Chapter 12 **X

Managing out-of-controlxl

T processes

| 0bjecl ivesl i ) . (nr . , i t l . , l l ! , r , )s l : r i l r l r l ( i f l r ( r ! r l r i f , , \ ( .ss t r ( i l r l ( . :h(r , t i i !l i , ( i ' r l l , r ' r s l , n l ( g\ l , , f tn!r 'ss infr \ r . I r ! ,1I tJ, . \ , r f rL,r ' lh. rs, , ( ,1 | ( ) r j iR, l , | r r f lc l ( ! l r ( j r rh l r ,1, , ! ) t , r i , I r l . l , js : i l \

t ,Lr l , ) l ( ( r r l , ( ,1 t , , ( \ f . . ! r .l ( ) f ' j ,F i ( lc , n) , r f ! . rus( s (Jr { , rLL t ,1 (r , . l , , j l | , , ! . :s.s

12.1 Introducl ion!I l ls l ( , fn l l r . lhcr lsf(rrs iL, i l i l \ lor ln iuhl , shr! , lLnrr , i (1t ,Rr(rs inr I f ( i \ (r ' r fnt , f , r ' l l .L i l . ) ,1! $ i l l ) i r r r r j I r ] r l r ( l r r r r l t , , fgnr i /ntL) | . h.r ! n\ l ( \ l$ l rh , r ' t ( . .h i r i r r l ' r l f l t r t r r .n l l r r n\ i f l l i r r ( \ . h1,*1\ . r r th.sc r . rs lsh'r i e i t r ,q1 srrrrr l l .u l i r r . to,rbini i l \ , hy luL) l ] l r \ \ lur , r r r , , l i rL,r l l l , r rs i r ia i ! . ( l wi t l t t1 l ! , i r Ief , l l i r ,n i l l lx j I r l r f ( ibb i , t ! l , l f . l l r . ! ln l hnr j ! \ { l j . l t ib' l l r i l ! , ! le,rt, iF l lrnl [rnxp\r inrFtrfrn]fI l n|( l l truir l ! ' .sl t lxrt i IB t ihoir l{ l

r l h!,r 'onl i , l l re d1ul, 'r ir r l t Ntlf ru, ipn|1,h ot l0rht] irdl Ieir ir lp, lr lh!! \ ! j t .Ylf i r h! ia lo! , t l v ! r f t fn! ! lY tc.

l l r a lrdnuldft l l i rg !ori tF,l l ] ! , f lrr ! \ ,11II lp, thF, ptlrduftt int Fpolr l f h.tr9t l r r 1or1r ' r ' " t l t111, ' r ' r l l r r r t r l n 1r , r l rh l r , ' t r i r$r l " , r l ' , i , t r i , , t ,1, , r l r ,bd. ,bb, ' , a ld, l i , l r l iu, l . r . . r r l i I ,n, . l r . ' . l t r " . I r tsdb,, , r ,h, t , ' f l rEi lk),r l tppt rclprnt\ ihi l i ly f(n'pnw,6b lrr4rtt, pff ir iqir l i

' tn! l foq{ lyhi lpdFiFEdtinE plqpNhcrp fprinrr i ihl l i ly f t f , lh8 ' ludl i t ! 0f i tF oritFut If Fr.| ] fr.lemq oi low quflt l i t t dl ihir (1ri f i |g Fiodlrtign, iyhFthpr i f hp fh0 irumtrer

&I 318 Srat istrcal Process Contro

of t.rbleis produccd pcr dav or the amount of herbi.idc obi.rlni'.l lrom .batch r.'actor, then ihcs( pfoblems ire t.rckled {,ithout quL'stion by pro-du(tion personnel. lvhy thcn shotlld problenrs of - sav excessiveproccss !ari.rtion not fall undcr thc same umbrella?

l'roblenrs in proc.'ss opcraLiort arc r.rrc'ly snrgle climens n;l lht'vhare nt least f i !c d imensions:

, f,1,rr(1 or scrvice, nrcluding inPuts,, / t / r , r r , inclu. l ing c\ui t )ment;. ffd,{,1rrl,r('s, timct.rblcs scheclulcs;. f r 'ot , / , , includi f g inh)rm.r t ion;

f r ) ( r 'ss, thf u, . ry lh in i js nro donc.

