Refresh parent window from Child window on close JavaScript

ive refer to last question  asked by Sumeet.

i've done the same but on child gridview.

i got an error message

'ShowPopup' is not a member of 'ASP.vessel_vesselequipment_aspx'.  and Expression expected. 

can anyone tell me where am i wrong?

refer to :http://www.aspforums.net/Threads/679969/Refresh-parent-window-from-Child-window-on-close-JavaScript/