I agree with Ambient! muhammadfekry_2010 did not even ask a question. Too often I've seen this sort of post. After someone goes to a lot of trouble with detailed explanations, the OP comes back saying "Oh I know all that, I just needed to know XYZ." Spending "his" time on a preliminary Google search or whatever, to formulate questions about the bits and pieces that he "doesn't" understand is prefered. Especially for a "final project". Was this title assigned to him, or did he pick it with no idea of what he was getting.
"ecg holter monitor circuit" comes up with a complete papers, including formulas and schematics. So, what help does he need?
Ken