33

£K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

Embed Size (px)

Citation preview

Page 1: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

������������ ������������������

� �"!�#%$&'$)(+*-,/.�(+$1032546.�(+(+$&7,/$146.8&7,/(+.89:9;*-,/.�2"&<46.�(+(=$)&7,/$>�?-@1ACB�?�DFEHG6?�I%IFJKJLIF?�DFEM@ONPIQ?�IFNHNH@SRT@OU6U6EHGOVXW�@YVLZ[IQ\�IFE�]FE^V[]FB�EPZKE�IFNHI_ZKZKV[G6?�EP]FE�`ITVa@YW�W�V[IbJKIF?cZa@YZa@\-@ONdU6IF?�IbVa@YZKGOV[Ie]FG6?cZKV[G6NPNM@YZ[G�f�>�?�U6IF?�I_Va@YZ[GOV[Ig]FG6?hZLV[G6NHNH@YZ[Gi`IgB�?�\�EHJ�W7G6JKE^Z[EPjcGk@l\�B�IeW8GOVKZ[IOmn B�EP?�\�E�]FG6? n B-@YZLZKV[GoZ[IbVKRTEH?-@ONPEpmq]ar�IQJKEsVKEH\�B�]FG6?�G1Z[BZKZ[@/j)EM@k?�IFNPNM@1Rt@OU6U6EPGOVuW�@YVKZKIt\�IFE�]v@OJKE@lZKVKIOmqW7I_V[]ar�wIt\�B�ItJKG6?�G1EH?x]FG6RyB�?�IeZLVa@kEH?�UOVKIFJKJKG1ITB�JL]FEPZa@fQz{V[IF?�\�EM@OReGoEH?�EPDFEM@ONPRTIF?cZ[IgEP?]FG6?�JKEP\�IbVa@ODFEPG6?�IoEHN5U6Ib?�IbVa@YZ[GOV[Il\�E�]bGOVKV[IF?cZ[Ik]bG6?hZKVKG6NHNM@YZKGiEP?|]FGOVKV[Ib?hZ[IYmsW7IbVK]}rswI n B�IFJLZKG~W-Bq`GIFJKJLIbV[I�@YW�W�V[G6JKJLEHRt@YZ[G�ZKVa@ORTE^Z[ISEHN�ZKVa@O?�JKEPJLZ[GOV[I~�-E^W7G6NH@YV[I�@|U6EPB�?�DFEHG6?�I��"��E^W7G6NH@YVo�6B�?�]bZ[EPG6?� Va@O?�JLEHJLZ[GOVFm5��� ��� fd��?�ACGOV[Rt@iEP\�Iv@ONHI%Za@ONHIlU6IF?�IbVa@YZKGOV[IkW-Bq`GxIFJKJLIbV[IoVa@YW�W�V[IbJKIF?cZa@YZ[Gx]FG6?�NPGJK]ar�IFRt@�]ar�I�JKIFU6B�IOf

