Prasanta
LOG_EAM_CI_6 is Enhancement Pack 6 for the PM module which contains a group of new functionality that the customer can choose to switch on: Enterprise Asset Management Part 6 - Business Functions (SAP Enhancement Package 5 for SAP ERP 6.0) - SAP Library
A new function called "Call Horizon in Days" is part of this Enhancement Pack and uses switch EAM_SFWS_MPLAN_OPEN_HORIZ_DAYS to activate it.
Have a look at this OSS Note: http://service.sap.com/sap/support/notes/1675417
PeteA