struc2vec: Learning Node Representations from Structural Identity

Structural identity is a concept of symmetry in which network nodes are identified according to the network structure and their relationship to other nodes. Structural identity has been studied in theory and practice over the past decades, but only recently has it been addressed with representational learning techniques. This work presents struc2vec, a novel and flexible framework for learning latent representations for the structural identity of nodes. struc2vec uses a hierarchy to measure node similarity at different scales, and constructs a multilayer graph to encode structural similarities and generate structural context for nodes. Numerical experiments indicate that state-of-the-art techniques for learning node representations fail in capturing stronger notions of structural identity, while struc2vec exhibits much superior performance in this task, as it overcomes limitations of prior approaches. As a consequence, numerical experiments indicate that struc2vec improves performance on classification tasks that depend more on structural identity.Comment: 10 pages, KDD2017, Research Trac

Does earnings management influence dividend policies? An approach with unlisted firms

The goal of this paper is to analyze whether the firms’ dividend policy is influenced by the existence of earnings management practices, particularly under different ownership contexts. In the paper, three well-known discretionary accruals methodologies are applied to measure earnings management. The empirical study relies on an innovative set of 4,258 unlisted private companies, representing a panel of around 20 thousand observations distributed over the period 2013-2017. The study is focused only in one European country to avoid different institutional and country characteristics that could bias the findings. Our firs result reveals a positive statistically significant relationship between the earnings management and dividend policy, meaning that private non-listed companies managing earnings are more likely to distribute a higher level of dividends. However, a deeper analysis shows that the ability of earnings management practices to predict the dividend policy is driven by ownership concentration. Spliting the sample, we find that the positive influence of earnings management on dividend policy in non-listed private companies is statistically significant only in companies whose shareholders have control (more than 50% of share capital) as opposed to firms with non-concentrated ownership. Our results contribute for the literature around the quality of financial reporting, lengthening these thematic to include non-listed companies.info:eu-repo/semantics/publishedVersio

Testing of typical spacecraft materials in a simulated substorm environment

The test specimens were spacecraft paints, silvered Teflon, thermal blankets, and solar array segments. The samples, ranging in size from 300 to 1000 sq cm were exposed to monoenergetic electron energies from 2 to 20 keV at a current density of 1 NA/sq cm. The samples generally behaved as capacitors with strong voltage gradient at their edges. The charging characteristics of the silvered Teflon, Kapton, and solar cell covers were controlled by the secondary emission characteristics. Insulators that did not discharge were the spacecraft paints and the quartz fiber cloth thermal blanket sample. All other samples did experience discharges when the surface voltage reached -8 to -16kV. The discharges were photographed. The breakdown voltage for each sample was determined and the average energy lost in the discharge was computed

Multivector Fields and Connections. Setting Lagrangian Equations in Field Theories

The integrability of multivector fields in a differentiable manifold is studied. Then, given a jet bundle $J^1E\to E\to M$, it is shown that integrable multivector fields in $E$ are equivalent to integrable connections in the bundle $E\to M$ (that is, integrable jet fields in $J^1E$). This result is applied to the particular case of multivector fields in the manifold $J^1E$ and connections in the bundle $J^1E\to M$ (that is, jet fields in the repeated jet bundle $J^1J^1E$), in order to characterize integrable multivector fields and connections whose integral manifolds are canonical lifting of sections. These results allow us to set the Lagrangian evolution equations for first-order classical field theories in three equivalent geometrical ways (in a form similar to that in which the Lagrangian dynamical equations of non-autonomous mechanical systems are usually given). Then, using multivector fields; we discuss several aspects of these evolution equations (both for the regular and singular cases); namely: the existence and non-uniqueness of solutions, the integrability problem and Noether's theorem; giving insights into the differences between mechanics and field theories.Comment: New sections on integrability of Multivector Fields and applications to Field Theory (including some examples) are added. The title has been slightly modified. To be published in J. Math. Phy

Uma comparação entre Antispams do tipo desafio-resposta e estatísticos: uma experiência da Embrapa Informática Agropecuária.

bitstream/CNPTIA/11085/1/comtec68.pdfAcesso em: 28 maio 2008

Gluon Schwinger-dyson Equation In The Pt-bfm Scheme

Schwinger-Dyson equations provide an appropriate framework for tackling nonperturbative QCD phenomena requiring a continuum treatment. However, an inadequate truncation of this tower of integral equations can compromise the symmetries underlying the theory in question. The synthesis of the Pinch Technique and the Background Field method provides a framework where it is possible to devise a self-consistent truncation scheme, exploiting the Ward identities satisfied by the effective Green's functions that emerge. In this work we review how this truncation scheme is implemented, and show that the new series of dressed diagrams for the background gluon propagator organizes itself in characteristic subsets that are individually transverse. In addition, we discuss how the Background Quantum identity connects the background gluon propagator with the conventional one, computed in the lattice simulations.70613th International Workshop on Hadron PhysicsMAR 22-27, 2015Angra dos Reis, BRAZI

Procedimento para criação do ambiente de armazenamento em banco de dados da Agência de Informação da Embrapa.

Introdução. Apresentação dos comandos utilizados na criação. Do ambiente de trabalho da Agência. Descrição dos comandos utilizados na criação. Do ambiente de trabalho da Agência. Scripts de comandos. Considerações finais.bitstream/CNPTIA/9944/1/doc19.pdfAcesso em:28 maio 2008

Urgent Need for Reduction in Greenhouse Gas Emissions in Industrial Processes: Are We Past the Tipping Point for Global Warming?

In a previous Guest Editorial (Piacentini and Mujumdar, 2007) and an article (Piacentini and Mujumdar, 2009), we analyzed the relation between climate change and industrial processes, mainly related to drying.Fil: Piacentini, Ruben Dario Narciso. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Mujumdar, A. S. . Minerals, Metals & Materials Technology Centre ; Singapur. Institute of Chemical Technology; Indi

Uso de algoritmos genéticos em problemas de localização capacitada para alocação de recursos no campo e na cidade.

Problemas de localização. Descrição do algoritmo genético construtivo.bitstream/CNPTIA/9182/1/COMNICADOTEC10.pdfAcesso em: 29 maio 2008

Uma proposta de solução para uma classe de problemas de roteamento usando a relaxação lagrangeana/surrogate.

Neste trabalho tem-se como enfoque o problema do caixeiro viajante (PCV), no que se refere a obter um limite inferior de boa qualidade para a solução ótima (a melhor solução possível) em um tempo menor do que os métodos propostos na literatura. O objetivo de se obter um limite inferior é para se saber quão próxima da solução ótima está a solução viável obtida.bitstream/item/76070/1/CNPTIA-COM.TEC.-15-01.pd