Kill Process ERROR !!!

Dear master

How to kill a process in postgresql. I use ps auxw | grep postgres to see
status....

it-linux:/usr/local/pgsql/data# ps auxw | grep postgres
postgres   197  0.0  7.1 318528 64244 ?      S    08:07   0:00
/usr/local/pgsql/bin/postmaster
postgres   206  0.0  0.1 319484 1244 ?       S    08:07   0:00 postgres:
stats buffer process
postgres   207  0.0  6.1 318516 55580 ?      S    08:07   0:00 postgres:
stats collector process
yudha      571  0.0  0.1  2448 1068 pts/0    S    09:56   0:00 psql
-Upostgres csa
postgres   572  0.0  8.8 319940 79208 ?      S    09:56   0:00 postgres:
postgres csa [local] idle
postgres   582  0.5  9.6 320284 86968 ?      S    10:02   0:00 postgres: it
csa 192.168.0.234 idle
postgres   587  1.1 10.4 320972 93636 ?      S    10:04   0:00 postgres:
postgres csa 192.168.0.111 idle
postgres   588 14.6 10.0 320536 90448 ?      S    10:04   0:01 postgres:
postgres csa 192.168.0.100 idle
postgres   589  2.0  7.3 318844 66232 ?      S    10:05   0:00 postgres:
checkpoint subprocess
postgres   590  0.0  7.9 320020 71592 ?      R    10:05   0:00 postgres:
postgres csa 192.168.0.222 SELECT
root       592  0.0  0.0  1332  424 pts/1    S    10:05   0:00 grep postgres


I want to kill process no 582, I use kill -9 582 but all user become
disconnect  look at below


it-linux:/usr/local/pgsql/data# ps auxw | grep postgres
postgres   197  0.0  7.1 318564 64264 ?      S    08:07   0:00
/usr/local/pgsql/bin/postmaster
postgres   206  0.0  0.1 319484 1244 ?       S    08:07   0:00 postgres:
stats buffer process
postgres   207  0.0  6.1 318516 55580 ?      S    08:07   0:00 postgres:
stats collector process
yudha      571  0.0  0.1  2448 1068 pts/0    S    09:56   0:00 psql
-Upostgres csa
root       599  0.0  0.0  1332  424 pts/1    S    10:06   0:00 grep postgres

how to kill only one process ?

TIA

Best Regards
Aris Wendy