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Page 1: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 2: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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� � � � � � � � � � � � � � � � � i u a l u g h g p f l w w | h � g u f p s ` j � l j l w w f w v ` m � � u l u g ` b d� � j l w q ` j g u a m f w ` b q h u ` u a f v w l h h ` s p g j f v u h f l j v a m f u a ` p h i l v w l h h ` s ` � u g m g � l u g ` b

l w q ` j g u a m h z a g v a b f g u a f j v ` m � � u f b ` j l � � j ` � g m l u f l b | p f j g l u g f h ` s u a f ` � f v u g fs � b v u g ` b d � � j z ` j � i g b s l v u i z l h g b h � g j f p | u a f h g m � w f � m f u a ` p ` s x � f b p w f | i o f � u il b p o g m h z ` j u a i l b p u a f h g m � w f � m f u a ` p ` s n f w p f j l b p t f l p d

� a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m g h g b a f j f b u w | � l j l w w f w d � a f l h g v g p f l ` s u a fl w q ` j g u a m g h u ` � f j s ` j m v ` b v � j j f b u h f l j v a f h g b m � w u g � w f p g j f v u g ` b h d � a f h f h f l j v a f h l j fs j f f ` s l b | g b u f j p f � f b p f b v g f h i h ` u a f g b s ` j m l u g ` b j f � g j f p v l b f v ` m � � u f p g b � l j l w w f w d

y v f b u j l w j f h � w u ` s ` � j z ` j � g h u a f v ` b f j q f b v f l b l w | h g h s ` j ` � j l w q ` j g u a m d { |j f � g j g b q ` b w | u a l u u a f s � b v u g ` b f v ` b u g b � ` � h w | p g ! f j f b u g l w f ` f j l ` � b p f p w f f wh f u i z f v l b � j ` f u a l u l h � h f � f b v f ` s u a f � ` g b u h q f b f j l u f p | u a f m � w u g � p g j f v u g ` b l wh f l j v a l w q ` j g u a m v ` b f j q f h u ` l h u l u g ` b l j | � ` g b u ` s u a f ` � f v u g f s � b v u g ` b d � a g h g h

Page 3: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

` s q j f l u g b u f j f h u h g b v f z f � b ` z ` s s f z v ` b f j q f b v f j f h � w u h s ` j � j l v u g v l w p g j f v u h f l j v al w q ` j g u a m h d

~ f l w h ` � j f h f b u b � m f j g v l w j f h � w u h g b p g v l u g b q u a l u u a f m � w u g � p g j f v u g ` b l w h f l j v a l w �q ` j g u a m g h j ` � h u i f f b g b u a f � j f h f b v f ` s b ` g h f d � � j j f h � w u h g b v w � p f v ` m � l j g h ` b hz g u a u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m i u a f m f u a ` p ` s h u f f � f h u p f h v f b u i l b p l � l h g � n f z u ` b m f u a ` p d � b f h � j � j g h g b q v ` b v w � h g ` b ` s ` � j b � m f j g v l w u f h u h g h u a l u u a fn f w p f j � t f l p h g m � w f � l w q ` j g u a m g h b ` u j ` � h u d

~ f v w ` h f z g u a h ` m f v ` m m f b u h l ` � u s � u � j f p g j f v u g ` b h ` s j f h f l j v a d

Page 4: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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� z ` � w p w g � f u ` u a l b � u a f m f m f j h ` s m | v ` m m g u u f f � f l v a ` b f a l h m l p f l bg m � ` j u l b u v ` b u j g � u g ` b u ` u a g h z ` j � d y b p | { ` | p v ` b g b v f p � j h u m f i l b p u a f b m |v a l g j m l b i u a l u u a f w l h u l j q � m f b u b f f p f p u ` v ` m � w f u f u a f v ` b f j q f b v f � j ` ` s z l hv ` j j f v u � a f u a f b � � h a f p m f u ` l m ` h u h l u g h s | g b q q f b f j l w g � l u g ` b d } f b } f b b f p | h a l j f pa g h � b ` z w f p q f ` s � l j l w w f w v ` m � � u l u g ` b l b p � ` g b u f p m f u ` z l j p h l f j | v w f f j w ` l p l w l b v g b q h v a f m f d � g v a l j p � l � g l p f h f j f h h � f v g l w v j f p g u s ` j f f j l q j f f g b q u ` l v v f � u m fg b u ` u a f q j l p � l u f � j ` q j l m d o f g h l w h ` j f h � ` b h g w f s ` j g b u j ` p � v g b q m f u ` ` � u g m g � l u g ` bu a f ` j | d � s w l u f i a f a l h h a l j f p a g h � b ` z w f p q f ` s u a f u a f ` j | s ` j p f h v f b u m f u a ` p h iz a g v a a l h a f w � f p h a l � f p u a f � b l w s ` j m ` s m | l j q � m f b u h d � a l f l w h ` f b � ` | f p ` � jm l b | v ` b f j h l u g ` b h ` b g h h � f h l h p g f j h f l h m � h g v i m g b ` j g u g f h i l b p m l v a g h m ` d

� ` z f h � f v g l w u a l b � h u ` m | v a l g j m l b i _ ` a b e f b b g h d o f l h � f p m f u ` h u l | i q l f m fu a g h � j ` w f m u ` z ` j � ` b i l b p m l p f m f u ` � q a d � ` z f l q j f l u p f l w u ` a g h g b g m g u l w fh u | w f ` s m ` u g l u g ` b � o g h � b f j j g b q j f h � ` b h f u ` m | w l u f h u j f h � w u z ` � w p f f g u a f j � � ` � j fz j ` b q d ` j � � a l u v l b u � ` h h g w | f u j � f d � z a g v a ` s v ` � j h f m l p f m f l w w u a f m ` j fp f u f j m g b f p u ` � j ` f u a l u � z l h i g b s l v u i j g q a u d n ` z a f m ` l b h u a l u � l m l w z l | h j g q a u il h g s u a f j f z f j f b ` v ` b b f v u g ` b d

� z ` � w p l w h ` w g � f u ` u a l b � u a f m l b | ` u a f j � f ` � w f l u � g v f s j ` m z a ` m � a l f w f l j b f pm � v a � � g v a l j p { | j p a f w � f p g h ` w l u f u a f w l h u w g b � b f f p f p u ` v ` m � w f u f m | v ` b f j q f b v fj f h � w u d � g b p l � ` j v � ` b l b p } f g u a k ` ` � f j a l f u l � q a u m f m � v a l ` � u v ` m � � u f j h l b pv ` m � � u l u g ` b d n l b v | g b h � j q h a l j f p u a f f l j w | i p g � v � w u | f l j h ` s q j l p � l u f h v a ` ` w d

Page 5: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

k l u a | x l m � f w h f b u ` ` � � � z a f j f n l b v | w f s u ` ! d k l u a | l b p } l j f b ~ g w w g l m h ` b h � ! f j f pu a j ` � q a b � m f j ` � h p j l s u h ` s m | u a f h g h � g u g h f u u f j s ` j u a f g j f ! ` j u h d

� g b l w w | i � z ` � w p w g � f u ` u a l b � m | a � h l b p i t g v a l f w � f z g h d o f z l h u a f � j h u i u j � f f w g f f j g b u a g h z ` j � � � m l b l q f p u ` v ` b g b v f a g m u a l u � z l h j g q a u f s ` j f � a l p f f bv ` b g b v f p m | h f w s d o g h s l g u a g b m | m l u a f m l u g v l w l g w g u g f h a l h � � h a f p m f s � j u a f j u a l bl b | ` b f f w h f u a ` � q a u � ` h h g w f d o g h q ` ` p u l h u f a l h w f s u g u h m l j � ` b l w w u a g h z ` j � d

Page 6: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 7: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 8: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 9: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 10: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 11: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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u g ` b l w � f g b s ` j m l u g ` b � u a f h f l w q ` j g u a m h b f g u a f j j f � g j f b ` j f h u g m l u f i g b l b | p g j f v uh f b h f i p f j g l u g f g b s ` j m l u g ` b u ` p f u f j m g b f l p g j f v u g ` b ` s p f h v f b u d x f f j l w ` s u a f p g �j f v u h f l j v a m f u a ` p h � g b � l j u g v � w l j u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m � � � � l b p u a f� l u u f j b h f l j v a l w q ` j g u a m ` s o ` ` � f l b p _ f f f h � � � � � a l f w ` b q f b � ` | f p � ` � � w l j g u |g b u a f v ` m m � b g u | ` s v ` m � � u l u g ` b l w h v g f b u g h u h d � a f h f l w q ` j g u a m h a l f j f m l g b f p � ` � �

� w l j s ` j � j l v u g v l w j f l h ` b h d � s u f b i � l j u g v � w l j w | g b f � � f j g m f b u l w h f u u g b q h i p f j g l u g f hl j f h g m � w | � b l l g w l w f d � b l p p g u g ` b i s � b v u g ` b l w � f h l h f p ` b f � � f j g m f b u l w p l u l l j f` s u f b � b ` g h | � g d f d i u a f | v l b ` b w | f u j � h u f p u ` l s f z p g q g u h ` s l v v � j l v | � h ` u a l u � b g u f �

p g ! f j f b v f l � � j ` � g m l u g ` b h m l | � j ` f � b j f w g l w f d � g b l w w | i m ` h u ` s u a f p g j f v u h f l j v am f u a ` p h l j f f l h | u ` � b p f j h u l b p i f l h | u ` � j ` q j l m i l b p f l h | u ` � h f d

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g v l w ` � u g m g � l u g ` b v ` m m � b g u | f v l � h f i s ` j u a f m ` h u � l j u i u a f | w l v � l b | v ` b f j q f b v fu a f ` j | � u a f | l j f f � v f f p g b q w | h w ` z u ` v ` b f j q f i f f b g b u a f b f g q a ` j a ` ` p ` s l h ` w � u g ` b �

l b p u a f | f g u a f j p ` b ` u v ` b f j q f u ` l u j � f h ` w � u g ` b i ` j f w h f u a f | v ` b f j q f � � � � h w ` z w | iz a f b u a f � j ` w f m g h � b ` u h m l w w � z a f j f | � b ` u h m l w w z f m f l b u f b ` j m ` j f l j g l w f h d e f h � g u f u a f h f j f h f j l u g ` b h i u a f l v u g f w g u f j l u � j f g b h � v a � f w p h l h l b l w | u g �v l w v a f m g h u j | � f d q d � � � i � � � i � � � � i � � � � i � � � i � � � � i � � � � i l b p � � � � � h � q q f h u h u a l u � j l v u g v l wv ` b h g p f j l u g ` b h ` s u f b z g b ` � u ` f j � f j v f g f p p g h l p l b u l q f h d

� � j g b f h u g q l u g ` b ` s p g j f v u h f l j v a m f u a ` p h p f h f j f h s � j u a f j v ` m m f b u i u a f j f s ` j f ih g b v f g u g h l p g h u g b v u p f � l j u � j f s j ` m u a f v � j j f b u f m � a l h g h ` b u a f � h f ` s � l h g � n f z u ` bm f u a ` p h g b ` � u g m g � l u g ` b d � ` � j f h f j f u a f h ` � b p u a f ` j f u g v l w � j ` � f j u g f h ` s u a f h f �

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m f u a ` p h v ` b h g p f j ` b w | ` b f h f l j v a p g j f v u g ` b l u f l v a g u f j l u g ` b d ~ f u a ` � q a g u z ` � w p f` s g b u f j f h u u ` s ` v � h i g b h u f l p i ` b v ` b p � v u g b q l m � w u g � p g j f v u g ` b l w h f l j v a u a l u v ` � w p ff � f v � u f p g b � l j l w w f w d � a f p g j f v u h f l j v a m f u a ` p h h � q q f h u f p l b l u � j l w z l | u ` f � � w ` j fu a g h l � � j ` l v a d

