{"id":1981,"date":"2016-03-17T14:58:38","date_gmt":"2016-03-17T17:58:38","guid":{"rendered":"http:\/\/eic.cefet-rj.br\/portal\/?p=1981"},"modified":"2016-03-30T08:42:12","modified_gmt":"2016-03-30T11:42:12","slug":"exploring-machine-learning-methods-for-the-stargalaxy-separation-problem","status":"publish","type":"post","link":"https:\/\/eic.cefet-rj.br\/portal\/exploring-machine-learning-methods-for-the-stargalaxy-separation-problem\/","title":{"rendered":"Exploring Machine Learning Methods for the Star\/Galaxy Separation Problem"},"content":{"rendered":"<p>Os alunos\u00a0Eduardo Machado, Marcello Serqueira, Riccardo Campisano\u00a0tiveram\u00a0o artigo intitulado \u201c<strong>Exploring Machine Learning Methods for the Star\/Galaxy Separation Problem<\/strong>\u201d aceito no International Joint Conference On Neural Networks (IJCNN). O trabalho foi feito em colabora\u00e7\u00e3o com o Observat\u00f3rio Nacional (ON\/LINEA) representados por Ricardo Ogando, Marcio A. G. Maia e Luiz Nicolaci da Costa. Pelo lado do CEFET\/RJ participaram tamb\u00e9m os professores\u00a0Gustavo Guedes, Eduardo Bezerra e Eduardo Ogasawara.<\/p>\n<p><strong>Abstract<\/strong>: For recent or planned deep astronomical surveys, it is important to tell stars and galaxies apart, a task known as Star\/Galaxy Separation Problem (SGSP). At faint magnitudes, the separation between pointy and extended sources is fuzzy, which makes SGSP a hard task. This problem is even harder for large surveys like Dark Energy Survey (DES) and, in a near future, the Large Synoptic Survey Telescope (LSST) due to their large data volume. Hence, the search for classification methods that are both accurate and efficient is highly relevant. In this work, we present a comparative analysis of several machine learning methods targeted at solving the SGSP at faint magnitudes. In order to train the classification models, the COSMOS survey was used. We use machine learning methods as distinct as artificial neural networks, <strong>k<\/strong> nearest-neighbor, Support Vector Machines, Random Forests and Naive Bayes. The exploratory process was modeled as data centric workflow. The workflow was implemented on top of Hadoop framework and was used to find the best parameter values for each classification method we considered, of which neural networks and random forest present superior performance.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Os alunos\u00a0Eduardo Machado, Marcello Serqueira, Riccardo Campisano\u00a0tiveram\u00a0o artigo intitulado \u201cExploring Machine Learning Methods for the Star\/Galaxy Separation Problem\u201d aceito no International Joint Conference On Neural Networks (IJCNN). O trabalho foi feito em colabora\u00e7\u00e3o com o Observat\u00f3rio Nacional (ON\/LINEA) representados por Ricardo Ogando, Marcio A. G. Maia e Luiz Nicolaci da Costa. Pelo lado do CEFET\/RJ [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[41],"tags":[],"class_list":["post-1981","post","type-post","status-publish","format-standard","hentry","category-artigos","entry"],"_links":{"self":[{"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/posts\/1981","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/comments?post=1981"}],"version-history":[{"count":1,"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/posts\/1981\/revisions"}],"predecessor-version":[{"id":1982,"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/posts\/1981\/revisions\/1982"}],"wp:attachment":[{"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/media?parent=1981"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/categories?post=1981"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/eic.cefet-rj.br\/portal\/wp-json\/wp\/v2\/tags?post=1981"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}