Grey-Box Model: An ensemble approach for addressing semi-supervised classification problems

In this paper, we propose a novel and interpretable grey-box ensemble using a selflabeled approach for semi-supervised classification problems. The prospective greybox ensembles a more interpretable whitebox model with a black-box technique. This scheme could guide the comparatively data expensive white-box component with the results from the more accurate black-box part. We evaluate the proposal in an inductive learning setting showing good performance in partially labeled datasets

Study of star-forming galaxies in SDSS up to redshift 0.4: I. Metallicity evolution

The chemical composition of the gas in galaxies versus cosmic time provides a very important tool for understanding galaxy evolution. Although there are many studies at high redshift, they are rather scarce at lower redshifts. However, low redshift studies can provide important clues about the evolution of galaxies, furnishing the required link between local and high redshift universe. In this work we focus on the metallicity of the gas of star-forming galaxies at low redshift, looking for signs of chemical evolution. To analyze the metallicity contents star-forming galaxies of similar luminosities and masses at different redshifts. With this purpose, we present a study of the metallicity of relatively massive (log(M_star/M_sun)>10.5) star forming galaxies from SDSS--DR5 (Sloan Digital Sky Survey--Data Release 5), using different redshift intervals from 0.04 to 0.4. We used data processed with the STARLIGHT spectral synthesis code, correcting the fluxes for dust extinction, estimating metallicities using the R_23 method, and segregating the samples with respect to the value of the [NII]6583/[OII]3727 line ratio in order to break the R_23 degeneracy selecting the upper branch. We analyze the luminosity and mass-metallicity relations, and the effect of the Sloan fiber diameter looking for possible biases. By dividing our redshift samples in intervals of similar magnitude and comparing them, significant signs of metallicity evolution are found. Metallicity correlates inversely with redshift: from redshift 0 to 0.4 a decrement of ~0.1 dex in 12+log(O/H) is found.Comment: 11 pages, 9 figures, Accepted for publication in A&

The merging/AGN connection: A case for 3D spectroscopy

We discuss an ongoing study of the connection between galaxy merging/interaction and AGN activity, based on integral field spectroscopy. We focus on the search for AGN ionization in the central regions of mergers, previously not classified as AGNs. We present here the science case, the current status of the project, and plans for future observations.Comment: 4 pages, 3 figure, Euro3D Science Workshop, Cambridge, May 2003, AN, accepte

Pineapple by-products integrated valorisation towards functional foods

This work was financially supported by CBQF under the FCT – Fundação para a Ciência e a Tecnologia through project Multibiorefinery – Multi-purpose strategies for the valorisation of a wide range of agroforestry by-products and fisheries: A step forward in the creation of an integrated biorefinery, (POCI-01-0145- FEDER-0066) and the project UID/Multi/50016/2019 and by PhD grant SFRH/BD/104074/2014 to Débora Campos.info:eu-repo/semantics/publishedVersio

Pineapple by-products integrated valorisation towards functional foods

info:eu-repo/semantics/publishedVersio