Ihcin( l is(r inr inJleinvol !cnrontofrus( i r .h/ tcchnic,r lP.oPkirr t ro l rb l ( 'sho{, t i f , t i ( ! rds k) polnr i , /c ni t ( r r t ion h)wrrds thc tc( in i . | l nst)ccts, s ' i t l rtho cr)r t rspondinl t r . lcgxt ion of o lh.r v l t . r l P.r f imcl ' rs In nrnny cis.sthc hLrnrIn, | rnnng( r i I l , r r rd cv( n l in in. i . r l d inr( nsi(nrs hr\ ' . ' n s iEni f i. l r r t L)( , r r ing orr th( i \1rr l l p|1nr lcm in(] i ts sol t r l i rn I | ly sho(r l ( l ro i1. . ignorcd l . ) , i . rk ins . r PR)blcnr olr i o l i ls n i tur . r l fnyiR)nmcrrt nnd Plr-c ing i t i r r . ' l i l 'o t r rk)r \ '

Ih. .nrphnsis () f rny ' tR)uLl lc shoot i r rg ' cf ior t sh{)uld hc ( l i f . .hdt( t r ! r tu ls proLr l ( |n Pft ' \ ( nt i ( $ i ihPr iof i t i | r i r lh. inrsof :

( i ) nuirLr i r ins ( lur l i t ,v o l .ur f t r r t o( ' lPui ,( i i ) purss InrpR^nrnt ' r r ,

( i i i ) f ( r lu. t d. 'vcLoPrk'nl

Qunl i t \ ' issor,rnf( , f i , f . ' \nnrPl( , nrosl not be I dcpnrhnent to bc iHnoft 'd$' lx, ic\ . r 'y th i .g isrunningK'I1, !ots.rddled!vi th lhcr. 'sPonsibi l i t \h)rsolvinit qLrnlitv pr(rbhnrs when th.'y afisc Assocr.rt(d with this Prrcticcarc thc' rlangers of such P('olilc being uscLl .rs sc.pctaonts \\'hc'1

'rPlnn-.tions to scnior nran.rgers a( tr\uired, or bcifg off( r&l as sdcrificiall.mbs r\,hen .ustomcr compl.inis nre b('ing dealt \^'ith lhe ri'sfonsibili ty for . l r ra l i t ) , mrrst a1t ! .11's l ic t ! i th oPer. tors of thc P()cess

'nd ihc rok'

oi QAor any othor support function is clcarl)' to.ssi* in th('nr'ciin,l otthis responsibiliiy. It shotrlcl n('t be accePtnble for an! gfouP tr'Lthin anorginiznt ion ionPPro. l .hanother grolrP $i ththccluest ion, ' \ /chavc gota i roblem, r 'h.r t arc 1ou gonrg io do about i t? ' rxPctt .dvic" mn\, ofcoursc, freqLrcntLy bc iccessnrv b t.lcklo frrticular Pro'ess Pr('blems

Hrvingdcscribed UtoPi., w.'mustn..ept thatthe real $orld is incvit'blyless than perfect. lhe major Problcm is the one of H'hcther

' Process has

the neccsiarv capabilitics r.luircd to meet the requircments' It is againstthis b.ckglou nJthat thc methods in this chaPter arc Presented

tr1

Li r -

t i , t

l i '

n hL

lrr IJ, '1.

