PowerShell to update NTDS on a Domain Controller

I need help with PowerShell and Active Directory. 

I need to view the NTDS Schedules of our Domain Controllers.  Once I have their current replication schedules, I need to change the NTDS Schedule of a Domain Controller (DC4) to 15 mins

How do I do this with PowerShell?

Using the Active Directory Sites and Services I can update one Domain Controller at a time. However, I would like to use PowerShell.

Help!

(Attached is a Screen Shot of a Domain Controllers NTDS Settings