Below you can see couple of examples:

exec dbms_apply_adm.set_parameter('&APPLY_NAME', 'disable_on_error', 'Y');

exec dbms_apply_adm.set_parameter('&APPLY_NAME','PARALLELISM','1')

exec dbms_capture_adm.set_parameter('&CAPTURE_NAME
','_CHECKPOINT_FREQUENCY','2000')

BEGIN
dbms_capture_adm.set_parameter(capture_name => '&CAPTURE_NAME',
                               parameter  => '_SGA_SIZE',
                               VALUE      => '300');
END;
/