� f h f l j v a f j h g b ` � u g m g � l u g ` b q f b f j l w w | l q j f f u a l u u a f j f l j f u z ` m l g b l j f l h z a f j fg m � j ` f m f b u g b u a f h � f f p ` s f � f v � u g ` b s ` j ` � u g m g � l u g ` b l w q ` j g u a m h v l b f m l p f d� g j h u i h g b v f m l u j g � ` � f j l u g ` b h v ` b u j g � u f h g q b g � v l b u w | u ` u a f v ` h u ` s � l h g � n f z u ` b� j ` v f p � j f h i g m m f p g l u f q l g b h v l b f j f l w g � f p | f m � w ` | g b q l p l b v f h m l p f g b � l j l w �w f w b � m f j g v l w w g b f l j l w q f j l d � b s l v u i k ` w f m l b l b p � g � � � � s ` � b p u a l u u a f f � v g f b v |` s u a f g j m f u a ` p h s ` j h ` w g b q h | h u f m h ` s b ` b w g b f l j f � l u g ` b h ` b p g h u j g � u f p m f m ` j |m � w u g � j ` v f h h ` j h p f � f b p f p f j | m � v a ` b u a f f � v g f b v | ` s u a f w g b f l j l w q f j l h � j ` � �

u g b f h l l g w l w f s ` j u a f h f m l v a g b f h d y h l v ` b h f � f b v f i u a f | p f ` u f p l q j f l u p f l w ` su a f g j g b g u g l w j f h f l j v a f ! ` j u u ` p f f w ` � g b q l b f � v g f b u � l j l w w f w u j g l b q � w l j h ` w f j s ` j lp g h u j g � u f p m f m ` j | m � w u g � j ` v f h h ` j � � � � i � � � � d

x f v ` b p i h g b v f s � b v u g ` b f l w � l u g ` b h v ` b h u g u � u f l h g q b g � v l b u � ` j u g ` b ` s u a f v ` h u g bb � m f j g v l w ` � u g m g � l u g ` b i ` b f v w f l j z l | u ` f � � w ` g u � l j l w w f w m l v a g b f h g h u ` a l f p g ! f j f b u� j ` v f h h ` j h v ` m � � u f s � b v u g ` b l w � f h v ` b v � j j f b u w | d x v a b l f w � � � � h � q q f h u f p u a l u z a f bu a f f l w � l u g ` b ` s u a f s � b v u g ` b g h f � � f b h g f l b p u a f q j l p g f b u g h v l w v � w l u f p | � b g u fp g ! f j f b v f h i u a f b u a f j f l j f h g m � w f l � � j ` l v a f h u ` p f f w ` � g b q � l j l w w f w � b v ` b h u j l g b f p` � u g m g � l u g ` b l w q ` j g u a m h d � b u a g h h f u u g b q i l b l u � j l w z l | u ` � h f � l j l w w f w m l v a g b f h g hu ` v ` m � � u f i g b � l j l w w f w i u a f � s � b v u g ` b f l w � l u g ` b h j f � g j f p s ` j u a f � b g u f p g ! f j f b v fl � � j ` � g m l u g ` b u ` u a f q j l p g f b u d � a g h ` h f j l u g ` b s ` j m h u a f l h g h s ` j u a f h � h f � f b uz ` j � | { | j p i x v a b l f w l b p x a � w u � i � � � l b p � � i ` b � l j l w w f w � l h g � n f z u ` b m f u a ` p hs ` j � b v ` b h u j l g b f p ` � u g m g � l u g ` b d

� a f � f | s f l u � j f ` s u a f � l j l w w f w l w q ` j g u a m z f a l f p f f w ` � f p g h u a l u g u g b u j ` p � v f h lm � w u g � p g j f v u g ` b l w h f l j v a g b u ` u a f p f v g h g ` b � m l � g b q s j l m f z ` j � ` s u a f h f � f b u g l w n f w p f j �

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t f l p h g m � w f � l w q ` j g u a m d � l u a f j u a l b � h g b q � � � � s � b v u g ` b f l w � l u g ` b h u ` v ` b h u j � v ul � b g u f p g ! f j f b v f l � � j ` � g m l u g ` b u ` u a f q j l p g f b u s ` j l h g b q w f i l w f g u h ` � a g h u g v l u f p ip g j f v u g ` b ` s h f l j v a i z a | b ` u � h f � � � � s � b v u g ` b f l w � l u g ` b h u ` h f l j v a g b � p g h u g b v u p g �j f v u g ` b h � y b f � l m g b l u g ` b ` s ` u a u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m l b p u a f � l u u f j bh f l j v a l w q ` j g u a m ` s o ` ` � f l b p _ f f f h h � q q f h u f p l j f l h ` b l w f z l | u ` v ` ` j p g b l u f h � v al h f l j v a d � b l p p g u g ` b i u a g h l � � j ` l v a p g p b ` u j f � g j f u a f h ` w � u g ` b ` s l b | w g b f l j h | h u f m h` s f � l u g ` b h i z a g v a m f l b u u a l u u a f j f z l h b ` b f f p u ` p f ` u f l u u f b u g ` b u ` � l j l w w f w l w q ` �

j g u a m h s ` j b � m f j g v l w w g b f l j l w q f j l d y b l p p g u g ` b l w s f l u � j f ` s u a g h l � � j ` l v a i j f f l w f p | u a f v ` b f j q f b v f l b l w | h g h i g h u a l u u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m v ` b u l g b h lb l u � j l w h u j l u f q | s ` j l u u l v � g b q u a f w ` l p l w l b v g b q � j ` w f m u a l u a l h � w l q � f p m � v a ` su a f z ` j � f g b q p ` b f u ` � � l j l w w f w g � f m ` j f v ` b f b u g ` b l w ` � u g m g � l u g ` b m f u a ` p h d

� � j u a f j m ` j f i z f z g h a f p ` u a u ` � j f h f j f u a f s f l u � j f h ` s u a f p g j f v u h f l j v a m f u a ` p hz a g v a m l � f u a f m h ` � ` � � w l j g b v f j u l g b v g j v w f h i l b p u ` l p p j f h h u a f v ` b v f j b h j l g h f p | u a ` h f z a ` � f h u g ` b u a f v ` b u g b � f p � h f ` s p g j f v u h f l j v a m f u a ` p h d � a � h z f z l b u f pl b l w q ` j g u a m u a l u p g p b ` u j f � g j f p f j g l u g f g b s ` j m l u g ` b � u z l h h u g w w j ` � h u d ~ fz l b u f p l b l w q ` j g u a m u a l u z ` j � f p z f w w g b h g u � l u g ` b h z a f j f u a f s � b v u g ` b l w � f h z f j fb ` g h | l b p | f u z l h f l h | u ` � b p f j h u l b p l b p u a � h f l h | u ` g m � w f m f b u d ~ f l w h ` z l b u f p l bl w q ` j g u a m u a l u v ` � w p a l b p w f m ` j f u a l b u f b l j g l w f h f ! f v u g f w | d � g b l w w | i z f z l b u f pl b l w q ` j g u a m u a l u z l h l v � f p | l v ` b f j q f b v f u a f ` j | d

� a f j f h � w u ` s ` � j g b f h u g q l u g ` b h g h l m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m z a g v a g h lb f z p g j f v u h f l j v a m f u a ` p u a l u v l b f f l h g w | g m � w f m f b u f p ` b � l j l w w f w m l v a g b f h � g ug h � � � l � l j l w w f w g m � w f m f b u l u g ` b ` s l b f � g h u g b q h f � f b u g l w p g j f v u h f l j v a l w q ` j g u a m d � bl p p g u g ` b i z f a l f p f f w ` � f p l v ` b f j q f b v f u a f ` j | s ` j u a g h l w q ` j g u a m u a l u z f f w g f fv l b f f � u f b p f p u ` h f f j l w ` s u a f ` j g q g b l w p g j f v u h f l j v a l w q ` j g u a m h s ` j z a g v a z f � b ` z` s b ` � j g ` j v ` b f j q f b v f j f h � w u h d � g b l w w | i z f a l f f g p f b v f u ` h � q q f h u u a l u u a f m � w u g �

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p g j f v u g ` b l w h f l j v a l w q ` j g u a m l w h ` � j f h f j f h m l b | ` s u a f � f j s ` j m l b v f s f l u � j f h u a l u z fz f j f g b u f j f h u f p g b m l g b u l g b g b q d

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p g f b u u ` j f h ` w f ` u a ` s u a f h f g h h � f h d � s u a f q g f b � ` g b u g h b ` u l w ` v l w m g b g m g � f j i u a fb f q l u g f q j l p g f b u � j ` g p f h l h f l j v a p g j f v u g ` b s ` j z a g v a p f h v f b u g h q � l j l b u f f p g s u a fh u f � u l � f b g b u a l u p g j f v u g ` b g h h � � v g f b u w | h m l w w d � b l p p g u g ` b i u a f q j l p g f b u p f h v j g f hu a f j l u f ` s v a l b q f ` s u a f s � b v u g ` b s j ` m u a f q g f b � ` g b u i z a g v a l w w ` z h s ` j l � l b u g u l u g fb ` u g ` b ` s � h � � v g f b u p f v j f l h f u ` � j f f b u h u f � h u a l u l j f f g u a f j u ` ` w ` b q ` j u ` ` h a ` j u d� b u a f � j h u v l h f i u a f l f j l q f j l u f ` s p f v j f l h f g b u a f s � b v u g ` b l w � f s j ` m u a f v � j j f b ug u f j l u f u ` u a f b f � u g u f j l u f m � h u f l u w f l h u h ` m f � j f h v j g f p s j l v u g ` b ` s u a f g b g u g l w j l u f` s p f v j f l h f g b u a l u p g j f v u g ` b d � b u a f h f v ` b p v l h f i u a f j l u f ` s p f v j f l h f ` s u a f s � b v u g ` b �g b u a f h f l j v a p g j f v u g ` b l u u a f b f z g u f j l u f m � h u f w l j q f j u a l b h ` m f � j f h v j g f p s j l v u g ` b` s u a f j l u f ` s p f v j f l h f g b u a f h f l j v a p g j f v u g ` b l u u a f u a f v � j j f b u g u f j l u f d � a f h f u z `j f � g j f m f b u h s ` j h � � v g f b u p f v j f l h f l j f � b ` z b l h u a f y j m g � ` � ` w p h u f g b v ` b p g u g ` b h d

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t ` j f h ` � a g h u g v l u f p w g b f h f l j v a l w q ` j g u a m h g b v ` j � ` j l u f v � j l u � j f g b s ` j m l u g ` b � h f v �

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Page 30: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 39: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 40: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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p g f b u d o ` z f f j i u a f j f g h f b ` � q a h u j � v u � j f g b u a f l w q ` j g u a m u ` f b s ` j v f h u f � w f b q u av ` b u j ` w z g u a ` � u f b s ` j v g b q u a f y j m g � ` � ` w p h u f g b � ~ ` w s f v ` b p g u g ` b h d

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Page 41: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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y h h � m f u a l u � �� g h b ` u l h u l u g ` b l j | � ` g b u d � s h ` i � f m m l � d � q � l j l b u f f h u a l u u a fm � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m z g w w � j ` p � v f l b f z f h u f j u f � g b l � b g u f b � m f j` s g u f j l u g ` b h d ~ f z g w w p f b ` u f | � � u a f g u f j l u g ` b z a g v a � j h u � j ` p � v f p l b f z f h u f j u f � d ~ f a l f l w h ` l h h � m f p u a l u � � � �� � g h v ` m � l v u d � a � h i s ` j l w w � � � � i u a f j ff � g h u h l u w f l h u ` b f f j u f � � � h � v a u a l u u a f f j u g v f h � �� � � � � � � � �� � d x g b v f � � � �� � g h ` � b p f p i u a g h g m � w g f h l ` � b p ` b u a f w f b q u a ` s u a f f p q f � �� � � d x g b v f u a f j f h v l w g b qs l v u ` j h l j f v ` b h u l b u l v j ` h h l w w f p q f h s ` j l w w g u f j l u g ` b h i u a f j f w l u g f w f b q u a h ` s l w w f p q f hg b u a f h g m � w f � j f m l g b u a f h l m f l v j ` h h l w w g u f j l u g ` b h ` s u a f l w q ` j g u a m d � a g h g m � w g f hu a f f � g h u f b v f ` s � � � l h j f � g j f p d

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Page 42: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 60: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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r l j � g b h ` b l b p o � u v a g b h ` b � � � � f � � f j g m f b u f p z g u a v a l b q g b q u a f h g � f ` s u a f g b g u g l wh g m � w f � � h f p u ` h u l j u u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m d � a f | v ` b v w � p f p u a l u l j | �

g b q u a f h g � f ` s u a f g b g u g l w h g m � w f � p g p � j ` p � v f h g q b g � v l b u l j g l u g ` b h g b u a f b � m f j ` ss � b v u g ` b f l w � l u g ` b h j f � g j f p u ` h ` w f f l v a � j ` w f m d k ` b h f � f b u w | i u a f | h � q q f h u f pu z ` h u j l u f q g f h s ` j p f u f j m g b g b q u a f g b g u g l w h g � f ` s u a f h g m � w f � d { ` u a h u j l u f q g f h j f � g j fw g b f h f l j v a f h u ` p f u f j m g b f u a f w f b q u a h ` s u a f f p q f h g b u a f h g m � w f � d r l j � g b h ` b l b po � u v a g b h ` b j f � ` j u f p m ` p f h u p f v j f l h f h g b u a f b � m f j ` s s � b v u g ` b f l w � l u g ` b h j f � g j f pu ` m g b g m g � f u a f s � b v u g ` b z a f b f g u a f j ` s u a f h f h u j l u f q g f h z f j f � h f p u ` p f u f j m g b f u a fh g � f ` s u a f g b g u g l w h g m � w f � d � a f u j l p f � ` ! g h u a l u m ` j f z ` j � i g b u a f s ` j m ` s w ` v l w w g b fh f l j v a f h i m � h u f p ` b f f s ` j f h u l j u g b q u a f l w q ` j g u a m d

