Secured Communication of Speech Signal Using the Discrete Cosine Transform Based on Hyperchaos-System. - Noureddine Aissaoui; Fethi Demim; Abdenebi Rouigueb; Hadjira Belaidi; Ali Zakaria Messaoui; Kahina Louadj; Abdelkrim Nemra; Ahmed Allam; Yasmine Saidi; Said Sadoudi; Mohamed Salah Azzaz (ICINCO (2), 2023)