base on the cisco doc, there is only one DR/BDR in segment. If we had ospf, the setting is as following:
router ospf 10
network 192.168.10.0 0.0.0.255 area 0
network 192.168.15.0 0.0.0.255 area 0
network 192.168.18.0 0.0.0.255 area 0
network 192.168.22.0 0.0.0.255 area 0
network 192.168.25.0 0.0.0.255 area 0
Does it mean that there is one DR on 192.168.10.o segment, one DR on 192.168.15.0 segment .....
it has 5 DR totally. Is it correct?
We might need to qualify it a bit, but essentially yes you are correct that there would be 5 DR.
If the 5 network statements correspond to 5 interfaces (what if there were a 192.168.10.0/25 and 192.168.10.128/25 - they would both match to the first network statement and each could have a DR) and if each of the interfaces are a network type that elects DR, then yes there would be 5 DR.