~ f m l � f u a f s ` w w ` z g b q ` h f j l u g ` b h l ` � u u a f h g � f ` s u a f h g m � w f � g b u a f m � w u g �p g j f v u g ` b l w h f l j v a l w q ` j g u a m � y h z f a l f l w j f l p | b ` u f p i u a f m � w u g � p g j f v u g ` b l w h f l j v al w q ` j g u a m l � u ` m l u g v l w w | l p � � h u h u a f h g � f ` s u a f f b u g j f h g m � w f � | j f h v l w g b q u a f w f b q u a h` s l w w u a f f p q f h g b u a f h g m � w f � d � a f � j ` w f m i � l j u g v � w l j w | z a f b u a f h g m � w f � g h u ` `w l j q f i g h u a l u u a f l w q ` j g u a m g h f j | v ` b h f j l u g f g b g u h j f h v l w g b q � g u ` b w | a l w f h ` jp ` � w f h u a f w f b q u a h ` s u a f f p q f h � g b p f � f b p f b u ` s l b | s � b v u g ` b g b s ` j m l u g ` b l v � g j f pp � j g b q u a f v ` � j h f ` s u a f j f � f v u g ` b h u f � d c l v a j f h v l w g b q j f � g j f h u a f v ` m � � u l u g ` b` s � b f z s � b v u g ` b l w � f h i z a g v a m l � f h u a f � j ` v f h h v ` h u w | d � s z f v ` � w p l v v f w f j l u f

Page 64: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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u a f j f h v l w g b q i z f m g q a u h f f l h g q b g � v l b u p f v j f l h f g b u a f u ` u l w b � m f j ` s s � b v u g ` bf l w � l u g ` b h j f � g j f p u ` m g b g m g � f u a f s � b v u g ` b d

� b f g p f l z f a l f v ` b h g p f j f p i � u b ` u | f u g m � w f m f b u f p i l p p j f h h f h u a f g h h � f ` sj f � f l u f p v ` b u j l v u g ` b h d � b v f z f a l f v ` m � � u f p u a f j f � f v u g ` b h u f � z f a l f f b ` � q ag b s ` j m l u g ` b u ` v ` b h u j � v u l b l � � j ` � g m l u g b q � l p j l u g v l w ` b q f l v a ` s u a f � f p q f h l p � l �

v f b u u ` u a f f h u f j u f � d � u z ` � w p u a f b f � ` h h g w f u ` � j f p g v u i l u b ` m g b l w l p p g u g ` b l wv ` h u i l b l � � j ` � g m l u f m g b g m g � f j l w ` b q f l v a ` s u a ` h f p g j f v u g ` b h d ~ f p ` b ` u z l b u u a fh g m � w f � u ` f v ` m f l b | h m l w w f j u a l b b f v f h h l j | i h ` z f v a ` ` h f u a l u m g b g m g � f j z a g v aj f � g j f h u a f w f l h u j f p � v u g ` b g b u a f h g � f ` s u a f h g m � w f � d n ` z i z f v a ` ` h f l h u j g v u w |� ` h g u g f � ` z f j ` s u a f v ` b u j l v u g ` b s l v u ` j u a l u z g w w j f p � v f u a f h g m � w f � u ` l h g � f u a l u g hv w ` h f u ` u a l u j f � g j f p u ` g p f b u g s | u a f � j f p g v u f p m g b g m g � f j d � a f f ! f v u ` s u a g h l v v f w f j l �

u g ` b g h u a f h l m f l h j f � f l u f p w | v ` b u j l v u g b q u a f h g m � w f � i a ` z f f j i g u f w g m g b l u f h l w w u a fg b u f j f b g b q s � b v u g ` b f l w � l u g ` b h d � p f l w w | i u a f b f z h g m � w f � z g w w � j ` p � v f l b f z f h u f j u f � z a g w f l ` g p g b q l w w u a f g b u f j m f p g l u f v ` m � � u l u g ` b h d � a f ` u a f j l p l b u l q f ` s u a g hl � � j ` l v a g h u a l u g u � j f h f j f h u a f � � f p h u f � h g � f h ` s u a f l w q ` j g u a m z a g w f m l � g b q h ` m fl u u f m � u u ` f u u f j l � � j ` � g m l u f u a f m g b g m � m l w ` b q l u w f l h u ` b f ` s u a f f p q f h d

� a f h l m f l � � j ` l v a v ` � w p f � h f p u ` l v v f w f j l u f u a f f � � l b h g ` b h u f � i � u g u g hw f h h v w f l j u a l u u a g h z g w w h g q b g � v l b u w | g m � j ` f u a f � f j s ` j m l b v f ` s u a f m � w u g � p g j f v u g ` b l wh f l j v a l w q ` j g u a m d � b u a f � j h u � w l v f i ` � j f � � f j g f b v f g b p g v l u f h u a l u u a f l w q ` j g u a m j l j f w |u l � f h m ` j f u a l b u z ` f � � l b h g ` b h u f � h g b l j ` z d � a � h g u z ` � w p h f f m u a l u u a f f � u j lz ` j � i a ` z f f j m g b g m l w i z ` � w p f p g � v � w u u ` � � h u g s | d t ` j f g m � ` j u l b u w | i j f v l w w u a l ug s l b f z f h u f j u f � g h l v v f � u f p � z a g v a z ` � w p f u a f v l h f g s u a f f � � l b p f p h g m � w f �

z f j f l v v f � u f p � u a f b l u u a f b f � u g u f j l u g ` b u a f ` b f p g j f v u g ` b z f � f f � g h u a f p g j f v u g ` bz a g v a � j ` p � v f p u a f b f z f h u f j u f � � g d f d i u a f f p q f � � � �� � �� � d � a � h z f v ` b u g b � f u `h f l j v a l w ` b q l p g j f v u g ` b s ` j z a g v a z f a l f l w j f l p | h f f b p f h v f b u d � b u a f m f l b u g m f ia ` z f f j i z f v ` b h g p f j � � b f z h f l j v a p g j f v u g ` b h i ` b f ` s z a g v a m l | � j ` p � v f f f b

Page 65: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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g q q f j p f v j f l h f h g b u a f s � b v u g ` b l w � f l u u a f f h u f j u f � s ` j u a f h l m f j f w l u g f h u f �h g � f d � a � h z f l j f w f h h w g � f w | u ` � � j h � f f f j w l j q f j h u f � h g b l h g b q w f p g j f v u g ` b l u u a ff � � f b h f ` s f u u f j j f w l u g f p f v j f l h f g b l b f z p g j f v u g ` b d

� b h � m m l j | i u a f j f l j f b ` l � u ` m l u g v � j ` v f p � j f h s ` j v a ` ` h g b q u a f g b g u g l w h g � f ` s u a fh g m � w f � d � u h a ` � w p f v w f l j u a l u u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m v l b v f j u l g b w |j f v ` f j s j ` m l l p g b g u g l w q � f h h i � u h � v a l p � � h u m f b u h � � l j u g v � w l j w | g s u a f h g m � w f �

g h u ` ` w l j q f � m l | � j ` f u ` f � g u f v ` h u w | d ~ f a l f h � q q f h u f p ` b f � ` h h g g w g u | s ` j` f j v ` m g b q u a g h � j ` w f m i � u u a g h g p f l a l h b ` u | f u f f b u f h u f p d ~ f v w ` h f | b ` u g b qu a l u l h g b u a f v a ` g v f ` s h a l � f i l b | g b s ` j m l u g ` b � b ` z b l ` � u u a f s � b v u g ` b v l b i l b ph a ` � w p i f � h f p u ` p f u f j m g b f u a f h g � f ` s u a f g b g u g l w h g m � w f � d

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� a f j f g h b ` � f h u g ` b � u u a l u u a f ` j g f b u l u g ` b ` s u a f h g m � w f � z g w w l ! f v u u a f � j ` q j f h h ` s ` u a u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m l b p u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m d� a f j f l h ` b g h h g m � w f � u a f ` j g f b u l u g ` b p f u f j m g b f h u a f h f l j v a p g j f v u g ` b h d r l j � g b h ` bl b p o � u v a g b h ` b � � � � s ` � b p u a l u l j | g b q u a f ` j g f b u l u g ` b ` s u a f g b g u g l w h g m � w f � a l pl p j l m l u g v f ! f v u s ` j l w w u a f s � b v u g ` b h u a f | u f h u f p � h g b q u a f n f w p f j � t f l p h g m � w f �

l w q ` j g u a m d � a f | j f h u j g v u f p u a f g j l u u f b u g ` b u ` � j ` w f m h z g u a ` b w | u z ` l j g l w f h l b pu a f b j ` u l u f p u a f h g m � w f � l ` � u u a f f h u f j u f � g b g b v j f m f b u h ` s � � d � a f | s ` � b p u a l ug b h ` m f v l h f h l j ` u l u g ` b ` s ` b w | � � v a l b q f p u a f b � m f j ` s s � b v u g ` b f l w � l u g ` b h |� � � � d � a f g j v ` b v w � h g ` b �

� a � h g u l � � f l j h u a l u u a f p f w g f j l u f v a ` g v f ` s l b g b g u g l w ` j g f b u l u g ` b a ` w p hl b f w f m f b u ` s j g h � s ` j l w w � u f j | j f q � w l j s � b v u g ` b h i p � f u ` u a f z g p f l j g l u g ` b h g b u a f b � m f j ` s j f � g j f p s � b v u g ` b f l w � l u g ` b h b f v f h h g u l u f p |f f b h m l w w v a l b q f h g b ` j g f b u l u g ` b d � a f p g � v � w u | g h v ` m � ` � b p f p | j l g h g b qu a f p g m f b h g ` b l w g u | ` s u a f ` � f v u g f s � b v u g ` b h g b v f u a g h z g p f b h u a f v a ` g v f` s ` j g f b u l u g ` b � l j l m f u f j h g b p g j f v u � j ` � ` j u g ` b d

Page 66: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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u g v f h ` s u a f ` j g q g b l w h g m � w f � f � h f p u ` l � � j ` � g m l u f u a f p g j f v u g ` b ` s h u f f � f h u p f h v f b u d� a g h g b s ` j m l u g ` b v ` � w p u a f b f � h f p u ` l p � � h u u a f ` j g f b u l u g ` b ` s u a f g b g u g l w h g m � w f �

h ` u a l u u a f g b g u g l w h u f � z ` � w p f l w ` b q u a g h l � � j ` � g m l u g ` b ` s u a f h u f f � f h u p f h v f b up g j f v u g ` b d � a f p g � v � w u | ` s u a g h l � � j ` l v a i l h u a f | b ` u f i g h u a l u u a f � l w g u | ` s u a g hf h u g m l u f p f � f b p h ` b u a f h v l w f ` s u a f g b g u g l w h g m � w f � d ~ f l p p u a l u u a g h l p � � h u m f b up f � f b p h ` b u a f v � j j f b u w ` v l w g b s ` j m l u g ` b l ` � u u a f s � b v u g ` b l b p u a � h g h w g � f w | u ` a l fw g u u w f g m � l v u ` b h � h f � f b u g u f j l u g ` b h d

� b s ` j u � b l u f w | i u a f h l m f p g � v � w u g f h � w l q � f u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m d� b s l v u i f v l � h f u a f h f u ` s h f l j v a p g j f v u g ` b h g h � b g u f i l b p � � f p | u a f v a ` g v f ` s u a f g b g �u g l w h g m � w f � i g u g h l w w u a f m ` j f ` g ` � h u a l u u a f ` j g f b u l u g ` b ` s u a f g b g u g l w h g m � w f � l ! f v u hu a f � f j s ` j m l b v f ` s u a f l w q ` j g u a m d � ` p l u f i z f a l f b ` u h � f b u m � v a u g m f l p p j f h h g b qu a g h � j ` w f m d x g b v f z f u | � g v l w w | � h f u a f � j ` v f p � j f h � q q f h u f p | _ l v ` | i f u l w d � � � � u `q f b f j l u f u a f g b g u g l w h g m � w f � s ` j ` � j u f h u � j ` w f m h i z f a l f b ` u j f l w w | f � � f j g m f b u f pz g u a v a l b q g b q u a f ` j g f b u l u g ` b ` s u a f h g m � w f � d � b f g p f l z f z ` � w p w g � f u ` � � j h � f g b �

` w f h j f h u l j u g b q u a f � j ` v f p � j f g s g u l � � f l j h u ` f m l � g b q w g u u w f � j ` q j f h h d � a f g p f l g hu ` � h f u a f s � b v u g ` b g b s ` j m l u g ` b l u f l v a ` s u a f f j u g v f h g b u a f h g m � w f � u ` v ` b h u j � v u l bl � � j ` � g m l u g ` b ` s u a f o f h h g l b l u u a f f h u f j u f � d � a f l � � j ` � g m l u g ` b u ` u a f o f h h g l bh a ` � w p l w w ` z � h u ` v ` b h u j � v u l j f l h ` b l w f � l p j l u g v m ` p f w ` s u a f � j ` w f m d ~ f v ` � w pu a f b q f b f j l u f l b f z h g m � w f � ` j g f b u f p l w ` b q u a f l � f h ` s u a f m ` p f w l b p j f h u l j u u a f� j ` w f m d ~ f u a g b � u a g h m l | � j ` f u ` f � h f s � w z a f b m g b g m g � g b q v ` m � w f � � j ` w f m h i � u z f a l f | f u u ` g m � w f m f b u u a g h � j ` v f p � j f d

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l w q ` j g u a m d y b | � l j u g v � w l j g b s ` j m l u g ` b l ` � u u a f s � b v u g ` b u ` f m g b g m g � f p m l | f� h f s � w g b a l h u f b g b q u a f � j ` q j f h h ` s u a f m f u a ` p d � a f ` b w | q f b f j l w h � q q f h u g ` b u a f u a f �

