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1398 Q=y@ 'h}QW u= Qta |UOvyt 8375 "X '1/2 |xQ=tW '35 2 |xQwO Original Article |=yp=v=m QO u=}QH |OOa |R=UpOt |}xkvRwP ?mQt`]kt =@ |OwQu=J}B |QDmO |wHWv=O |WQi xt]=i Q=}Wv=O |v=t=U |Q}@m =[Qr=O@a Q=}Wv=O |vtJ =[QOtLt |QDmO |xDNwt;Vv=O hw]a u}UL u=yiY= |DavY x=oWv=O 'u=Qta |UOvyt |xOmWv=O QO "OQ=O |O=}R C}ty= '=yOwQu=J}B w =ysN Q}Ut QO x} wv=F |=yu=}QH j}kO |R=UpOt |=y|oS}w |UQQ@ x@ 'swivB= Q= Ri=sQv \}Lt QO |OOa |R=UpOt =@ 'Q[=L VywSB u}= |= Q@ "CU= xOW xDN=OQB OwQu=J}B Q}Ut QO ?mQt p=v=m l} QO u=}QH |m}rwQO}y pL RANS |ROrwv}Q |xOW|Q}o\UwDt |=yx]@= Q pt=W 'sm=L CqO=at 'Qw_vt |RQt \}=QW w QopL ?=NDv= =@ 'R=@ |=yp=v=m QO u=}QH |R=iwO Q=DiQ OwHw =@ "Ov=xOW R= 'Q[=L VywSB QO "OQm pOt R=ilD CQwYx@ = Q =yu; u=wD|t ?; K]U |= Q@ ?U=vt |=ypOt R= xDiW; u=}QH |R=UpOt |= Q@ w xO=iDU= ?; O= R; K]U |= Q@ uQ=kD |RQt \QW R= uDiQo xrY=i =@ 'xOt; CUOx@ G}=Dv j@] "CU= xOW xO=iDU= k ! w k " |oDiW; u=}QH =@ CyHsy |x@=OQo l} xm |Qw]x@ &O@=}|t V}=Ri= |[Qa u=}QH CQOk 'sN G=D G=D |=OD@= =D |[Qa u=}QH u}= "OwW|t p}mWD |vwQ}@ pL=U |xWwo pLt QO |[Qa "OwW|t Q= QmD pmW u}ty x@ |Oa@ Gwt pw] QO , =OOHt w O@=}|t xt=O= |Oa@ sN f.farshi@cv.iut.ac.ir akabiri@cc.iut.ac.ir mchamani@cc.iut.ac.ir h.atoof@me.iut.ac.ir Q} w=v |=yx]@= Q '?mQt p=v=m 'OwQu=J}B 'x}wv=F |=yu=}QH %|O}rm u=oS=w "|ROrwv}Q \UwDt TmwDU= xtOkt "1 ?}mQD ?mQt p=v=m QO OwHwt |x}wv=F |=yu=}QH =@ w O=H}= RmQt R= R} Qo |wQ}v Q}F -=D Q=wWO Q=}U@ = Q ?mQt |=yp=v=m QO u=}QH p}rLD '|Oa@xU |=ysR}v=mt "OvwW|t |=yVr=J R= sN Q}Ut QO ?mQt |=yp=v=m x@ \w@Qt p=Ut 'u}= Q@=v@ [1] "OvR=U|t "CU= R=@ |=yp=v=m K= Q] u=UOvyt w u= QoWywSB |rY= 'x}wv=F |=yu=}QH "CU= Q=wWO x} wv=F |=yu=}QH |=yQDt= Q=B s}kDUt |Q}oxR=Ov= Owta QwLt =} u=}QH`]kt |xLiY QO xm OvDUy CaQU TvH R= |}=yQ=OQ@ CaQU OYQO 3 =D 2 OwOL 'Q=Okt Q_v R= w Ov};|t OwHwx@ u=}QH |=DU= Q Q@ uotyQ}e 'QwmPt |=yu=}QH -=Wvt "OvDUy s}kDUt |=yp=v=m QO u=}QH \UwDt |=yQ=DN=U '|OwQu=J}B ?mQt |=yp=v=m QO [2] "CU= u=}QH |oDiW; uOw@ QO |J}B Q=t CQwYx@ x} wv=F |=yu=}QH |=yQ=DN=U "OvDUy QDxO}J}B u=}QH R=e; |x]kv '=yQ=DN=U u}= R= |m} u=}=B |x]kv w OvwW|t Qy=_ =yOwQu=J}B w s}kDUt |=yQ}Ut QO x} wv=F |=yu=}QH u}tND w |}=U=vW "CU= |Qo}O |=yV}=tR; u} QDQ@Dat [53] "CU= xOw@ |}xOQDUo |=yVywSB`w[wt 'xO}tN jraD u=DUrov= s=ovtQ}@ x=oWv=O x@ 'x}wv=F |=yu=}QH |xv}tR QO xDiQoCQwY w A |QU s}kDUt |=yp=v=m VN@ wO QO w CU= hwQat FCF x@ xm 'OQ=O u}= QO R}v |OwOLt |OOa C=ar=]t [6] "CU= xOW s=Hv= B |QU OwQu=J}B |OOa |R=UpOt R= xO=iDU= =@ '2002 p=U QO 'p=Ft |= Q@ "OQ=O OwHw xv}tR =yp=v=m QO u=}QH j}kO |xar=]t CyH |[=} Q |=ypOt |xaUwD |= Q@ xQ=wty =yp=v=m "OwW |}=U=vW j}kO Qw]x@ =yu; QO u=}QH Q=DN=U =D CU= xOW VqD , qwtat "OvQ=O R}v CWO?q}U '|rY= VN@ Q@ xwqa w OvQ=Ov s}kDUt Q}Ut , qwtat u=}QH xm |t=ovy "O@=}|t u=}QH |rY= p=v=m p=v=m |rY= VN@ QO ?; u=}QH Q}}eD p=v=m QO u=}QH |wor= 'OwW|t OQ=w CWO?q}U x@ |rY= VN@ R= p=v=m hqDN= "OwW|t p}O@D ?mQt Cr=L x@ xO=U Cr=L R= p=v=m 'Cr=L u}= QO "Ovm|t OwW|t |WQ@ |[Qa |=yx}q O}rwD Ea=@ 'CWO?q}U w |rY= p=v=m u}@ CaQU "OvQw;|t O}OB 'OvDUy u=}QH QO pO=aD sOa R= |W=v xm = Q |t_vt |=yx@=OQo =yu; w "OwW|t R}v QDxO}J}B u=}QH Q=DN=U 'OQ=O |OwQu=J}B Q}Ut p=v...