FND_GLOBAL.APPS_INITIALIZE for initializing session in Oracle Apps R12

 select organization_id
  from hr_operating_units
where name = :p_name;

exec mo_global.set_policy_context('S',:p_org_id);


select u.user_id user_id, r.responsibility_id resp_id,
       r.application_id resp_appl_id, r.responsibility_key,
       sg.security_group_id security_group_id
  from fnd_user u,
       fnd_user_resp_groups ur,
       fnd_responsibility r,
       fnd_security_groups sg
 where u.user_name          = :p_user_name
   and r.responsibility_key = :p_responsibility_name
   and ur.responsibility_id = r.responsibility_id
   and ur.user_id           = u.user_id
   and ur.security_group_id = sg.security_group_id;


begin

  fnd_global.apps_initialize
    (  user_id                    => :p_user_id
    ,  resp_id                    => :p_resp_id
    ,  resp_appl_id           => :p_resp_appl_id
    ,  security_group_id   => :p_security_group_id
    );

end;