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h � m � u g ` b u a l u u ` f � � l b p u a f h g m � w f � z f p ` � w f u a f w f b q u a h ` s u a f f p q f h g b u a f h g m � w f �

z a g w f u ` v ` b u j l v u u a f h g m � w f � z f a l w f u a f w f b q u a h ` s l w w u a f f p q f h d � f u i g b u a f s ` j m l wh u l u f m f b u ` s u a f l w q ` j g u a m s ` � b p g b x f v u g ` b � d � i z f j f � g j f p ` b w | u a l u u a f f � � l b h g ` bs l v u ` j � f h u j g v u w | q j f l u f j u a l b ` b f z a g w f u a f v ` b u j l v u g ` b s l v u ` j � z l h j f � g j f p u ` f f u z f f b � l b p � d � a f v ` b f j q f b v f l b l w | h g h i g b � l j u g v � w l j u a f � j ` ` s ` s k w l g m � d � il p p f p u a f j f h u j g v u g ` b u a l u � l b p � f j l u g ` b l w b � m f j h h ` u a l u z f v ` � w p p f u f j m g b fu a f g j w f l h u v ` m m ` b p f b ` m g b l u ` j d x g b v f u a f m l v a g b f j f � j f h f b u l u g ` b ` s l b | j f l w b � m �

f j g h i g b s l v u i l j l u g ` b l w b � m f j i u a g h g h g b p f f p l f j | m g w p j f h u j g v u g ` b d x ` z a | p `z f v a ` ` h f � � � l b p � � �� �

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Page 68: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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g b l u g ` b h d � a f | v ` b v w � p f p u a l u u a f j f z l h b ` q f b f j l w h u j l u f q | z a g v a q l f u a f f h uj f h � w u h s ` j l w w u a f u f h u s � b v u g ` b h d � ` j u a f u f h u s � b v u g ` b h u a f | h u � p g f p � z a g v a z f j fl q l g b i s ` j u a f m ` h u � l j u i h m l w w i v ` m � w f � l b p w g m g u f p g b b � m f j � u l � g b q f � � l b h g ` bh u f � h ` s � �� l b p v ` b u j l v u g ` b h u f � h ` s �

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p f b u ` b u a f s � b v u g ` b u ` f m g b g m g � f p l h g h u a f v a ` g v f ` s u a f g b g u g l w h g m � w f � d � b s l v u iu a f u z ` v l b v w f l j w | g b u f j l v u d � a g h m l � f h u a f v a ` g v f ` s � ` � u g m l w h v l w g b q s l v u ` j h l w w � ug m � ` h h g w f d y q l g b i g s f � � f j g f b v f z g u a l v f j u l g b v w l h h ` s � j ` w f m h g b p g v l u f h u a l u l p g s �s f j f b u v a ` g v f ` s h v l w g b q s l v u ` j h q g f h f u u f j j f h � w u h i g u g h v f j u l g b w | j f l h ` b l w f u ` v a l b q fu a f h v l w g b q s l v u ` j h u ` j f � f v u u a g h g b s ` j m l u g ` b d � b q f b f j l w i u a ` � q a i u a f h g m � w g v g u | ` s� � � l b p � � �� g h � f j a l � h u a f f h u l j q � m f b u s ` j u a f g j v a ` g v f d

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~ f v ` � w p u a f b h l | u a l u u a f v � j j f b u h g m � w f � i l w ` b q z g u a g u h j f � f v u g ` b i � j ` g p f h � hz g u a l v j � p f � m ` p f w ` s u a f s � b v u g ` b l ` � u u a f v � j j f b u f h u f j u f � d ~ f u a f b � h fu a g h m ` p f w u ` p f u f j m g b f u a f h g � f ` s ` � j � j h u h u f � d � s u a g h h u f � � j ` p � v f h p f v j f l h f iz f l h h � m f u a l u ` � j m ` p f w m l | f u ` ` v ` b h f j l u g f i l b p u a � h p ` � w f u a f h g � f ` s u a fu j � h u j f q g ` b | p ` � w g b q u a f h g � f ` s u a f h g m � w f � d � b u a f ` u a f j a l b p i g s u a f � j h u h u f �p ` f h b ` u � j ` p � v f p f v j f l h f i z f v ` b v w � p f u a l u ` � j v � j j f b u m ` p f w g h b ` u u ` f u j � h u f p �

z f u a f b a l w f u a f h g � f ` s u a f u j � h u j f q g ` b | a l w g b q u a f w f b q u a h ` s u a f f p q f h g b u a fh g m � w f � d � a g h h g m � w f h u j l u f q | ` s f g u a f j p ` � w g b q ` j a l w g b q u a f j l p g � h ` s u a f u j � h uj f q g ` b a l h � j ` f b u ` f f j | f ! f v u g f s ` j u a f m ` p f w u j � h u j f q g ` b m f u a ` p h d ~ f a ` � fu a l u u a g h h l m f h g m � w f h u j l u f q | l w h ` � j ` f h u ` f f ! f v u g f s ` j u a f m � w u g � p g j f v u g ` b l wh f l j v a l w q ` j g u a m d

~ f v w ` h f z g u a ` b f � b l w v ` m m f b u l p p j f h h f p u ` u a ` h f z a ` l j f s l m g w g l j z g u a u a fn f w p f j � t f l p h g m � w f � l w q ` j g u a m d � a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m g b v w � p f h l h v l w fs l v u ` j s ` j u a f j f � f v u g ` b h u f � d � b u a f ` j g q g b l w f j h g ` b ` s ` � j l w q ` j g u a m z f l w h ` g b v w � p f pl h v l w g b q s l v u ` j � d ~ f j f � g j f p u a f h v l w g b q s l v u ` j h u ` h l u g h s | u a f s ` w w ` z g b q �

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u g ` b z f l v � g j f p l u u a f � j f g ` � h g u f j l u g ` b d � a � h i g u h f f m h f h u u ` h u l j u u a f v � j j f b ug u f j l u g ` b z g u a l h u f � ` s u a f h g � f u a l u z l h m ` h u h � v v f h h s � w g b u a f � j f g ` � h g u f j l u g ` b d� b v f z f a l f l v v � m � w l u f p l p p g u g ` b l w g b s ` j m l u g ` b l ` � u u a f s � b v u g ` b | u j | g b q u a fj f � f v u g ` b h u f � i z f u a f b p f v g p f a ` z u ` s � j u a f j m ` p g s | u a f h g � f ` s u a f h u f � h z f u l � f dx g b v f u a g h g m � w g f h u a l u � g h l w z l | h f � l w u ` ` b f i u a f j f g h b ` b f f p u ` g b v w � p f u a f l p p g �

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v g j v � m f b u ` u a ` s u a f p g � v � w u g f h a f g w w � h u j l u f p d � � j u a f j m ` j f i g b u a f m � w u g � p g j f v u g ` b l wh f l j v a l w q ` j g u a m i u a f w f b q u a ` s f l v a f p q f l p � l v f b u u ` u a f f h u f j u f � p f � b f h l j f w l u g fh u f � ` s w f b q u a � ` b f g b u a f p g j f v u g ` b p f u f j m g b f p | u a l u f p q f d � a � h i � h g b q � � d � � u `u f h u s ` j v ` b f j q f b v f g b u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m g h f � g l w f b u u ` u a f � h u f �u ` w f j l b v f u f h u � j ` � ` h f p | e f b b g h l b p x v a b l f w � � � � s ` j u a f � l h g � n f z u ` b m f u a ` p h d� a g h u f h u m f l h � j f h z a f u a f j u a f l w q ` j g u a m a l h q j ` � b p u ` l a l w u i f g u a f j f v l � h f g u a l hh u l w w f p ` j v ` b f j q f p i | g m � ` h g b q l m f l h � j f ` s u a f j f w l u g f v a l b q f g b u a f h � v v f h h g f l w � f h ` s � �� d e f b b g h l b p x v a b l f w l w h ` h � q q f h u f p l j f l h ` b l w f q � g p f w g b f s ` j v a ` ` h g b q� � g s � h g q b g � v l b u p g q g u h ` s � � l j f p f h g j f p i � h a ` � w p f h f u u ` � � � � d

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u � j b f p z l h i g b s l v u i l w ` v l w m g b g m g � f j ` s u a f s � b v u g ` b d � � j v ` b f j q f b v f l b l w | h g h w f p� h u ` f w g f f u a l u h � v a l v w l g m z l h � ` h h g w f s ` j u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m d� � j � f j s ` j m l b v f j f h � w u h z ` � w p h f f m u ` v ` b � j m u a g h v ` b � f v u � j f d ~ f l w h ` z l b u f p l bl w q ` j g u a m u a l u z ` � w p z ` j � z f w w z a f b u a f s � b v u g ` b l w � f h z f j f � b ` g h | i | z a g v a z fm f l b u a l u u a f s � b v u g ` b l w � f h l j f h � � f v u u ` f j j ` j d y q l g b i ` � j v ` b f j q f b v f l b l w | h g hh � q q f h u f p u a l u b ` g h f g b u a f s � b v u g ` b l w � f h z ` � w p b ` u a l f l p f u j g m f b u l w f ! f v u ` bu a f � j ` q j f h h ` s u a f h f l j v a � l b ` u a f j v ` b � f v u � j f z a g v a ` � j � f j s ` j m l b v f j f h � w u h z ` � w ph f f m u ` h � h u l g b d

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Page 76: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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g f b u a l u z f l j f b ` u g b u f j f h u f p g b u g m g b q j f h � w u h i � f j h f i z f p f v g p f p u ` � h f lp g ! f j f b u m f l h � j f ` s � f j s ` j m l b v f d x g b v f ` � j q ` l w g h u ` j f p � v f u a f u g m f h � f b u v ` m � � u g b qs � b v u g ` b l w � f h i z f v ` � b u f p u a f b � m f j ` s � � � � � � s � b v u g ` b f l w � l u g ` b h j f � g j f p u `j f u � j b l h ` w � u g ` b s ` j u a f h � f v g � f p u ` w f j l b v f w f f w l b p u a f b v ` b v ` v u f p l m f l h � j f ` su a f � � � � � � � � b � m f j ` s s � b v u g ` b f l w � l u g ` b h d � ` p f j g f u a g h m f l h � j f z f h g m � w | b ` u f pu a l u g s z f a l p u z f b u | � j ` v f h h ` j h i l b p u a f p g m f b h g ` b ` s u a f � j ` w f m z l h u a g j u | � u z ` iu a f b z f v ` � w p � f ! f v u g f w | v ` m � � u f l w w u a f s � b v u g ` b f l w � l u g ` b h g b u a f u g m f g u z ` � w pu l � f u ` v ` m � � u f u z ` s � b v u g ` b l w � f h ` b l h f � f b u g l w m l v a g b f d � a g h q g f h l b f ! f v u g fm f l h � j f ` s u z ` d � � j v � j j f b u g m � w f m f b u l u g ` b ` s u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a mm l � f h b ` l u u f m � u u ` l p p j f h h u a f g h h � f ` s w ` l p l w l b v g b q i u a ` � q a z f z g w w a l f m ` j fu ` h l | ` b u a g h h � � f v u w l u f j d � a f m l v a g b f z f � h f p u ` j � b ` � j u f h u h z l h l x f � f b ux | m m f u j | z g u a u z f b u | � j ` v f h h ` j h i � u z f v ` � w p � � h u l h f l h g w | a l f j � b ` � j u f h u h ` b

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z a f j f � g h l j l b p ` m b � m f j z g u a � b g s ` j m p g h u j g � u g ` b ` b � � � � � l b p � l b p � l j f� l j l m f u f j h h f u | u a f � h f j d � ` ` u l g b � z f � h f p u a f j l b p ` m b � m f j q f b f j l u ` j ` bu a f x f � f b u x | m m f u j | d � ` j u a f u f h u j f h � w u h z f z g w w h a ` z i � l b p � z f j f ` u a f � l w u `� d � � e � � � d

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y h z f b ` u f p g b k a l � u f j � i u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m l � u ` m l u g v l w w |j f h v l w f h u a f f b u g j f h g m � w f � g s g u g h f g u a f j u ` ` w l j q f ` j u ` ` h m l w w d � a f n f w p f j � t f l ph g m � w f � l w q ` j g u a m i a ` z f f j i ` b w | j f h v l w f h u a f f b u g j f h g m � w f � l h l w l h u j f h ` j u d � s b `g m � j ` f m f b u v l b f s ` � b p | u l � g b q l b | ` u a f j h u f � i u a f l w q ` j g u a m u l � f h l � h a j g b �

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g b l h a j g b � h u f � d � a � h i g s u a f g b g u g l w h g m � w f � g h u ` ` w l j q f i u a f n f w p f j � t f l p h g m � w f �

l w q ` j g u a m ` b w | v ` b u j l v u h ` b f f j u f � l u f l v a g u f j l u g ` b � l b p f l v a v ` b u j l v u g ` b j f h � w u hg b l p g h u ` j u g ` b ` s u a f g b g u g l w h g m � w f � d y h u a f p g m f b h g ` b ` s u a f � j ` w f m q j ` z h i j f h g � g b qu a f f b u g j f h g m � w f � j f � g j f h m ` j f l b p m ` j f g u f j l u g ` b h i f l v a ` s z a g v a g h v ` b p � v u f pg b p f � f b p f b u w | d y h l j f h � w u i u a f p g h u ` j u g ` b ` s u a f h g m � w f � g b v j f l h f h z g u a u a f p g m f b h g ` b` s u a f � j ` w f m d � a g h p g h u ` j u g ` b i g b u � j b i m f l b h u a l u g u g h f f j m ` j f w g � f w | u a l u u a fh f l j v a p g j f v u g ` b h z g w w p f u f j g ` j l u f d

