????:1???????????:??????sn

2???98????

3?????

4?????

5????????100???

??????12?????????4??????????????????? (????????????? ?)??,?????????12??4????12?????????46?????????????,?,??,?????????????????,???“??????”???

?SAR(??)??,?,??????????

12???4??????????????????????,???????????????,???????????????? ????

??“?”????,??????????????????????,?????????????????????????????????,???????300??????????????????????450?,???????1.4????1.8?????????????,??????????

???28???????(?????)

?????????????????:????????????????????