I i i r

lhL

&3r I x

r

Manaq ng out-oi-contro processes

12.2 Process impr0vement slrategyI r ( ,cess inrprovcmcni is nci thrr d p!rc scicnce nol JI n. t . t roc{.durcsrr . r ! b. ' pr fscnht bLr i thcsc wi l l nc.r lv i lw.rvs bdx f f t Jforn ingcnlr i r \ , .I is t r . rc l i t ionnl k) st | l .1\ . , rusc rnd r i lect rc l . r t i ( ) r1ships. I lowc\cr. whrn

1.. .11 rr i th n nr l r l l ip l ic i t \ ( ) f p{) tcnLi . l c .Lrscs of Fnnr lems, . r l l of t r ,h i .hrr \o l \c inrPcr l |c l ( tnhr, i t i5 f f . ( t ! .n i lv nd\rnt . r i j .o l rs lo brgi i r r i rh\ t rd jos s 'h i rh i , l (nt i i ! onlr t ) lo.ks of grrJ l rp\ . rs th. sorLfce ( , f lh.l rouhlc lh( r rouPs nr,r \ , t ( ) r f \ r r fp l . , l ) . . r .onrI l rk i i l l in lg lnco a$hr)Lc nR!r ( ) l i {Ni fc ( ,p(rr t i ( r r . IhUs, rh( pi r rp() int l l i t rn spf . i l i (. r ( rsfs nn! i 1 t1. . {s is p,)st l ) ( ) rx\ I .

/ \n rJ ' for l . ' f l I f n. i tc n) L, . . r fphrsi^d nt r l r . ( \ r ls . l is lh. i r i r r t l i . r ti lu( l (s shorLl , l nol . r inr t ( ) J is,( \1 . \ i . f \ th i r ) l l s t r . r ighl , rwr\ Ih is isl i r l iLr r r l \ rnf tJf l . r . r I i s i lu.r t ( ) |s $h(,( . I r ( ,11 r l . l . r i \ (Jht . r ILrLr l .( l r i l , c . rs i l \ .

Effects of srngle fa cto rs

l l rs i ,Jrp()ssi t ) l ( lo s, . l ( lo$n c\ . rv l l r in l l \ !hr t1, s l , ( \ r l ( l b( ,ohsrr \ rd i r l, Jn \ i fg ()u l , r fnr( ss inrpr( \ . lur t i \c f . ise ( ) r t r ( ) i i l r . I r t rs l inrp()r l . rn l,u.s t ( ' ( )hr t ! \ c s lo L{ } ,11s(!r t s 'h, . f ( ln l . ) nr . L, . in i t ( (n l , \ r , \1, r r l . fs t i I it i , r l l \ . lh is f r^ i , l r \ l l r , ( ) i ) f ( ! lL r i l \ l ( i ( ) l r \ . r \ . } l ,s !hL(.s,)r , . fs. t , , r r , fi , i t l t .u] ' r is i l i ,nr i i (1 l i ( \ l ( ! lh l l l ) r ( , r d, . , r { i l l t . ( tLr i l ) | r . , j l i l ! , ,11l) i r . ! I (J l )s, r \ , r l i , i f (n r l . r r r ( r ) l l f . t ! ! r nr , r , , , i l \ ( ) sLrLt .st , iss i l | r . r l r l ( , , r r s{ .swl i rh rr , r \ l r ( r \ . rn, i | ( r l , r l lh i inr . Ih is rr rk l fs i l r { { l i l lc , . , j l e l l . ( ts( iue t ( i ( \ l ' rLpnr. i ,1 .h.rrr [ .s, \ ' . r f ] ( r rs sr t ] ) l ( !s, s l r i l ls . P.(r | l ( .s l i l ls . . l {

l r lR)ul) l ( . \ lx{ , l jg , l r ( l f r \ r ' \s inr t i r ( \ fnur l st l r ( i j , s . lh. f t . l l r i r r } t ( ) lr l , r t , r , r ( ( l r i \ i l i ( f r f r ( ) t r r r l rn.s \h( \ , rsslst in ( l . t . . l i .s l lx , . l r ( \ . ts olr ' l { , r l . rn1.h. , , , l j f i l l r ' ( ' l ] f ( ! lLrni l \ l ( , , , ( ) l ( , l \ )ssi l r l ( r ( l , r l ( r i \ l j i t ,s(( !n( .s