� a g h v ` b � f v u � j f g h v ` b h g h u f b u z g u a ` h f j l u g ` b h m l p f | ` u a r l j � g b h ` b l b po � u v a g b h ` b � � � � l b p ~ l w m h w f | � � � � d r l j � g b h ` b l b p o � u v a g b h ` b i g b s l v u i h � q q f h u

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h u f � s � b v u g ` b u a f l b q w f f u z f f bu ` w f j l b v f � � � �

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{ | v ` b u j l h u i u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m i z a g w f h w ` z u ` v ` b f j q f i g h f j | j f w g l w f d k ` b h g p f j i s ` j f � l m � w f i g u h f a l g ` j ` b u a f f � u f b p f p � ` h f b j ` v � s � b v �

u g ` b l u u a f h l m f p g m f b h g ` b s ` j z a g v a u a f h f l j v a p f u f j g ` j l u f h g b u a f n f w p f j � t f l ph g m � w f � l w q ` j g u a m d � a f j f h � w u h l j f v ` b u l g b f p g b � l w f h � d � l b p � d d � a f f � u f b p f p� ` h f b j ` v � s � b v u g ` b i z a g v a g h l f j | a l j p � j ` w f m u ` h ` w f i p ` f h � j ` f u ` f p g � �

v � w u s ` j u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m d o ` z f f j i z a g w f u a f m � w u g � p g j f v u g ` b l wh f l j v a l w q ` j g u a m p ` f h j f � g j f ` u a h m l w w h u f � h l b p l q j f l u m l b | s � b v u g ` b f l w � l u g ` b hu ` j f l v a l h ` w � u g ` b i u a f � b l w l b h z f j j f u � j b f p | u a f l w q ` j g u a m � s ` j � � � d � � e � � � �g h v ` j j f v u u ` u a f h � l j f j ` ` u ` s m l v a g b f � j f v g h g ` b i z a g v a g h v f j u l g b w | l j f h � f v u l w fh a ` z g b q d � � j u a f j m ` j f i u a g h f a l g ` j g h v ` b h g h u f b u l v j ` h h l w w u a f v a ` g v f h ` s � s ` j z a g v az f u f h u f p u a f m f u a ` p ` b u a g h � j ` w f m i l h h a ` z b g b � l w f � d � � d

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s f v u s � b v u g ` b d y q l g b i z f w ` ` � l u u a f p g m f b h g ` b s ` j z a g v a u a f h f l j v a p g j f v u g ` b p f u f �

j g ` j l u f h g b u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m i l h h a ` z b g b � l w f h � d � l b p � d � � d � a f� b l w l b h z f j j f u � j b f p | u a f l w q ` j g u a m � s ` j � � � d � � e � � � � g h v ` j j f v u u ` m l v a g b f � j f �

v g h g ` b d � l w f � d � � h a ` z h u a l u u a g h f a l g ` j g h l q l g b v ` b h g h u f b u l v j ` h h l w w u a f v a ` g v f h` s � s ` j z a g v a z f u f h u f p u a f m f u a ` p ` b u a g h � j ` w f m d

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u s � b v u g ` b � � � g h u j g g l w u ` h ` w f � z g u a f � l v u j f � j f h f b u l u g ` b h s ` j u a f q j l p g f b u i ` u am f u a ` p h h ` w f u a f � j ` w f m g b ` b f h u f � d ~ g u a � b g u f p g ! f j f b v f l � � j ` � g m l u g ` b h u `u a f q j l p g f b u i ` u a m f u a ` p h j f � g j f u z ` g u f j l u g ` b h u ` h ` w f u a f � j ` w f m d ~ f g b v w � p f� l w f h � d � � l b p � d � � u ` h a ` z a ` z ` u a ` s u a f h f m f u a ` p h � f j s ` j m ` b u a f m ` j f p g � v � w uf � u f b p f p � ` h f b j ` v � s � b v u g ` b d � a f p g � v � w u | ` s u a f f � u f b p f p � ` h f b j ` v � s � b v u g ` bv l b f h f f b g b u a f s l v u u a l u u a f h u f f � f h u p f h v f b u m f u a ` p j f � g j f p ` f j � � � i � � � s � b v u g ` bf l w � l u g ` b h u ` v ` b f j q f u ` l h ` w � u g ` b i l w u a ` � q a u a g h g h h u g w w m � v a f u u f j u a l b u a f b � m �

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f j j f � g j f p s ` j u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m d � a f � l h g � n f z u ` b m f u a ` pp f m ` b h u j l u f p f j | v w f l j w | g u h v w l g m l h u a f u a ` j ` � q a j f p ` s ` � u g m g � l u g ` b m f u a ` p h d

� a f g b u f j f h u g b q � f h u g ` b u a f b f v ` m f h i z a l u a l � � f b h z a f b z f g b u j ` p � v f j l b p ` mb ` g h f g b u ` u a f s � b v u g ` b l w � f h u ` f f b � � u a f j l v f d y h z f a l f l w j f l p | b ` u f p i s ` ju a f h f u f h u h z f g b u j ` p � v f p f j j ` j ` b u a f ` j p f j ` s � d � � e � � � i z a g v a m f l b h u a l u z f h a ` � w pf � � f v u u a j f f h g q b g � v l b u p g q g u h g b u a f h ` w � u g ` b h j f u � j b f p | f l v a ` s u a f l w q ` j g u a m h d ~ fz g w w w g m g u ` � j p g h v � h h g ` b u ` u a f s � b v u g ` b � � � l b p h a ` z z a l u a l � � f b h s ` j f l v a ` s u a fs ` � j m f u a ` p h z a f b � � � � d

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y q l g b i u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m � j ` f p u ` f j ` � h u d � b � l w f � d � �

z f v l b h f f u a l u z f a l f l u w f l h u u a j f f h g q b g � v l b u p g q g u h g b u a f h ` w � u g ` b i j f q l j p w f h h ` su a f h u f � h g � f d t ` j f � j ` m g h g b q g h u a f s l v u u a l u z f b ` w ` b q f j h f f h g q b g � v l b u � � m � h g bu a f b � m f j ` s s � b v u g ` b v l w w h j f � g j f p u ` v ` b f j q f u ` l h ` w � u g ` b l h z f p f v j f l h f u a fh u f � h g � f d

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Page 95: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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y b ` u a f j ` h f j l u g ` b i l w h ` m l p f g b k a l � u f j � i g h u a l u u a f m � w u g � p g j f v u g ` b l w h f l j v al w q ` j g u a m � h f h l h u f � u ` w f j l b v f u f h u u ` p f u f j m g b f z a f u a f j ` j b ` u u ` h u ` � u a f h f l j v a d~ a g w f u a g h u f h u v f j u l g b w | z ` j � h i z f f w g f f u a l u z f h a ` � w p l w h ` g m � w f m f b u l b ` u a f ju f h u u a l u m l � f h � h f ` s u a f s � b v u g ` b g b s ` j m l u g ` b z f l v � g j f l u f l v a g u f j l u g ` b u ` p f v g p f

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Page 98: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 99: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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Page 100: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

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j g u a m d � a f j f l j f b � m f j ` � h p g j f v u g ` b h u ` f � � w ` j f d � g j h u i z f a l f ` b w | � � h u f q g bu ` f � � w ` j f u a f � ` u f b u g l w ` s u a f l w q ` j g u a m z a f b g m � w f m f b u f p ` b � l j l w w f w m l v a g b f h dx f v ` b p i z f a l f l z f l w u a ` s g p f l h u ` � � j h � f g b l b f ! ` j u u ` ` u a h � f f p � � u a f � j ` q j f h h` s u a f l w q ` j g u a m l b p u ` f � u f b p g u h l � � w g v l g w g u | d t l b | ` s u a f h f g m � j ` f m f b u h z f j fp g h v � h h f p g b k a l � u f j h � l b p � d ~ f l j f l w h ` g b u f j f h u f p g b u l v � w g b q m ` j f p g � v � w u � j ` �

w f m h � s ` j g b h u l b v f i � j ` w f m h z a f j f u a f s � b v u g ` b g h b ` u p g ! f j f b u g l w f d � a � h i z f a l fh f f j l w g p f l h s ` j p f l w g b q z g u a h � v a v l h f h d

� a f v ` b f j q f b v f u a f ` j f m s ` j u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m a l h h � q q f h u f ph f f j l w g b u f j f h u g b q j f h f l j v a p g j f v u g ` b h d � g j h u i z f f w g f f u a f v ` b f j q f b v f � j ` ` s v l b f m ` p g � f p u ` a l b p w f u a f v l h f z a f j f u a f s � b v u g ` b g h b ` u p g ! f j f b u g l w f d x f v ` b p i z f f w g f f u a l u u a f v ` b f j q f b v f j f h � w u v l b f p f f w ` � f p g b u ` l v ` b f j q f b v f u a f ` j | s ` j l b

Page 101: thesis - William & Maryva/research/thesis.pdfTitle: thesis.dvi Created Date: 8/14/2009 4:15:14 PM

f b u g j f v w l h h ` s p g j f v u h f l j v a l w q ` j g u a m h d ~ f f w g f f u a l u u a f h l m f ` h f j l u g ` b h u a l ua f w � f p � h g p f b u g s | � � � u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m s l g w h ` b w l j q f � j ` w f m hz g w w l w h ` a f w � � h p f u f j m g b f � � � u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a m s l g w h d � a g h g h ` sg b u f j f h u u ` � h h g b v f u a f l p l � u g f � j ` � f j u g f h ` s u a f n f w p f j � t f l p h g m � w f � l w q ` j g u a mv w f l j w | q g f g u l v ` m � f u g u g f f p q f ` f j u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m z a f bu a f p g m f b h g ` b ` s u a f � j ` w f m g h b ` m ` j f u a l b s ` � j d � s z f � b p f j h u ` ` p z a | u a f h f l j v a j f l � h p ` z b g b a g q a f j p g m f b h g ` b h i l b p v ` � w p g b h � j f u a l u u a g h j f l � p ` z b p g p b ` u ` v v � j iz f m g q a u f l w f u ` l p ` � u h ` m f ` s u a f h f � j ` � f j u g f h u ` h � f f p u a f � j ` q j f h h ` s u a f m � w u g �p g m f b h g ` b l w h f l j v a l w q ` j g u a m d � g b l w w | i u a f v ` b f j q f b v f u a f ` j f m p f m ` b h u j l u f p u a l uu a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m f b s ` j v f h h u f � w f b q u a v ` b u j ` w z g u a ` � u j f h ` j u g b qu ` u a f y j m g � ` � ` w p h u f g b � ~ ` w s f v ` b p g u g ` b h d ~ f z ` � w p w g � f u ` � b p f j h u l b p ` u a z a | u a g hg h h ` l b p a ` z g u j f w l u f h u ` u a f f � g h u g b q u a f ` j | s ` j ` u a f j � b v ` b h u j l g b f p ` � u g m g � l u g ` bm f u a ` p h d

~ f z g w w b ` z p g h v � h h h f f j l w ` s u a f h f u ` � g v h g b s � j u a f j p f u l g w

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l w w f w � u a f w ` ` � u ` g b g u g l w g � f u a f � j ` v f p � j f l b p u a f u a j f f w ` ` � h s ` j f l v a ` s u a f j f � f v u g ` b if � � l b h g ` b i l b p v ` b u j l v u g ` b h u f � h d � x f f u a f s ` j m l w h u l u f m f b u ` s u a f l w q ` j g u a m q g f bg b x f v u g ` b � d � d � ~ f a l f b ` u | f u l p p j f h h f p u a f g h h � f ` s w ` l p l w l b v g b q d x ` s l j z fa l f g q b ` j f p � j ` v f h h ` j h u a l u m l | f g p w f p � j g b q u a f v ` � j h f ` s u a f v ` m � � u l u g ` b i l h ` � jj f h � w u h g b k a l � u f j � h a ` � w p m l � f v w f l j d � a f � j ` ` s ` s ` � j v ` b f j q f b v f u a f ` j f m i a ` z �

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f f j i a l h q g f b � h h f f j l w g p f l h s ` j g m � j ` g b q u a f � f j s ` j m l b v f ` s u a f m � w u g � p g j f v u g ` b l wh f l j v a l w q ` j g u a m ` b � l j l w w f w m l v a g b f h d

