). No. of bitstreams: 1 Tese_Moacir.pdf: 558137 bytes, checksum: 1113e1f912a5e94b4f6ff5fb60f8ef1b (MD5) Previous issue date: 2019-05-10CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorIn this thesis, we study the typical behaviour (from the topological viewpoint) of the decaying rates of the orbits of unitary evolution groups and 0-semigroups on Hilbert spaces. We have found that: (1) some dynamical quantities related to evolution groups have an oscillating behaviour between a polynomially rapid decay and an arbitrarily slow decay; (2) the decaying rates of each typical orbit, in Baire’s sense, of 0-semigroups which are stable but not exponentially stable depend on sequences of time going to infinity. The proofs are based on the relations between such decaying rates and some spectral properties of their respective generators.Nesta tese, estudamos o comportamento típico (do ponto de vista topológico) das taxas de decaimento das órbitas de grupos unitários de evolução e 0-semigrupos em espaços de Hilbert. Encontramos que: (1) algumas quantidades dinâmicas relacionadas aos grupos de evolução tem um comportamento oscilando entre um decaimento polinomialmente rápido e um decaimento arbitrariamente lento; (2) as taxas de decaimento de cada órbita típica, no sentido de Baire, de 0-semigrupos que são estáveis mas não exponencialmente estáveis dependem de sequências do tempo que vão para infinito. As provas são baseadas nas relações existentes entre essas taxas de decaimento e propriedades espectrais dos respectivos geradores

Dimensões fractais generalizadas e seu papel na dinâmica quântica

Exportado OPUSMade available in DSpace on 2019-08-11T14:14:18Z (GMT). No. of bitstreams: 1 dissertacao_moacir.pdf: 488860 bytes, checksum: cd714e9543698a1e804d9dc099902f98 (MD5) Previous issue date: 10Neste trabalho, apresentamos relações entre o grupo unitário de evolução gerado por um operador auto-adjunto definido em (...) e algumas propriedades fractais de suas respectivas medidas espectrais. Mais especificamente, apresentamos resultados que fornecem limitantes inferiores para os expoentes de transporte em termos das dimensões fractais generalizadas associadas às medidas espectrais do respectivo operador auto-adjunto. Para a situação particular de um operador de Schrödinger definido em (..), apresentamos limitantes inferiores para tais dimensões em termos das chamadas matrizes detransferência.In the present text we discuss some relations between the unitary evolution group generated by a self-adjoint operator defined in (...) and some fractal properties of its spectral measures. More precisely, we present some lower bounds for the transport exponents related to a self-adjoint operator in terms of the generalized fractal dimensions of itsspectral measures. In particular, for Schrödinger operators defined in (...),these lower bounds are presented in terms of transfer matrices