expdp old_user_name/password directory=dir_name dumpfile=xxxx.dmp tables=table1_name,table2_name
impdp system/oracle directory=dir_name dumpfile=xxxx.dmp remap_schema=old_user_name:new_user_name
expdp old_user_name/password directory=dir_name dumpfile=xxxx.dmp tables=table1_name,table2_name
impdp system/oracle directory=dir_name dumpfile=xxxx.dmp remap_schema=old_user_name:new_user_name