� f u � j b g b q u ` u a f v ` b f j q f b v f u a f ` j f m i b ` u f u a l u z f ` b w | j f � g j f � � � � � p f v j f l h f �

u a f s � b v u g ` b l w � f ` s � � � ` s u a f b f z f j u g v f h m � h u f f u u f j u a l b u a f s � b v u g ` b l w � fl u u a f f h u f j u f � d ~ f h | h u f m l u g v l w w | h f l j v a g b � w g b f l j w | g b p f � f b p f b u p g j f v u g ` b h f v l � h f g s � g h p g ! f j f b u g l w f i ` b f ` s u a f h f h f l j v a p g j f v u g ` b h g h q � l j l b u f f p u ` � j ` p � v f lp g j f v u g ` b ` s p f h v f b u d o ` z f f j i l h h ` ` b l h u a f l w q ` j g u a m g p f b u g � f h l f j u f � u a l u a l h ls � b v u g ` b l w � f u a l u g h f u u f j u a l b u a f s � b v u g ` b l w � f l u u a f f h u f j u f � i u a f h f l j v a v l b f h u ` � � f p d � a g h ` h f j l u g ` b a l h w f p � h u ` u a f s ` w w ` z g b q w ` l p l w l b v g b q h u j l u f q g f h iq g f b � l l g w l w f � j ` v f h h ` j h �

� g j h u i l h h � m f u a l u � � � d { f q g b u a f g u f j l u g ` b | h f l j v a g b q g b � p g j f v u g ` b h d � s ` b f` s u a f f j u g v f h j f u � j b h l s � b v u g ` b l w � f u a l u g h f u u f j u a l b u a f s � b v u g ` b l w � f l u u a f f h u f j u f � i u a f b u a f l w q ` j g u a m v l b h u ` � u a f h f l j v a i � � p l u f l w w j f w f l b u g b s ` j m l u g ` bl b p q ` ` b u ` u a f b f � u g u f j l u g ` b � u a f j f g h b ` b f f p u ` h f l j v a g b l w w � p g j f v u g ` b h d � sb ` b f ` s u a f � u j g l w f j u g v f h v l b j f � w l v f u a f v � j j f b u f h u f j u f � i v a ` ` h f � m ` j f h f l j v ap g j f v u g ` b h s j ` m u a f h f u ` s � h f l j v a p g j f v u g ` b h d � a f h f l j v a v ` b u g b � f h g b u a g h z l | � b u g wf g u a f j u a f f h u f j u f � g h j f � w l v f p i ` j l w w � h f l j v a p g j f v u g ` b h a l f f f b v ` b h g p f j f p dk w f l j w | h ` m f v l j f m � h u f u l � f b g b v a ` ` h g b q u a f ` j p f j g b z a g v a u a f � � ` h h g w f h f l j v ap g j f v u g ` b h l j f v ` b h g p f j f p d � p f l w w | i z f z ` � w p w g � f u ` w g m g u u a f h f l j v a u ` u a f � j h u �

p g j f v u g ` b h v ` b h g p f j f p l u f l v a g u f j l u g ` b i � u z f m � h u l w h ` f v l j f s � w u ` v | v w f u a j ` � q au a f p g j f v u g ` b h h ` u a l u u a f l w q ` j g u a m p ` f h b ` u h g m � w | m g b g m g � f ` f j l h � h � l v f d � b fg m � ` j u l b u � ` g b u u ` m l � f g h u a l u g s z f v l b � b p j f l h ` b l w f h u j l u f q g f h s ` j p f u f j m g b g b qu a f ` j p f j ` s u a f h f l j v a p g j f v u g ` b h i z f m l | a l f l b l w q ` j g u a m u a l u g h l w h ` � h f s � w ` b� � � � � � � � � � m l v a g b f h � � h g m � w | f � l w h ` b f d

� a f j f g h h u g w w u a f � ` h h g g w g u | u a l u z f m � h u h f l j v a g b l w w � p g j f v u g ` b h i l b p u a l u� � m ` p � � �� � d � a g h g h h g m g w l j u ` u a f h g u � l u g ` b z f s l v f z a f b � � � d ~ f f w g f f

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l v l j f s � w � h f ` s u a f � h � f v � w l u g f s � b v u g ` b f l w � l u g ` b l � � j ` l v a m l | a f w � ` f j v ` m fu a g h h a ` j u v ` m g b q d � a f � h � f v � w l u g f s � b v u g ` b f l w � l u g ` b l � � j ` l v a u ` w ` l p l w l b v g b ql p ` v l u f h u a f v l w v � w l u g ` b ` s s � b v u g ` b l w � f h f s ` j f g u g h v w f l j u a l u u a f | z g w w f j f � g j f p ih ` u a l u u a f | l j f l w j f l p | l l g w l w f h a ` � w p u a f | f b f f p f p d

� � j � h f ` s h � f v � w l u g f s � b v u g ` b f l w � l u g ` b g h l h f p ` b u a f ` h f j l u g ` b i � j h u m l p fg b k a l � u f j � i u a l u q g f b l b g b g u g l w h g m � w f � z f v l b � j f p g v u l � j g ` j g u a f � ` g b u h z a g v au a f l w q ` j g u a m m g q a u g h g u � b ` u ` b w | s ` j u a f v � j j f b u g u f j l u g ` b i � u g b h � h f � f b ug u f j l u g ` b h l h z f w w d ~ f p f m ` b h u j l u f p u a g h � j ` v f h h g b � g q � j f h � d � � � d � d ~ f m � h u fv l j f s � w u ` b ` u f i a ` z f f j i u a l u s ` j u a f h l � f ` s u a f v ` b f j q f b v f � j ` ` s z f l h h � m f p u a l uu a f j f f � g h u h l w ` z f j ` � b p ` b u a f w f b q u a ` s u a f f p q f h g b u a f h g m � w f � z a f b i g b s l v u ib ` h � v a ` � b p f � g h u h d ~ f v l b i b ` b f u a f w f h h i � j f p g v u g b l p l b v f u a f � ` g b u h u a l u z g w w f g h g u f p g b h � h f � f b u g u f j l u g ` b h d n ` z i a ` z f f j i u a f b � m f j ` s � ` g b u h g b u a f q j g pg h v ` � b u l w | g b � b g u f i j l u a f j u a l b � b g u f i f v l � h f z f b ` w ` b q f j a l f l � � f p m f h a h g � f d

� ` g b h � j f w ` l p l w l b v g b q z a f b f g u a f j � � m ` p � � �� � ` j � � � i z f l b u g v g � l u fu a f � ` g b u h u a l u u a f l w q ` j g u a m g h w g � f w | u ` g h g u b f � u l b p � h f l w w � f � u j l � j ` v f h h ` j hu ` v ` m � � u f u a f s � b v u g ` b l w � f h l u h ` m f h � h f u ` s u a f h f � ` g b u h d ~ f � w l b u ` p f f w ` �h u j l u f q g f h u ` p f v g p f z a g v a � ` g b u h h a ` � w p f v ` b h g p f j f p � j h u d

� z ` j f m l j � h h a ` � w p f m l p f a f j f d � g j h u i z f p ` b ` u b f f p l b f � � w g v g u j f � j f h f b u l u g ` b` s u a f q j l p g f b u f g u a f j u ` p f u f j m g b f l h f l j v a p g j f v u g ` b ` j u ` p f v g p f g s z f a l f h l u g h � f p l� � � � � � � � p f v j f l h f v ` b p g u g ` b d � a f h f u ` s h f l j v a p g j f v u g ` b h g h p f u f j m g b f p | u a f g b g u g l wh g m � w f � l b p u a f l w q ` j g u a m ` b w | j f � g j f h � � � � � p f v j f l h f g b u a f s � b v u g ` b l w � f l u u a f f h u f j u f � d � a � h i z f p ` b ` u j f � g j f � � � � s � b v u g ` b f l w � l u g ` b h l u f l v a g u f j l u g ` b f s ` j f z f v l b f q g b u a f h f l j v a d x f v ` b p i � j f v g h f w | f v l � h f z f v l b � j f p g v u l w w u a f� ` g b u h u a f l w q ` j g u a m m g q a u v ` b h g p f j i z f v l b � h u l j u u a f b f � u g u f j l u g ` b f s ` j f z f a l fl v u � l w w | � b g h a f p u a f v � j j f b u g u f j l u g ` b d � a � h i z f v l b p f f w ` � h u j l u f q g f h u a l u � h f � � � �

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s � b v u g ` b f l w � l u g ` b h l u f l v a g u f j l u g ` b i z a g v a m f l b h u a l u z f h a ` � w p f l w f u ` m l � f f u u f j � h f ` s � l j l w w f w m l v a g b f h d

� a f s l v u u a l u u a f l w q ` j g u a m ` b w | j f � g j f h h g m � w f p f v j f l h f w f l p h � h u ` ` b f � b l w w ` l p l w l b v g b q g h h � f d � h � l w w | z f l h h � m f u a l u l w w s � b v u g ` b f l w � l u g ` b j ` � u g b f h j f � g j f u a fh l m f l m ` � b u ` s u g m f u ` v ` m � � u f u a f s � b v u g ` b l w � f d � ` j u a f u f h u � j ` w f m h z f � h f pg b k a l � u f j � u a g h z l h v f j u l g b w | l j f l h ` b l w f l h h � m � u g ` b l b p u a � h m l p f ` � j m f l h � j f` s � f ! f v u g f s � b v u g ` b f l w � l u g ` b h l w g p d o ` z f f j i u a f � j ` w f m h z f l j f � w u g m l u f w |g b u f j f h u f p g b h ` w g b q ` s u f b g b ` w f g u f j l u g f � j ` v f p � j f h � h � v a l h u a f h ` w � u g ` b ` s l b` j p g b l j | p g ! f j f b u g l w f � l u g ` b d � a g h m f l b h u a l u u a f u g m f j f � g j f p s ` j f l v a s � b v u g ` bf l w � l u g ` b v ` � w p l j | u j f m f b p ` � h w | d o ` z f f j i h g b v f z f ` b w | j f � g j f h g m � w f p f v j f l h f iz a g v a b f f p b ` u b f v f h h l j g w | f u a f q j f l u f h u p f v j f l h f i l h h ` ` b l h z f a l f s ` � b p lj f � w l v f m f b u s ` j � �� z f v l b h u ` � u a f v ` m � � u l u g ` b l b p � j ` v f f p g m m f p g l u f w | u ` u a fb f � u g u f j l u g ` b d y q l g b i u a g h h a ` � w p w f l p u ` f u u f j ` f j l w w � h f ` s u a f l l g w l w f � j ` v f h h g b q� ` z f j d

� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �

~ f l j f g b u f j f h u f p g b � b p g b q z l | h u ` a l b p w f � j ` w f m h u a l u p ` b ` u h l u g h s | u a f l h h � m � �

u g ` b h j f � g j f p s ` j ` � j u a f ` j f u g v l w j f h � w u h d � s z f j f w l � u a f p g ! f j f b u g l g w g u | l h h � m � u g ` b iu a f l w q ` j g u a m m g q a u q f u u j l � � f p g b � l p p g j f v u g ` b h � g d f d i g u m g q a u b ` u � b p l p f h v f b up g j f v u g ` b d ~ a f b u a f s � b v u g ` b g h b ` u v ` b f � i u a f l w q ` j g u a m m l | h u g w w v ` b f j q f u ` lh u l u g ` b l j | � ` g b u i � u u a f h u l u g ` b l j | � ` g b u m l | f l h l p p w f � ` g b u j l u a f j u a l b l m g b g �m g � f j d � b ` u a v l h f h i u a f m f u a ` p g h a l m � f j f p | u a f v a ` g v f ` s u a f h u l j u g b q h g m � w f � dy h z f a l f m l p f v w f l j i u a f v a ` g v f ` s u a f g b g u g l w h g m � w f � z g w w a l f l � j ` s ` � b p f ! f v u ` bu a f � f j s ` j m l b v f ` s u a f l w q ` j g u a m i h g b v f u a f h f l j v a p g j f v u g ` b h l j f v a ` h f b s j ` m l � b g u fh f u ` s � � f p h f l j v a p g j f v u g ` b h p f u f j m g b f p | u a f h g m � w f � � h f p u ` h u l j u u a f � j ` v f p � j f dx g b v f h ` m f g m � ` j u l b u � j ` w f m h l j f b ` u p g ! f j f b u g l w f ` j b ` u v ` b f � i z f z ` � w p w g � f

