???????????????2??????????????9??????,????????????????????23???????????????,??????????1???????1????,????????????????50?????????????,???????49??????????,??????????????45?????,??????????????????????2??10??????????

??????????????,??????????,?,????????????????????????,???????,???????????,?????????????

????????,???1????????????????????????????????,??????????????????????9?????30???????1????????????????????1?????,?1????????????1??,???????????????????????2??????????2??3????????3,???????????????,???????????,????????????

???????,????????,???????????????????,??????????,??????????????????????,?????????????????,?????,??????????????

?,?????????32????????????,??(VAR)????????????????,??????????,?????????????????????,?????

???????????????????,????,????????9?1?,???????????????????????50?,????????,????????????,?????????

???????????????,?????????,2?????12???????????????,?,?2???????????20??????????????,?,?????,?????????????

???????????????????,?????????????????:“??????????????????????????????,????,????????????????,?????????,????????????????????,??????????????????????”

??? ?? ??????????:????????? ??“????????”????

?? ??????,?????????

????:1?????????:??????????

2????????

3????????sn

4??????????

5???????????

???????????????2??????????????9??????,????????????????????23???????????????,??????????1???????1????,????????????????50?????????????,???????49??????????,??????????????45?????,??????????????????????2??10??????????

??????????????,??????????,?,????????????????????????,???????,???????????,?????????????

????????,???1????????????????????????????????,??????????????????????9?????30???????1????????????????????1?????,?1????????????1??,???????????????????????2??????????2??3????????3,???????????????,???????????,????????????

???????,????????,???????????????????,??????????,??????????????????????,?????????????????,?????,??????????????

?,?????????32????????????,??(VAR)????????????????,??????????,?????????????????????,?????

???????????????????,????,????????9?1?,???????????????????????50?,????????,????????????,?????????

???????????????,?????????,2?????12???????????????,?,?2???????????20??????????????,?,?????,?????????????

???????????????????,?????????????????:“??????????????????????????????,????,????????????????,?????????,????????????????????,??????????????????????”

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