kill Specific Session in Oracle

kill Specific Session in Oracle 

conn hr/hr@orcl

select inst_id,sid,serial#,terminal from gv$session where username='HR';

   INST_ID        SID    SERIAL# TERMINAL
---------- ---------- ---------- ----------------
         1          8        598 WIN-DATAHO
         1        227       7107 QUIUMPC


alter system kill session '227,7107,@1';

How to Check Current User Session Sid, Serial# 

conn hr/hr@orcl

SELECT SID, SERIAL# FROM GV$SESSION
WHERE AUDSID = Sys_Context('USERENV', 'SESSIONID')
AND SID = Sys_Context('USERENV', 'SID');