O uso do Geogebra como ferramenta para a construção de conceitos matemáticos: um primeiro estudo envolvendo Cadeias de Markov

Esse trabalho apresenta os resultados de uma sequência de atividadesrealizada com alunos de graduação em matemática e também com professores dematemática da região de Passo Fundo (RS). Através de uma metodologia de trabalhofundamentada na Engenharia Didática, a exploração de uma situação-problema inicialenvolvendo Cadeias de Markov1, conduziria os participantes em um processo deelaboração e verificação de hipóteses matemáticas. A análise das produções ocorre àluz da teoria da abstração reflexionante proposta por Piaget, onde através de passossucessivos os sujeitos elaboram, constroem e reconstroem conceitos de matemáticadurante a sequência de atividades. A utilização do objeto virtual apontou que aconstrução dos conceitos ocorre de forma gradual e é potencializada com o uso datecnologia

Comparison of temporal and spatial variation of periphytic algal community in two urban lakes in Umuarama-PR (Brazil)

Water resources are very important for all living organisms, and as being of vital importance need to be preserved. Thus, many water bodies are monitored as an essential strategy for identification of possible alterations over space and time. The analyses were performed in two different hydrological conditions, and water sample and rocks were collected in two different points at each lake. The results showed higher values of Ammoniacal Nitrogen in Aratimbó Lake, mainly during dry period (Ammoniacal Nitrogen = 4.2 mgL-1) at P1. However, P2 at Tucuruvi Lake presented higher concentration of Orthophosphate (2.24 mgL-1). Total Periphyton density also demonstrated variation among the different hydrological scenarios and lakes. The Highest density was of 385.30 10³ ind.cm-2at Aratimbó Lake and 180.43 10³ ind.cm-2at Tucuruvi Lake in rainy condition. Comparing the predominance of species, In Aratimbó Lake, Chlorophyceae class was predominant at P1, while Cyanophyceae class was predominant at P2. In dry period, Bacillarophyceae class was seen as the predominant class for both of lakes and for all sampling points. Differently from Aratimbó Lake, in Tucuruvi Lake Bacillarophyceae class was predominant in both of hydrological scenarios

Análise regressiva socioeconômica e ambiental para compreensão da organização sindical e atuação do poder público: estudo de caso do assentamento Paulo Fonteles – Mosqueiro, Belém –PA / Regressive socioeconomic and environmental analysis to understand the union organization and the role of the government: case study of the Paulo Fonteles settlement - Mosqueiro, Belém - PA

O objetivo do estudo foi compreender, através da metodologia SEA, qual é a influência da organização dos moradores do Assentamento Paulo Fonteles sobre as melhorias produtivas e sociais, bem como a força de reivindicação que a união dos assentados exerce sobre ações do poder público na melhoria da qualidade de vida desta população.  O levantamento ocorreu em uma unidade familiar em 18 de junho de 2019. Para a construção da dimensão de análise “organização sindical e atuação do poder público”, foram selecionadas características que poderiam atribuir informações pertinentes à dimensão estudada, tais como: participação em associação de produtores ou movimentos organizacionais, capacidade dos produtores de reivindicar direitos em instâncias decisórias, atuação do poder público, atuação dos provedores de serviços, organização dos moradores mediante da gestão dos recursos naturais e atuação dos moradores em atividades de produção agropecuárias. Para cada cara houve a classificação que variou de 01 a 05, sendo 01 (muito baixo) e 05 (muito alto), fazendo uma comparação entre os anos de 2006 e 2019. Identificou-se que no intervalo de tempo avaliado houve decréscimo nos atributos estudados, com exceção do atributo “participação do poder público”, que segundo a entrevistada, sempre foi insuficiente.  A partir da análise SEA, pode-se concluir que dentre todos os atributos presentes na dimensão “organização sindical e atuação do poder público”, o atributo “participação em associação de produtores ou movimentos organizacionais”, exerceu a maior influência na dinâmica da maioria dos resultados encontrados na dimensão pesquisada

Improved objective bayesian estimator for a PLP model hierarchically represented subject to competing risks under minimal repair regime

In this paper, we propose a hierarchical statistical model for a single repairable system subject to several failure modes (competing risks). The paper describes how complex engineered systems may be modelled hierarchically by use of Bayesian methods. It is also assumed that repairs are minimal and each failure mode has a power-law intensity. Our proposed model generalizes another one already presented in the literature and continues the study initiated by us in another published paper. Some properties of the new model are discussed. We conduct statistical inference under an objective Bayesian framework. A simulation study is carried out to investigate the efficiency of the proposed methods. Finally, our methodology is illustrated by two practical situations currently addressed in a project under development arising from a partnership between Petrobras and six research institutes

Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of $t\overline{t}$, $W+b\overline{b}$ and $W+c\overline{c}$ is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 $\pm$ 0.02 \mbox{fb}^{-1}. The $W$ bosons are reconstructed in the decays $W\rightarrow\ell\nu$, where $\ell$ denotes muon or electron, while the $b$ and $c$ quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

An embedding technique to determine ττ backgrounds in proton-proton collision data

An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

Peer reviewe

Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.