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u ` p f f w ` � � j l v u g v l w l w u f j b l u g f h s ` j ` f j v ` m g b q l b � b s ` j u � b l u f v a ` g v f ` s l h u l j u g b qh g m � w f � d

e g ! f j f b u g l g w g u | v w f l j w | � w l | h l � f | j ` w f d ~ f a l f s ` � b p h g m � w f f � l m � w f h s ` j z a g v au a f l w q ` j g u a m v ` b f j q f h u ` l � ` g b u u a l u g h b ` u l w ` v l w m g b g m g � f j � u l u z a g v a u a f s � b v �

u g ` b g h b ` u p g ! f j f b u g l w f d y h h � m f u a f f h u f j u f � � �� g h l u l � ` g b u z a f j f u a f s � b v u g ` bg h b ` u p g ! f j f b u g l w f d � a f b i f f b g s u a f � h f l j v a p g j f v u g ` b h l j f w g b f l j w | g b p f � f b p f b uz f v l b b ` u f v f j u l g b u a l u l u w f l h u ` b f ` s u a f f p q f h g p f b u g � f h l p g j f v u g ` b ` s p f h v f b u d� a f h f l j v a m g q a u u a f b f � h u � v � l b p u a f l b h z f j j f u � j b f p | u a f l w q ` j g u a m m l | f � �� d � s � �� g h b ` u l m g b g m g � f j i u a f j f l j f p g j f v u g ` b h s ` j z a g v a p f h v f b u g h q � l j l b u f f p d� a f � j ` w f m g h u a l u u a f l w q ` j g u a m p g p b ` u g p f b u g s | ` b f ` s u a f h f p g j f v u g ` b h d � a f h l m fh ` j u ` s p g � v � w u | v l b ` v v � j z a f b u a f s � b v u g ` b g h b ` u v ` b f � d ~ f a l f v ` b h u j � v u f pl b f � l m � w f g b z a g v a u a f f h u f j u f � � �� g h l h l p p w f � ` g b u l b p b ` b f ` s u a f h f l j v ap g j f v u g ` b h w g f g b l p g j f v u g ` b ` s b f q l u g f v � j l u � j f d y q l g b u a f h f l j v a g h h u � v � l b p u a fl b h z f j j f u � j b f p | u a f l w q ` j g u a m z g w w f � �� i z a g v a g h l h u l u g ` b l j | � ` g b u � u b ` u lm g b g m g � f j ` s u a f s � b v u g ` b d ~ f z ` � w p w g � f u ` f l w f u ` j f v ` f j g b h � v a g b h u l b v f h |l � u ` m l u g v l w w | q f b f j l u g b q l b f z h g m � w f � u ` q g f l b f z h f u ` s h f l j v a p g j f v u g ` b h d c g u a f j� h g p f h u f � � g b q ` j f h u g m l u g b q v � j l u � j f g b s ` j m l u g ` b m l | a f w � q f b f j l u f b f z h g m � w g v f h il b p u a � h b f z h f u h ` s h f l j v a p g j f v u g ` b h i z a f b u a f h f p g � v � w u g f h l j f f b v ` � b u f j f p d

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p g m f b h g ` b l w � l � b f � h � h � l v f p f � b f p | u a f s l v f ` s u a f h g m � w f � u a l u g b v w � p f h l w w � uu a f f h u f j u f � d � a f b f z s l v f j f u � j b f p | u a g h h u f � z ` � w p u a f b j f � w l v f u a f ` b f g bu a f ` j g q g b l w h g m � w f � d � a g h z ` � w p v a l b q f u a f ` j g q g b l w h a l � f ` s u a f h g m � w f � i � u g uz ` � w p l w h ` q g f u a f � j ` v f p � j f l b f z h f u ` s h f l j v a p g j f v u g ` b h d x g p f h u f � � g b q l � � f l j h

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u ` � j f h f j f ` b f ` s u a f g m � ` j u l b u s f l u � j f h u a l u l w w ` z h � h u ` � j ` f v ` b f j q f b v f s ` ju a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m d ~ f z ` � w p w g � f u ` h f f g s u a g h f � u f b h g ` b v l b fg b v w � p f p g b ` � j f � g h u g b q v ` b f j q f b v f u a f ` j | d ~ f z ` � w p l w h ` w g � f u ` h f f a ` z z f w w u a g hg p f l � f j s ` j m h g b � j l v u g v f d

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j g u a m g m � w g v g u w | l � � j ` � g m l u f h u a f q j l p g f b u d ~ a g w f u a f l w q ` j g u a m p ` f h b ` u f � � w g v g u w |v ` m � � u f � b g u f p g ! f j f b v f l � � j ` � g m l u g ` b h u ` u a f q j l p g f b u i u a f l w q ` j g u a m g b h u f l p v ` b �

h g p f j h l b l u � j l w l w u f j b l u g f � l u f f j | g u f j l u g ` b g u f � � w ` j f h f l v a p g j f v u g ` b g b l h f u ` s� w g b f l j w | g b p f � f b p f b u h f l j v a p g j f v u g ` b h d � a f m � w u g � p g j f v u g ` b l w h f l j v a v ` � w p u a f b f g f z f p l h l b g m � w g v g u � b g u f p g ! f j f b v f l � � j ` � g m l u g ` b i g b l p g ! f j f b u l h g h i u ` u a f q j l �

p g f b u d � a f � j ` w f m i � l j u g v � w l j w | z a f b p f l w g b q z g u a s � b v u g ` b h u a l u l j f b ` u v ` b f � ig h u a l u u a f l w q ` j g u a m p ` f h b ` u a l f l b | v � j l u � j f g b s ` j m l u g ` b d � ` ` f j v ` m f u a g hp g � v � w u | i z f z ` � w p w g � f u ` l � � j ` � g m l u f v � j l u � j f g b s ` j m l u g ` b l u u a f � ` g b u j f u � j b f p | u a f l w q ` j g u a m d � a g h g h h � f a l h l w j f l p | f f b v ` b h g p f j f p ` u a | x � f b p w f | i o f � u il b p o g m h z ` j u a � � � � l b p | n f w p f j l b p t f l p � � � � d � a f h f j f h f l j v a f j h z f j f g b u f j f h u f pg b v ` b h u j � v u g b q u a f o f h h g l b m l u j g � l u u a f m g b g m g � f j g b ` j p f j u ` � j ` p � v f u a f l j g l b v f �

v ` l j g l b v f m l u j g � ` s u a f f h u g m l u f h d ~ f l j f g b u f j f h u f p g b � � j h � g b q u a g h g p f l f v l � h fz f u a g b � z f v l b � h f v � j l u � j f g b s ` j m l u g ` b u ` v ` b h u j � v u l � u ` m l u g v j f h u l j u h u j l u f q g f h d� b f � ` h h g g w g u | z ` � w p f u ` � h f u a f o f h h g l b u ` v ` b h u j � v u l b f z h g m � w f � z g u a u a f f p q f h` j g f b u f p l w ` b q u a f l � f h ` s l � l p j l u g v m ` p f w ` s u a f s � b v u g ` b d � a g h z ` � w p p f u f j m g b fl b f z h f u ` s h f l j v a p g j f v u g ` b h d � p f l w w | i u a f h f h f l j v a p g j f v u g ` b h z ` � w p f u u f j h � g u u a f� l j u g v � w l j � j ` w f m d

c h u g m l u g b q v � j l u � j f g b s ` j m l u g ` b z ` � w p l w h ` l w w ` z � h u ` f � � w ` j f l p g ! f j f b u l � � w g �v l u g ` b ` s u a f � l j l w w f w l w q ` j g u a m d � s z f v l b s � j b g h a l b l � � j ` � g m l u g ` b u ` u a f o f h h g l b i

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z f v l b h u l j u l n f z u ` b � w g � f � j ` v f p � j f d � a g h h � q q f h u h l b g b u f j f h u g b q u g f u ` z ` j � f �

q g b p ` b f ` b g b f j h f � j ` w f m h | ~ g w w g l m h ` b � � � � � h g b v f u a f m � w u g � p g j f v u g ` b l w h f l j v al w q ` j g u a m p ` f h b ` u j f � g j f l q j f l u p f l w ` s l v v � j l v | g b u a f s � b v u g ` b f l w � l u g ` b h i g uv ` � w p f � h f p l h u a f � j h u h u l q f g b l b l � � j ` l v a u ` h ` w g b q g b f j h f � j ` w f m h d � b v f u a fm � w u g � p g j f v u g ` b l w h f l j v a a l h g p f b u g � f p u a f b f g q a ` j a ` ` p ` s l h ` w � u g ` b i u a f h f l j v a v ` � w pu a f b h z g u v a u ` u a f n f z u ` b � w g � f m f u a ` p h p f f w ` � f p s ` j g b f j h f � j ` w f m h d � a f � l j l w �w f w p g j f v u h f l j v a l w q ` j g u a m a l h u a f l p l b u l q f ` s f g b q j f w l u g f w | g b f � � f b h g f � u u a fn f z u ` b � w g � f m f u a ` p h a l f s l h u w ` v l w v ` b f j q f b v f � j ` � f j u g f h d � a g h h v a f m f g h p f h g q b f pu ` f � � w ` g u ` u a ` s u a f h f l p l b u l q f h d

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~ f v ` � w p g f z u a f h g m � w f � � h f p g b u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m l h u a f� � l u u f j b � h f p u ` q f b f j l u f ` u a u a f p g j f v u g ` b h ` s h f l j v a l b p u a f h g � f ` s u a f h u f � h d� u a f j m f u a ` p h g b u a g h v w l h h h g m � w | � h f ` u a f j � � l u u f j b h u ` p f u f j m g b f u a f p g j f v u g ` b h` s h f l j v a l b p u a f h g � f ` s u a f h u f � h i � u u a f h u j � v u � j f � b p f j w | g b q u a f h f m f u a ` p h g h u a fh l m f d ~ f u a � h f w g f f z f v l b p f f w ` � l q f b f j l w v ` b f j q f b v f u a f ` j | s ` j u a g h v w l h h ` sp g j f v u h f l j v a m f u a ` p h i z g u a ` � u m ` p g s | g b q u a f h f l w q ` j g u a m h d ~ f � b ` z ` s b ` f � g l w f b uv ` b f j q f b v f u a f ` j | s ` j u a g h v w l h h ` s p g j f v u h f l j v a m f u a ` p h d ~ f a l f j f v f b u w | f v ` m f

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l z l j f ` s l h g m g w l j f ! ` j u | ~ f b � v g � � � � i � � � � d o ` z f f j i a g h v ` b f j q f b v f l b l w | h g hj f � g j f h l b ` u g ` b ` s h � � v g f b u p f v j f l h f z a g v a g u g h b ` u v w f l j v l b f g m � w f m f b u f p g b� j l v u g v f d o g h u a f ` j | l w h ` v l b b ` u f f � u f b p f p u ` v ` f j u a f m � w u g � p g j f v u g ` b l w h f l j v al w q ` j g u a m f v l � h f g u j f � g j f h u a f h u f � h g � f u ` f m ` b ` u ` b g v l w w | p f v j f l h g b q i z a g v ap ` f h b ` u a ` w p s ` j u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m g s f � � l b h g ` b h u f � h l j f l w w ` z f p d� b u a f ` u a f j a l b p i g u l � � f l j h u a l u ` � j v ` b f j q f b v f u a f ` j | v l b f f � u f b p f p u ` u a f l j g l b u h ~ f b � v g � j ` � ` h f h s ` j ` u a u a f � l u u f j b h f l j v a l w q ` j g u a m ` s o ` ` � f l b p _ f f f hl b p u a f ` j g q g b l w h g m � w f � m f u a ` p ` s x � f b p w f | i o f � u i l b p o g m h z ` j u a d k �f l � � � � l w h `q g f h l v ` b f j q f b v f j f h � w u s ` j l l j g l b u ` s u a f � l u u f j b h f l j v a l w q ` j g u a m ` s o ` ` � f l b p_ f f f h i � u a f j f � g j f h u a l u u a f h u f � h g � f h f h u j g v u w | m ` b ` u ` b g v l w w | p f v j f l h g b q l uf f j | g u f j l u g ` b � l m ` p g � v l u g ` b z f f w g f f z ` � w p f � b h l u g h s l v u ` j | g b � j l v u g v f d

� g b l w w | i z f f w g f f u a l u u a f v ` b f j q f b v f u a f ` j f m v l b f f � u f b p f p u ` v ` f j u a fb ` b � p g ! f j f b u g l w f v l h f d � b h u f l p ` s v ` b f j q f b v f u ` l h u l u g ` b l j | � ` g b u i z f m l | f l w fu ` h a ` z v ` b f j q f b v f u ` l v j g u g v l w � ` g b u i z g u a s f z m l � ` j m ` p g � v l u g ` b h ` s u a f � j ` ` s d

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g b g h v f b u ` s u a f h u f � h g � f j � w f ` s u a f u j � h u j f q g ` b m f u a ` p h d { ` u a m f u a ` p h ` b w | j f �

� g j f h g m � w f p f v j f l h f ` b u a f l w � f ` s u a f ` � f v u g f s � b v u g ` b � b f g u a f j j f � g j f h u a l uu a f y j m g � ` � ` w p h u f g b � ~ ` w s f v ` b p g u g ` b h f h l u g h � f p d { ` u a m f u a ` p h f m � w ` | l h g m � w f l v � u j l v � g b q h u j l u f q | u ` f b h � j f u a l u u a f h u f � g h b ` u u ` ` h a ` j u � h u f � h l j f u | � g v l w w |a l w f p i � u ` b w | � b u g w l � ` g b u u a l u � j ` p � v f h p f v j f l h f g b u a f ` � f v u g f s � b v u g ` b l w � fg h s ` � b p d n f g u a f j m f u a ` p h l s f q � l j p h l q l g b h u u l � g b q l h u f � u a l u g h u ` ` w ` b q j f w l u g fu ` u a f l m ` � b u ` s p f v j f l h f g b u a f ` � f v u g f s � b v u g ` b � u a f ` u a f j a l w s ` s u a f y j m g � ` �

` w p h u f g b � ~ ` w s f v ` b p g u g ` b h � l b p | f u g b b f g u a f j v l h f g h u a g h v ` b p g u g ` b b f v f h h l j | u `

