Assuming you are talking about codespace memory segment (where the program and data tables go):

. org 0000h ;Program Start
.start: ljmp init
. org 0003h
.v_int0:
. ljmp v_int0

For ram memory you are reserving a place and not load a value (ram powers up indeterminant and must be loaded or initialized by the program). You have several types of memory segments for ram.

iseg ;reserve space in indirect ram
. org 0080h ;(80-FF)
ival: ds 1
ibfr: ds 8

dseg ;reserve space in direct ram
. org 0040h ;(00-7F)
dval: ds 1
dbfr: ds 8

xseg ;reserve space in external ram
. org 0000h ;movx commands
xval: ds 1
xbfr: ds 8

bseg ;reserve space in indirect ram
. org 0 ;(20h-3Fh)
bflg_lo: dbit 1
bflg_hi: dbit 1

-Jay C. Box