r i rLr( l r r r ( iR r . , r (1, r l ( ) t l t i r )v.st i l t . r lo i ! l ( , ( )L i : { ! \ .s l | l ( ln l , r L( , t . ( t i ( r rt r rn lh on( r !h l , : i t : (or i rnr l r l r l ! i i r rn (nl (e. l rn i f I l t l0dhc, . rw.rv lh( .( ) t ,servef is l t r . i t ( \ l l r ( )nr th, . ( l !n, ihc.ssl l r in l ( rnr . r t !n(s)h. .L, t , j ins. ' r r1 lhr1t( . r t ( f t ln d{,ul) l rb()Lrr ih( \ . r luf ( ) l r lx i r r l ( i rn,rr ior .

I i t l , \ ' l iv( r t r t l r t r ls ( ) t I l . r . f ing Pr( \ r 'ss in! .s l ig,r l ioIs h.r \ , , br0rr l . ! ( 1,) |d. \ l . r t r of th.se b{ 9.r . r r th, ( | t ,nrn,r l , , ,k\ . l f i . r l nml Ine.hinnr l .n$i . r r r ing i L l rLsi fn s. l h( 1)r lnciples . rn, l pf .k. l i f r \ . r r ! , l ro$1,! luni ! . rsr l l ! . rppl i .nbl( , . ( ; .n.r . r l v l r { ( ' . rppf() . r ,h. ,s rrc.r ! . r i lJblr , as { l is.usse{ l in Lh! nr\ t t t ro sdJi(nrs.

The el fccts oi .L\ lL inBle ! . rL.rblesspccd, cifcentrntnxl] nrv havc bt'en

(t .g krnpcf iLrrc, \ 0 l t . rge, t imr,sho$ 11 n) hr\ c becn LmPort . t i f

xI 320 Slat ist icat process Control

othcr sjnrilar *Lrdi{,s. I he pjl,cedu.es of att.fhg one variabte at n tirnrrqi i .JFr \u. , , \ r t r . t . r . l i .u lJr \ .n s1. .at I rnp,d LrburJtur. ,* , rndf , ' , ' l ' l l . l " l : r ' , r i ' . , r , rh t , . \ \a! . . , t " , . r r . , r . hhhn . . rp, . \ f , . ,J r . ,: r rnL\ rn,rr . l I n! . L" . r . r . t . r In{ \ p,r \e.-

. r1. t , ! rnr l t , , 1," Jrr , , . .11 111., ,1_e!t , . . , te. I I r \ ' - , -nr ' . r . r l lv .

^ f rm,,n h.h. j r . , t . ,o, r . ,_ i . t rdn. fen,.d l r ( ,mIn. d l r , r r . {^rr ur I , i l . t f l ,nt to t . r t , \ , rh. . ,ner.r t inn. t rL.Jr , t ( \ t re.ut l_nrJ\ ^L' , ,n lnrnHLl, ' .onr, ,o. , , r_t , , r .hI

. , i t i r t , t I r r r e\ , , r l t t , ,udl-n, ,kno$-n chantts hnve be(,n inrroduced. In thcs. , . .scs rh conhlr t chnrrmcthods of Shcl\,hnrr nrc Lrsrf!t t0 chi,ck on proc.ss stabitii\l

Group factorsn rrn hl , - .1. , \ , l rn! I ,n. i , { , r ,1r t n, , r \ h, . r | | ) l . \. rn, \ . rnr |n.r l , , ' r . ,1 t l r . f . \ - i l . l , r r i t r , r , . , , . . i . , . ,u l tur , l

. r . . r \ . , t . t i rh.r1r.l \ \ I . l ( . , l i f t1, . f r i , . tJ i t !n, . r . r ( t , t , ,n. . , r fn\1, . , r , , i , , r r , . . . , , , , i . , r , r ,^ . r , . i iL.] : ' , ' , , * t , ' " ,*r , , t , t i . , , ,1t s. t t r . I - , !LI qhi , . t , . . , t , , r i , . r , . , r . , . . t \ ,h ll i ) . . r

