You use the 
Adjust
Cost - Item Entries batch job to adjust value entries so that
you use the correct adjusted cost for updating the general ledger
with the Post Inventory Cost to G/L batch
job. Cost adjustment is generally about forwarding any cost changes
from inbound entries to the related outbound entries. It may be
relevant after posting any inventory transaction, but mostly in
connection with:
inbound transactions
item charges
finishing production orders
The adjust Cost - Item Entries batch job processes only value entries that have not yet been adjusted. Entries created by this batch job will receive the posting date of the item ledger entries to which they are directly related, except when the related item ledger entry is in a closed accounting period, in which case the value entry will receive the posting date that you have entered in the request form. A date is considered to be in a closed accounting period when it is earlier than the date in the Allow Posting From field in the general ledger setup.
The costing method on each item card determines how the program calculates the adjustment. You can read more about costing methods under Costing Method.
The batch job does not update the general ledger automatically
unless the you have selected Automatic Cost Posting in the
inventory setup. To update the general ledger manually, you must
run the Post
Inventory Cost to G/L batch job.
Click OK to start the batch job. If you do not want to run the batch job now, click Cancel to close the window.
Fill in the field as follows:
Closed Period Entry Posting Date: In this field, enter the date that should appear as the posting date on adjustment entries whose original entries are in closed accounting periods.
You can also set the program up to perform automatic cost adjustment every time you post inventory transactions. This allows you to operate with more accurate inventory and WIP values and profit statistics without having to rely on other users running the Adjust Cost - Item Entries batch job periodically.