μu791??￡oμu?t°u?tê?????±±o￡1??÷￡?x???èy(2)
??iu??1???°?è¨?uod?′?-di?é2?μ??′????
?°?-o?￡???iy??á?￡??a??d?1????μê2?′￡???3?à′???°?u????ê￥3?μ±?d′oá?o???1?￡?????ê￥??ê?ê2?′???÷￡???2??á2??aμà°é￡????éê?iiμ???x??a????￡?x??ao?è?￡?·to?o?μ???ê??êêuμ?±|±′￡?μ±?ê3¤éu′oμ??i???-o?????ê￥???a??d′??á?o????tx?iiêé￡?o?3?êà￡????oè?o?μ?′?á??iê??ê??·¨±|￡??±
?uiid?′?ê±o2ê?d??d?e?a￡???′?2u??μ?éu?i?u?-o?oa????o￡μ±?d2???1?μ′?￡
?°????ê￥???-?-?a?????÷￡??°3￡è?2?oa?μμ?μ?￡?o?à′?′?è￡?′o1?￡??i??ê?iy??2??é?uiy?μ￡????a??d?1???è′?μμ?i·i·ê?μà￡???o?μ±?d?uê???od??oáμ?oi?￥￡???μà?y?μμ???ê???μ?￡?±±o￡1??÷￡??a???é??è?é?′o?é·3á?￡????a?′′|???y??￡??±
??o￡???d￡??-o?é2?????i?u??i·á÷xa￡?2????ox?ê??éμ?à′áuè￥???￡
′?ê±′??i￡???d??d2???·o?eà′o???oo?u??oa?￡?a??d?1?????è?iˉd??′?y￡?μ?o??′?iê?oé′oooi¨μ?è???￡?x??o?a??????μ??′è?é??a?uo???′o?é·3￡???ê?μ1?1?￡
??ou?a?uμ?d?1???￡??-o??é2??o??é±á??￡o???xo??é±￡?ê????iá?￡?i′?iá?￡????oμ￡á??￡μ??-o??é2??àd??a??d?1???éié???odê2?′±￡?uμ?ê????￡
?i??ê?êà?xμ±?dμ?o?1u1??÷3?o??1?°o?oooμ￡??¤?à????￡?1??????àμ???μ?￡??é??2?2?±￡?¤?￡???a?uo????yx?1??÷￡??1ê?o???d?o￠xo￡??i?u?u±±o￡?a??dx??μ?μ?·?1?éi??oax??ˉ￡??a?μ?÷ê2?′￡?
??·?2?ê?od±￡?uμ?ê???￡??iê?odè??u°μ?d±￡?¤?￡x??o??od3?ê?￡?é?o|??·?o?μ?μ?￡?éu?àá￠?i?i3éá??êia￡?
?uo???￡?oa?-o????a?uo???ii?y?td°￡?iˉd??′?yμ?d?1???3?ê?￡???ê??t??è?o?o2x?2?3?à′μ??￡
?°°￥?-?-1?è?￡??o??á?￡?°???éié?μ?i??1?1???o??o?ou???￡???μá??o￡???μ￡′yμ??e?e￡??±
?i?u?a??ê±oo￡?′o°x?èx???èyo??a?u?μμà?￡?μ?°????￡???o???3à??μ?d????1?uo￡??μ±?d??iu????￡??uê±????￡?o?μào￡?u?i?ox??-o?o??ˉ??è￥?￡
?°i??1?1￡??oμ?d?1??i?i￡??o??à?odê2?′i??1?1?￡?a?u°é￡??o·?????è￥è?o?￡??±
?a?u?a??????μ??°￡??d?-o?d??d2???od???td|2?μ?μ??d???￡??á?o???￡????1ê????¨·???·???è￥?￡
ê￡μ??aá?·oè?o???±?￡?
?°o?￡?d???1i￡???éié??÷?÷od??′oou??μ?i??1?1￡??aê2?′2???x???èy3?￡??±±??ao???￡?x???èy?uê±??o??-±?μ???àái?i?￡?·?·eêuμ?ii′oμ??ˉ?uo?°?￡???ê?o???d?o￠xo?￡
μ?o?è????a?a
?°o?￡???2???x???èy￡?x???èy?ix??o??￡?oi???μê2?′à′x?￡???êé2???iμ￡???i??1?1???io22???iμá??￡o?￡??±
??iu??1???°?è¨?uod?′?-di?é2?μ??′????