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� j ` f v ` b f j q f b v f d � a g h g h m l j � f p w | p g ! f j f b u s j ` m u a f h u l b p l j p v ` b f j q f b v f j f h � w u hs ` j w g b f h f l j v a m f u a ` p h d ~ f z ` � w p w g � f u ` f � � w ` j f u a f j f w l u g ` b h a g � f u z f f b u a f h u f �h g � f j � w f s ` j u a f m � w u g � p g j f v u g ` b l w h f l j v a l w q ` j g u a m l b p u a f h u f � h g � f j � w f s ` j u a f u j � h uj f q g ` b m f u a ` p h u ` h f f z a l u s f l u � j f h u a f | m l | h a l j f d � a f l b h z f j m l | h a f p b f z w g q a u` b u a f z l | z f g f z w g b f h f l j v a f h d

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� � � t d _ d { ` � d y v ` m � l j g h ` b ` s h f f j l w v � j j f b u ` � u g m g � l u g ` b m f u a ` p h i l b p u a f � h f` s u j l b h s ` j m l u g ` b h g b v ` b h u j l g b f p � j ` w f m h d � � � � � � � � � � � � � � � � � i � � � � � � � � � it l | � � � d

� � � t d _ d { ` � i e d e l g f h i l b p ~ d o d x z l b b d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � d� k � t ` b ` q j l � a n ` d � d � w g f j � { ` | p i c p g b � j q a i � � d

� � � j f q ` j | � d { j g h h f | i � ` f j u { d x � f b v f j i l b p k a l j w f h � d ~ g w � g b h d o g q a � h � f f p l w q ` �

j g u a m s ` j h g m � w f � ` � u g m g � l u g ` b v l w v � w l u g ` b h d � � � � � � � � � � � � � � � � � � i � � � � � � � � � � �

� � � i n ` f m f j � � d

� � � x l m � f w o d { j ` ` � h l b p t d � l | t g v � f | d � � u g m � m f h u g m l u g ` b ` s q j l p g f b u p g j f v u g ` bg b h u f f � f h u l h v f b u f � � f j g m f b u h d � � � � � � � � i � � � � � � � � i t l j v a � � � d

� � � } d ~ d k d { � j u ` b l b p d n g v � w f h h d � � u g m g h l u g ` b g l h g m � w f � � r l j u g d l v � q j ` � b p ip f � b g u g ` b h l b p l h g m � w f l � � w g v l u g ` b d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �� � � � � � i � � � � � � � � i � � � d

� � � � d o d { | j p i � d { d x v a b l f w i l b p d y d x a � w u � d � h g b q � l j l w w f w s � b v u g ` b f l � w l u g ` b hu ` g m � j ` f o f h h g l b l � � j ` � g m l u g ` b h s ` j � b v ` b h u j l g b f p ` � u g m g � l u g ` b d � f v a b g v l w� f � ` j u k x � k � � � � � � � � i � b g f j h g u | ` s k ` w ` j l p ` i � � � d

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� � � d o d { | j p i � d { d x v a b l f w i l b p d y d x a � w u � d r l j l w w f w � l h g � n f z u ` b m f u a ` p hs ` j � b v ` b h u j l g b f p ` � u g m g � l u g ` b d � f v a b g v l w � f � ` j u k � � k x � � � � � � i � b g f j h g u | ` sk ` w ` j l p ` i � � � d

� � � � _ f l b k �f l d � � � � � � � � � � � � � �� � � � � � � � � � � � � � � � � d e � b ` p i r l j g h i � � � d

� � � � e d o d k a f b i � d x l w f f m i l b p e d ~ d j l v f d y b f z h g m � w f � � j ` v f p � j f s ` j s � b v �

u g ` b m g b g m g � l u g ` b d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � i � � � � � � � � � � i� � � d

� � � � � a ` m l h � d k ` w f m l b l b p � l b q | f � g d x ` w g b q h | h u f m h ` s b ` b w g b f l j f � l u g ` b h` b l m f h h l q f � � l h h g b q m � w u g � j ` v f h h ` j d � f v a b g v l w � f � ` j u k � � � � � � � i � l v � w u | ` st l u a f m l u g v h i � b g f j h g u | ` s ~ l u f j w ` ` i e f v f m f j � � � d

� � � � x u l b w f | n d e f m g b q l b p x u f � a f b � d t ` j q l b d x g m � w f � ` � u g m g � l u g ` b ` s l j g l w f hg b l b l w | u g v l w v a f m g h u j | d � � � � � � � � � � � � � � � � � � i � � � � � � � � � y � � � � y i t l j v a � � � d

� � � � _ d c d e f b b g h i _ j d l b p � ` f j u { d x v a b l f w d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �

� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � d r j f b u g v f � o l w w i � b v d i c b q w f z ` ` p k w g ! h in f z _ f j h f | i � � � d

� � � � _ d c d e f b b g h i _ j d l b p e d _ d ~ ` ` p h d � � u g m g � l u g ` b ` b m g v j ` v ` m � � u f j h � � a fn f w p f j � t f l p h g m � w f � l w q ` j g u a m d � b y j u a � j ~ ` � � i f p g u ` j i � � � � � � � � � � � � � �

� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � i � l q f h � � � � � � � d x � y t ir a g w l p f w � a g l i � � � d

� � � � r a g w g � c d g w w i ~ l w u f j t � j j l | i l b p t l j q l j f u o d ~ j g q a u d � � � � � � � � � � � � � � � � � � � dy v l p f m g v r j f h h i � ` b p ` b i � � � d

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� � �

� � � � � ` f j u o ` ` � f l b p � d y d _ f f f h d � e g j f v u h f l j v a h ` w � u g ` b ` s b � m f j g v l w l b p h u l u g h �

u g v l w � j ` w f m h d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � i � � � � � � � � �

� � i y � j g w � � � d

� � � � x d � d x d _ l v ` | i _ d x d } ` z l w g � i l b p _ d � d r g � � ` d � � � � � � � � � � � � � � � � � � � � � � � � � � � �

� � � � � � � � � � � � � � � � � d r j f b u g v f � o l w w i � b v d i c b q w f z ` ` p k w g ! h i n f z _ f j h f | i � � � d

� � � � g v a l j p e d } j l � h f l b p _ ` a b y d � ` u u d � h f ` s u a f h g m � w f � m f u a ` p u ` ` � u g m g � fl b l w | u g v l w v ` b p g u g ` b h g b v w g b g v l w v a f m g h u j | d � � � � � � � � � � � � � � � � i � � � � � � � � � � � � � i� � � d

� � � � � l b q | f � g l b p � a ` m l h � d k ` w f m l b d y b f z m f u a ` p s ` j h ` w g b q u j g l b q � w l jh | h u f m h ` b l p g h u j g � u f p m f m ` j | m f h h l q f � � l h h g b q m � w u g � j ` v f h h ` j d � f v a b g v l w� f � ` j u k x � � � � � � � i k ` m � � u f j x v g f b v f e f � l j u m f b u i k ` j b f w w � b g f j h g u | i � � � d

� � � � � l b q | f � g l b p � a ` m l h � d k ` w f m l b d y � l j l w w f w u j g l b q � w l j h ` w f j s ` j l p g h �

u j g � u f p m f m ` j | m � w u g � j ` v f h h ` j d � � � � � � � � � � � � � � � � � � � �� � � � � � � � � � � � � � � �

� � � � � � � � i � � � � � � � � � � � i t l | � � � d

� � � � _ ` j q f _ d t ` j �f i { � j u ` b x d l j ` z i l b p } f b b f u a c d o g w w h u j ` m d � f h u g b q � b v ` b �

h u j l g b f p ` � u g m g � l u g ` b h ` s u z l j f d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � i� � � � � � � � � � i t l j v a � � � d

� � � � x u f � a f b � d t ` j q l b l b p x u l b w f | n d e f m g b q d x g m � w f � ` � u g m g � l u g ` b ` s l b l w | u g v l wv a f m g v l w m f u a ` p h d � � � � � � � � � � � � � � � � � � i � � � � � � � � � � � � � � i y � q � h u � � � d

� � � � _ d y d n f w p f j l b p � d t f l p d y h g m � w f � m f u a ` p s ` j s � b v u g ` b m g b g m g � l u g ` b d � � �

� � � � � � � � � � � � � � i � � � � � � � � � � � � i _ l b � l j | � � � d

� � � � _ d t d � j u f q l l b p ~ d k d � a f g b ` w p u d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �

� � � � � � � � � � � � � � � � � � d y v l p f m g v r j f h h i n f z � ` j � i � � � d

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� � �

� � � � _ d t d r l j � g b h ` b l b p e d o � u v a g b h ` b d y b g b f h u g q l u g ` b g b u ` u a f f � v g f b v | ` s l j g l b u h ` b u a f h g m � w f � m f u a ` p d � b � d y d � ` ` u h m l i f p g u ` j i � � � � � � � � � � � � � � �

� � � � � � � � � � � � � � � � � � � � � � � i � l q f h � � � � � � � d y v l p f m g v r j f h h i � ` b p ` b l b p n f z� ` j � i � � � d

� � � � t d _ d e d r ` z f w w d y b f � v g f b u m f u a ` p s ` j � b p g b q u a f m g b g m � m ` s l s � b v u g ` b ` s h f �

f j l w l j g l w f h z g u a ` � u v l w v � w l u g b q p f j g l u g f h d � � � � � � � � � � � � � � � � � i � � � � � � � � �

� � � i _ � w | � � � d

� � � � d � d � g u u f j i x d � d � ` z j | i k d � d ~ g w � g b h i l b p � d � d � h f b a ` � j d x g m � w f � � l u u f j bj f v ` q b g u g ` b d � � � � � � � � � � � � � � � � � � i � � � � � � � � � � � � � � i � v u ` f j � � � d

� � � o d o d � ` h f b j ` v � d y b l � u ` m l u g v m f u a ` p s ` j � b p g b q u a f q j f l u f h u ` j w f l h u l w � f` s l s � b v u g ` b d � � � � � � � � � � � � � � � � � i � � � � � � � � � � � � i � v u ` f j � � � d

� � � � t d ~ d � ` � u a i r d y d x z l j u � i l b p t d { d e f b u ` b d r f j s ` j m l b v f ` s u a f h � � f jm ` p g � f p h g m � w f � d � � � � � � � � � � � � � � � � � � i � � � � � � � � � � � � � i y � q � h u � � � d

� � � � � d { d x v a b l f w d k ` b v � j j f b u s � b v u g ` b f l w � l u g ` b h g b w ` v l w l b p q w ` l w ` � u g m g � l u g ` b d� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � i � � � � � � � � � � i � � � d

� � � � ~ d x � f b p w f | i d � d o f � u i l b p � d � d o g m h z ` j u a d x f � f b u g l w l � � w g v l u g ` b ` s h g m � w f �

p f h g q b h g b ` � u g m g h l u g ` b l b p f ` w � u g ` b l j | ` � f j l u g ` b d � � � � � � � � � � � � i � � � � � � � � �

� � � i n ` f m f j � � � d

� � � � ~ d o d x z l b b d e g j f v u h f l j v a m f u a ` p h d � b ~ d t � j j l | i f p g u ` j i � � � � � � � � � � � � � � �

� � � � � � � � � � � � � � � � � � � � � � � � � � i � l q f h � � � � � d y v l p f m g v r j f h h i � ` b p ` b l b p n f z� ` j � i � � � d

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� � �

� � � � e d y d ~ l w m h w f | d � a f h g m � w f � m f u a ` p s ` j m g b g m g h l u g ` b ` s l q f b f j l w s � b v u g ` b d x � � �

� w f m f b u l j | � f � ` j u � � � i y h h f h h m f b u e g g h g ` b i � j l b h � ` j u x | h u f m h e f � l j u m f b u i� j l b h � ` j u l b p � ` l p � f h f l j v a � l ` j l u ` j | i k j ` z u a ` j b f i { f j � h a g j f i � � � d

� � � � � � ~ f b � v g d � a f v ` b f j q f b v f � j ` � f j u | ` s u a f h g m � w f � f ` w � u g ` b l j | u f v a b g � f h d� � � � � � � � � � � � � � i x � f v g l w � h h � f ` s t l u a f m l u g v h � � � i � � d

� � � � � � ~ f b � v g d r ` h g u g f l h g h l b p l v w l h h ` s p g j f v u h f l j v a u f v a b g � f h d � � � � � � � � � � � � � � ix � f v g l w � h h � f ` s t l u a f m l u g v h � � � i � � d

� � � � } d y d ~ g w w g l m h ` b d � � � � � � � � � � � � � �� � � � � � � � � � � � � � � � � � � � � � � � � �� � � � � � � � �

� � � � � � � � � d r a e u a f h g h i � g v f � b g f j h g u | i o ` � h u ` b i � f � l h i � � d � b � j f � l j l u g ` b d

� � � � e l b g f w _ d ~ ` ` p h d � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �

� � � � � � � � � � � d r a e u a f h g h i � g v f � b g f j h g u | i � � � d

� � � ~ g w w l j p � d � l b q z g w w d t g b g m g � g b q l s � b v u g ` b z g u a ` � u v l w v � w l u g b q p f j g l u g f h d � � �

� � � � � � � � � � � � � � i � � � � � � � � � � � i n ` f m f j � � � d