�'@ n B-@O?hZ[E^ZY`@���]}r�I�Va@YW�W�V[IbJKIF?cZa@uEPNVa@YW�W7GOVKZKG�ZLVa@�NM@�]FGOVKV[IF?cZ[I�\�E�B�JK]FE^Za@�I n B�IFNHNH@�\�E�EH?�UOV[IFJLJKGjEPIF?�I�\�Ib�-?�E^Z[G|�LU6B-@O\-@OU6?�GQ\�E3]bGOVKV[IF?cZ[IF��f���GOZ[EH@ORTGe]ar�I�Np��EPReW7Ib\�IF?�Dv@T\�E3EP?�UOV[IFJKJKG�`I�JLZa@YZ[@JK]FIbNPZa@tjcG6NHBZa@OReIF?hZKI�?�B�NPNM@tEH?�RTG)\�Gt]ar�I�NM@t]FGOVKVKIF?hZKIg\�E�EP?�UOV[IFJKJKG%JKEH@%Rt@OJLJKEHRt@f���GOZKEM@ORTG@O?�]ar�I�]ar�I�EHN\�EPJLW7G6JLEPZ[E^jcG�`I�B�?�EP\�EPV[IFDbEHG6?-@ONHIYmh]bEHG�`I5]ar�I�NPI�UOVa@O?�\�IFDFDFI�IFNPIbZKZKV[EP]ar�I�I_jcIF?hZKB-@ONHRTIF?)�Z[IQ@YW�W-NPEH]v@YZ[IQ@ONPNp��B�JK]FEPZ[@o?�G6?�EP?�-B�IF?�Dv@O?�GiEH?�@ONH]FB�?�RTG�\�G n B�IFNPNHItEP?�EP?�UOV[IFJKJLG�f�z�G6JLJKEM@ORTGA;@O]FEPNHRTIF?cZ[I�]v@ONH]bG6NM@YV[I�EHN7Va@YW�W8GOVKZ[G�ZKVa@gNH@�Z[Ib?�JKEHG6?�Iu�6��I n B�IFNHNH@g�O �\�E¡B�JK]FE^Za@¢

£K¤�¥ �O�¦u§ �6  ¥©¨ � £K¤ ¦�ª ¥©¨ ��¦�ª¦u§ �O�+«

¬ I���¦�ª®­Y¦u§~`I�Rt@OU6U6EHGOV[I¯\�IFNHN"��B�?�EPZ=`@S° �6 h°h±²° �O�6°cI�JKE8r-@ n B�EH?�\�E®B�?%U6B-@O\-@OU6?�Gg\�E7Z[Ib?�JKEHG6?�IOf¬ I�EH?�G6NPZLV[Iy�³±µ´6m®]bG6RTIy\�E�JKG6NHE^Z[G%@O]F]v@O\�I�EH?iW�V[@YZ[EH]v@m®JLE{r-@%@O?�]ar�IgB�?®��@OReW-NHE^�-]v@ODFEPG6?�I�\�E]FGOVKVKIF?hZKIOf ¬ IgEPN3W�V[G)\�GOZLZ[GQ\�IFNdU6B-@O\-@OU6?�Gl\�E�Z[IF?�JLEHG6?�IyW7IbV n B�IFNPNHGQ\�Ed]FGOVKV[Ib?hZ[IYm'�   ¦�ª®­Y¦u§`IyRt@OU6U6EHGOVKIX\�IFNPNp��B�?�E^ZY`@tJKE�r-@tB�?iU6B-@O\-@OU6?�G%\�EqW8GOZ[IF?�Dv@¢�JLEHU6?�EP�-]F@ n B�EH?�\�E3]ar�Il`I�W7G6JKJKE^�-EHNPI]FG6?cZKV[G6NPNM@YV[Ig]FG6?xB�?�W-EH]F]bG6NHGoJKIbU6?-@ONHITB�?xJKIbU6?-@ONHIe\�E{W7GOZ[Ib?�Dv@kRt@OU6U6EPGOV[IOfTz{V[GOW�V[EHG n B�IFJ�Z[GIb¶8IbZKZ[G�Va@YW�W�V[IFJKIb?hZa@TNH@g]v@YV[@YZKZ[IbV[EPJLZ[EP]v@yW8IF]FB�NPEM@YV[Iu\�IFE¡]FG6JKEH\�\�I_ZKZ[E¯�L]FG6ReW7G6?�Ib?hZ[E¡@YZLZ[EPj)EH��m\�IFEn B-@ONPE¡EHN'��� � J[@YVY`@gEHN¡W�V[EHRTGgIFJKIFRgW-EHGT]ar�I�IFJK@ORTEH?�IbVKIFRTG�f `·<EHReW8GOVKZa@O?cZ[I�JKGOZKZ[G6NPEH?�Iv@YV[I��-?�G\-@1GOVa@o]ar�ItNM@kW8GOZ[IF?�Dv@1EH?xW-EK`B�]ar�ItJKE�W�V[IFJKIF?cZa@�@ONHN"��B�JK]FE^Za@lV[EPJLW7I_ZKZ[GS@ n B�IFNPNM@kEP?�EH?�UOV[IFJLJKGW�V[G/jEPIF?�Is\-@ONPNM@¯JKGOVKU6IF?hZKIs\�E�@ONHEHReIF?hZ[@ODFEHG6?�IOm=]ar�I�`IsJKIbReW�V[Is?�Ib]FIFJKJ[@YVKEM@¯W7I_V�EHNcACB�?�DFEPG6?-@ORTIF?cZ[G\�IFE¡\�EHJ�W7G6JKE^Z[EPj)E®@YZKZ[E^jEpf��{�¸@ORgW-NHEP�-]F@ODFEHG6?�I�\�E®W7GOZKIF?�Dv@l`I�\�E®ACG6?�\-@ORTIb?hZa@ONPIuEPReW7GOVLZa@O?�Dv@�?�G6?JKG6NPG¯?�IFNcZKVa@YZKZ[@ORTIF?cZ[G�\�IFE�JLIFU6?-@ONHEh@O?-@ONHG6U6EP]FEpm+Rt@�@O?�]ar�I�EH?u]v@OReW7G�\�EHU6E^Za@ONHIYm+W8IbV[]ar�wIOm6EH?�JLEHIFRTI]FG6?uNM@5W�V[GOW�V[EHI_ZY`@�\�E6B�?�EP\�EPV[IFDbEHG6?-@ONHE^ZY`@m+]FG6?�JKIF?cZ[IsNH@�VKIv@ONHEPDFDv@ODFEPG6?�I�\�E6EP?hZ[I_VKV[BZKZ[GOVKEh]bG6Rt@O?�\-@YZ[E]ar�I�]FG6?cZKV[G6NPNM@O?�G¯]bGOVKV[IF?cZ[EcW-E[`B�UOVa@O?�\�Eh\�E n B�IFNPNM@�\�Eh]FG6Rt@O?�\�G�I n B�EH?�\�Ec\�EhVKIbZ[Eh]}r�Is?�G6?�\-@O?�?�GNHB�G6U6Ge@g\�IFUOV[@O\�Ge\�IFE NHE^jcIFNHNPE®NHG6U6EH]bEpf

