Submitted on: 29 October 2012.
Revised on: 24 December 2012.
Accepted on: 19 January 2013.
___________________Cuaderno Activa---TECNOLOGICO ANTIOQUIA-INST UNIV, FAC INGENIERIA
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Submitted on: 02 September 2017.
Revised on: 20 December 2017.
Accepted on: 01 January 2018.
___________________Cuaderno Activa---TECNOLOGICO ANTIOQUIA-INST UNIV, FAC INGENIERIA
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