property currenttime : 0property previousbreak : 0 as integerproperty currentbreak : 0 as integeron idle set currenttime to time of (current date) set currentbreak to (currenttime / 60 / 60 / 30) as integer if currentbreak is not equal to previousbreak then do shell script "/usr/bin/killall xpchelper" user name "adminuser" password "adminpwd" with administrator privileges set previousbreak to currentbreak end ifend idle