We would like to acknowledge, Ricardo Bianchini, Denise Bandeira, Patricia Kayser, Luis Fernando Pias de Castro, and Kish Shen for their major contribution and influence to this work. We would like also to thank all students that collaborated to the success of this project.
This work has been supported by the CNPq project Appelo/ProTem-CC. The work presented here has been partially supported by funds granted to LIACC through the Programa de Financiamento Plurianual, Fundação para a Ciência e Tecnologia and Programa PRAXIS.