' . , r ' l r r r l , r ! l \ , r l I 'L. ! , , . | | . , . . i , I t r r . \ . r r . . r tL,r . | l f , r i , , r . r I . , .hr t lo i tcn pf t )v idf impor innt. .us.s of rhosc di f fcr(neos. i t rnce, thc k i ,v t0nr.rk ing.Ll j rshre'r ts,rnd iDpf,) !cnrorrs is i , , knl , r , i " , r ,1. , . , " , , " r , l i i f , ;('n..s d() cxisi, .rnd beinlt .rbk, lo Pint)oinl ihe s(",..,,"',,f tt,,, iff*,,r.",l i i ; , ' l ' , ]1,rA,rr i t l , , . , r . r , r r , r r . r , ru, . rL, t , r . , i . r , , i . r \ r , . l .n\ , .+ i ! t . , . , r .1$ | | | | \ , \ r r l , l r t r , , r r . r . \1, , . r , , r , , , . . i . r , r , . ; , . r r - r , . r , r . r t r . r r . r r r r . , r_,I , . r . , ,1, t r . .1 , t . r t .LI \ r l rvt . r . r t . l . , r rU,r , . r , . r ,1 i , ; r . i / , \ t \ \ i t t r i r r ,r , - - f l t , . . r r , , l \ r i . . .J . 'u, i i . . - J, I r l t r r . l ,n._ir . . . , I r . i . , . f l l r rJ!r1, , \ i , r r t r t ] .,Yr,rrr \ r . ' , r ' r , "L. , \ i I r l , . r r ,Lt L. , t . , r \ , . . r , , , l r . t r \ , .d.L/ ,1t t l i t r "Ulr f , I r I r , . i . \ \ ' . . , . in\ . [ r , .ht ! | | , . . r )_,r , h! t " . , f t , . \ \h. , . , . r ) t . r r , . t r r , ,oitcn rcco|n'z.r n ro(un.u1g n]nJflrn(.tionjng pro.ess bv char.rittt,r;st;cI i , l , l l11", ' . r . , , . " \ " , : r \ . , , ,n, ,L.r , . , , ,nrr , , \ , , , .h, \ . . . n, , r ) i ,nf , , , ,

. r r , l . l . r ' r !p! l \ I r i , , r l , r lvrr . r , l r . . r t . , r . , \ . . . rnn, , t b, nr , , ; , r iz ,Jbr,rnr1, l ,obser\ . t ion nn. l intui t i r )n no nratt( , r how co

n.,,,,,,i,,r. ".

.1:1,:l:i l l j::,;"i;j,; "l r , rn r l \ \ . ,1 r .^t Ar\ , . . r . i .1, \ l Fr iJr t Inr , , i t - l . , t , . r ! : . ,Lrr In. ie, . l m.,r , )

t r . , , - .p. r , . \ ' Lrrr , , , .*niz, .d. ,"np\\ h. . t r r \ i , .ur uh, h. . . r , L,( rhur., " l l l ' , " ' ' " , . , : , , : , , .J1. ' ,b\ .

, r \ , r . {J.rrd, , r rh, . r , r , ,ou.rpn.J,r" , r , , .n n,r , L. , l .n \ i r le( l T11rnr. ) , rApf i , r rut . ! .n i . , i r " tu,n, . , .1,r . . , " . t t . . , rn.melf , .J.

