?????????????????????!??????|????
?????? ????? | ???? ?????
???,“????,??????”“???,??”?????
?????,???,???
???????????????
?????????,????????
???
??????????????????,????????????????????,???????,???????,???????
?????????????D,?????????????????????,?????
????,???????D??,???D???????????
???
????,???????????????????
??????
1.??????
??:?,???????????????????,????1000~1200?????????????????????????????,?????????
????D:?????D?????????,?????(?????????????20??????)???????D????????(???????????????????????)?????
???:?????????????,????????????????????????,??????????????????,????,???
2.????????????
??:??????????????????,???,????,?????????????,??,??????????????
??:?????????????????????????,????????????,??,??????????
??????:???,??,???,???????
??????????
???????????
?????
????????,?????????????????X???(DXA)?????????X???????????,?????????T????=-2.5,????
??????
?????????
????????
??,????????????,??????????????????,????????????????????????????????????????,?????????,????
?????????:????????+??????????????????,???????????????????????
?????:??????????????????,??????,??,?????????,????????????
????????:??????????????? ?????????????
????:???????