[eclipse-clp-users] reduced cost based filtering technique

hello,

I want to know how I can implement reduced cost based filtering technique in my code.
I wrote a code for an employee timetabling problem but I can't get the optimal solution, so I want to use this technique to reduce the domains more by considering the LP relaxation of the problem, how can I do this? Is there any similar examples that use this technique? also do I need anything besides Eclipse? 

thank you
Sharareh