' , i , t . r . t i . ' r rd l l \ h r .p,r nvr\ | | { . r t i , . r t , . _ l fp, , . t tp. l , r r . r . , l, r , r \ r , \ r tF h r t t b, . . , r , . , , c l , t r , - . , l tv

. r1. , . fFr. , , r , i1 l - r . , , , ( . r

?l l : -" : : l , , l l , ' " r ,n, . , r - \ .h,ur i1c r \ , . . r r ; . r , ,onr,1h,11'rh, , pp, , ,p, :_r t r p,r 'F lp i . , \ .pn' i . r l r t r \ , . \ e. , ,J\ {Jge. l l . ,Fc.J\ Ft . r In"J t , ro, ' , . run.-$rr prcvent r?stage oi time, cfiorr an.l materials and will ar.;i.l ernbar,rassment to those in\rt\.cd. lt wilt atso ensurc suppo( for imljtemcntathn ofthc results of rh stt)dv. (See.rtso Chaptcr U.)

q321 &Manaq nq 0r1 0t-c0r l ro processes

glN 12.3 use 0t control charts l0r trouble-sh00tingl f s(nr stLrL{ i .s, lhf purtosc ( i f t l r r d.r tn , ( ) . . t r (D is lo pro! idf rnf( j fr r )n l lof , , I tho .e lnt iorrs l r ip\ hfh\ ( \ ,n vnr iJbtr ,s i I orh. f .nsfs. th. pI ll ) ( ' ! s tu* l ( ) I lnr l $1rvr n) c inr in,rn,r s. i iorrs probkjn t t r . ( lnht l r .Dn l \$,()r . r r r r rn,r l , r f , r l \s i ! r ) l th( ,nr . . rk,(n r f t l ( ,or no((ns.LlL(,nr( ,l l ) . . r l t i r , r l i ( ! r tJ l r . , i , ih() . l r , r f t \ t r ) ( l , r r , r , , r t r r . ( i . \ . l tJ | ( ,1 i | , r f l , r l\ i r r . l \ ot srrrrnlr( i | : i | ! t fn\ ' { t , .s n , inr f t . \ I . r } r r ! . r iL I I r ( , r t l \1 ot | ( ,: ( . l , , r t rnr i stU, l \ i fg r . (sLr i t \ lJ \ r l r i r nr . . r i r r . \ j r , ies ( j j , rsst i t | , r l )1.. . , , r r 's . rk ol l r ! r in( l i t , r l . ( l b\ J)nlLr,rr rs rJ l r r , r i ( tq r( ,U{ oi ( ( ! r ln) l( .h. ' ,1! , r s r \ \ l l \ r ( l { l (J \ !s l , ,nr i l r i . }Jr() ! r , r n, , i .s o s,rnrt , I r , , r r (1 nr( . , rsr ' . , ik r l lh. | t r ,s( . f i , r r i ( ! r ( ) l n.sr rs i | .h, l l j ( fnrnr,rk.st t r . ( t . r r . r | l ) r .( . ,sr l \ , rs\ i I r r . r l { \ l . f i l l ) r ( \ j ( l ( \ n I , iLt In.r) j l l r . f r ( r r , .s. r i . i r | ( ) t, i \ . , i l i l )1. l i , , , i r s i r i r f l . l . r l r r . r t i ( i , i i , t t lk R\L, l t \

lh( ! .nLni L l i , r lnr( , i r ( ! l r \ . ( j l . , , IJ ! . . , r I t j . rb( . r ( ) : , ! tL j . ,u, , , j l n rh, ,1.( l , rL,r i : \ !e , r . t , ) \ , i , i , i [ , l , .cLl , r l , , r ] r ( l nr , r \ \ \ . qLr i tg.st ( , r , \ .s( i lr , i ' , i ' r , r l l r . i l , , , , j r . I r ( t , t \ , , , j r I , r r i r jn( ,1 \Lr( t r ( t r , , ,1. . , , j : t r . \ . . f t , ) [ ( r ] ., , , f \ l ) r \ L l . . \ i ( lor( ( . , ) r eL oI tJ niL. . r v j j l f ( ) , t . , , r l rsr ig, j . r l , t ( , r Iu! ,c oli , )u l ) lL Jh, ( l r , I i t l ( i .s i r ( ) t stJ\ , . l l r . l , f t iht( . , , i . l j t i t i , rL l i ( , r l ( .s htr( . | ,