?°?-o?￡???iy??á?￡??a??d?1????μê2?′￡???3?à′???°?u????ê￥3?μ±?d′oá?o???1?￡?????ê￥??ê?ê2?′???÷￡???2??á2??aμà°é￡????éê?iiμ???x??a????￡?x??ao?è?￡?·to?o?μ???ê??êêuμ?±|±′￡?μ±?ê3¤éu′oμ??i???-o?????ê￥???a??d′??á?o????tx?iiêé￡?o?3?êà￡????oè?o?μ?′?á??iê??ê??·¨±|￡??±
?uiid?′?ê±o2ê?d??d?e?a￡???′?2u??μ?éu?i?u?-o?oa????o￡μ±?d2???1?μ′?￡
?°????ê￥???-?-?a?????÷￡??°3￡è?2?oa?μμ?μ?￡?o?à′?′?è￡?′o1?￡??i??ê?iy??2??é?uiy?μ￡????a??d?1???è′?μμ?i·i·ê?μà￡???o?μ±?d?uê???od??oáμ?oi?￥￡???μà?y?μμ???ê???μ?￡?±±o￡1??÷￡??a???é??è?é?′o?é·3á?￡????a?′′|???y??￡??±
??o￡???d￡??-o?é2?????i?u??i·á÷xa￡?2????ox?ê??éμ?à′áuè￥???￡
′?ê±′??i￡???d??d2???·o?eà′o???oo?u??oa?￡?a??d?1?????è?iˉd??′?y￡?μ?o??′?iê?oé′oooi¨μ?è???￡?x??o?a??????μ??′è?é??a?uo???′o?é·3￡???ê?μ1?1?￡
??ou?a?uμ?d?1???￡??-o??é2??o??é±á??￡o???xo??é±￡?ê????iá?￡?i′?iá?￡????oμ￡á??￡μ??-o??é2??àd??a??d?1???éié???odê2?′±￡?uμ?ê????￡
?i??ê?êà?xμ±?dμ?o?1u1??÷3?o??1?°o?oooμ￡??¤?à????￡?1??????àμ???μ?￡??é??2?2?±￡?¤?￡???a?uo????yx?1??÷￡??1ê?o???d?o￠xo￡??i?u?u±±o￡?a??dx??μ?μ?·?1?éi??oax??ˉ￡??a?μ?÷ê2?′￡?
??·?2?ê?od±￡?uμ?ê???￡??iê?odè??u°μ?d±￡?¤?￡x??o??od3?ê?￡?é?o|??·?o?μ?μ?￡?éu?àá￠?i?i3éá??êia￡?
?uo???￡?oa?-o????a?uo???ii?y?td°￡?iˉd??′?yμ?d?1???3?ê?￡???ê??t??è?o?o2x?2?3?à′μ??￡
?°°￥?-?-1?è?￡??o??á?￡?°???éié?μ?i??1?1???o??o?ou???￡???μá??o￡???μ￡′yμ??e?e￡??±
?i?u?a??ê±oo￡?′o°x?èx???èyo??a?u?μμà?￡?μ?°????￡???o???3à??μ?d????1?uo￡??μ±?d??iu????￡??uê±????￡?o?μào￡?u?i?ox??-o?o??ˉ??è￥?￡
?°i??1?1￡??oμ?d?1??i?i￡??o??à?odê2?′i??1?1?￡?a?u°é￡??o·?????è￥è?o?￡??±
?a?u?a??????μ??°￡??d?-o?d??d2???od???td|2?μ?μ??d???￡??á?o???￡????1ê????¨·???·???è￥?￡
ê￡μ??aá?·oè?o???±?￡?
?°o?￡?d???1i￡???éié??÷?÷od??′oou??μ?i??1?1￡??aê2?′2???x???èy3?￡??±±??ao???￡?x???èy?uê±??o??-±?μ???àái?i?￡?·?·eêuμ?ii′oμ??ˉ?uo?°?￡???ê?o???d?o￠xo?￡
μ?o?è????a?a
?°o?￡???2???x???èy￡?x???èy?ix??o??￡?oi???μê2?′à′x?￡???êé2???iμ￡???i??1?1???io22???iμá??￡o?￡??±