, , r ' ,1 t r r \ ih l \ I l r ( , f ( , l r i , r ) . i ( i . . i \ ( ) ! l r ( i r r

IhL. I I , I r I i ( , r I ( , , i , . ( i i ( ( r r t ,L, lL l r , r f ls i l r f rs l ,hr ! , . I ( , t L j rcr j . f . t r , r t , lL,r ,i ,so. ' l l \ l r (11. , i$ i l l r t , \ i ( l , r , , . t l r . r t h. l , r ( ! ( \ \s. ,s lst . r t i i l i ( , r l ( , ! , l r ( ,1(() , r ( \ | \ , ) ( l ( r I ( i l ! , ,nr ' ! , r l r , r ! lh. , i i r i ( l i ( , r i ( \ l \ lur , r r r , ) r t r ) t ( r r , l , i ) ls ,Lf , r t r , 's , , l , t . r i r \ l l r r in, I r \ t r t ' r h l , s lx!nin| , , t ,1) l i ( r t i , i , rs, t l r ( . i r r i l i , i l, rsrr 1s:hrtr \ I

' , i l l l l . ] , ( \ . :s i ! , ! ) i i I s t , r t i ! l t . , i l (L)r ] t r ( ) t , ! , ( l Iu\ t iu, j

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l l , r iLrs l l ) ( nr , ( l . , l r i l ( , ( ( . , r I r , r l Is t . ( ) r L()r i l f ( ) l (h. , r ls , r t ( ! r ( . { i . (n( . . , l r l . t l r ' . ,1r \ . i , t ln!rb( i I . r I r ( i ( , . : : r ( , h, i ( l ( r r t r .LI r \ t t i ( ) r r , ILh

l , r ) \ \ l .LIr f , ) l l l , ' I r ( ! , , :s. , , j (1 l r^! l i \ot \ , f . r t .L l i5r t \ { ) f ( \ t | , . ( t \ ,Vh,. ,1l l 'c Ls.onr l r i , i t ( l $ i ih,rr ! rk l ( , rst , rn i l i , r : ( i l ( i r r l , ( ) t ( t r , I t t ) r r r . i f .5.I l r . r lh ( l r . rg,r)s is ( i i . , r r5.s r) l I r ,b l . I js s i l l b{ . t ) ( ) \ . j t ) t ( .

lh i \ Lr( \ ,k ( , rn.{ i l ro l1 l ( , | , ( ) \ i (1. rh, . i , i l i I i , r r ( In(r* l .LI ! . ( , t . \ ( . f \l )n)L1\s lh. ' l i : r1\ l r l r . r1 t ,J \ , ,1\e t , r r ' l r l , .nr \ ( iu iL l , rn.{ . ( nI ( l_\ l ) r L i \ . r r{ ) . th. i fhr fJt . l . t i ( ! r ( ) t . rDLr() l .h. l ls tof fn\r ,ss i . r f rL^.njort . rn( li f ( r rL)L{ s| lb l ing. l lxJr , . r f r | r . r r , " . r ! r ( l \ . i f ( ) rLt f r l f ,n\ t rh i rhL1eiel , rpo,r .oI t r ( ) l (h, '11snlurfr) . fssct . rR not i r ) rL, I t r ) t tVh.rr i (nt( , \ !s is.r .r l t ( ,nrPl n) s l r r fh i f r ' th( p. t tenrs inhr rnr ious ( , r r ( .gor i fs. I h( i tk , r , r ( .r ( i i dcf in l \ r , n()r is th, . l i r t e\ lLru5l i \c l ho t . r r rn 'nrr is b.r : t \ l ( ! r lh!r !1r \ 's i f \ i h i .h ot l t ( ' f l Lrr t |1) l s i tunr i (nr \ nr . rv r f is . , i . . l r ln, i r , , iJ f . ts ( ! r\ nfrou\ ( ( ! r ) cf t l r ts.

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