>�?-@Q\�IFJK]bVKEHDFEPG6?�IgRTG6N^Z[GtBZ[EPNHIy\�IFN�]FG6ReW8GOVKZa@ORTIb?hZ[Gt\�E�B�?�U6IF?�IbV[@YZ[GOV[I�]FG6Rt@O?�\-@YZ[GtJKEGOZKZ[EPIF?�I�ZKVa@OReEPZ[I�NH@�Va@YW�W�V[IFJKIb?hZa@ODbEHG6?�I¯UOV[@Y�-]v@�\�IFNHNPI�]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I�\�E)EH?�UOV[IFJLJKGuI�\�E�B�JK]bEPZa@mJKGOZKZKGlNH@QACGOVKRt@%\�E�A;@OReEHU6NHEPI�\�Ed]FBVKjcIOfX�'I�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�Iy\�EdEH?�UOV[IFJLJKG%jcIb?�U6G6?�GlZKVa@O]b]FEM@YZ[IJKB�NqW-EH@O?�GQ� ¤ � £L¤ I�Va@YW�W�V[IFJKIb?hZa@O?�GlEHN NHIFUc@OReIXZKVa@eZa@ONPEqUOVa@O?�\�IbDFDFIyEH?1ACB�?�DFEPG6?�Iy\�E3B�?-@t\�IFNHNPIUOVa@O?�\�IFDbDFIl\�EsB�JK]FEPZ[@fi��IFNs]v@OJKGSW�@YVKZ[EH]bG6NM@YV[RTIb?hZ[IeJKIFReW-NPEH]FIQ]FG6?�JKEP\�IbVa@YZ[G�?�G6?�r-@�JLEHU6?�EP��]v@YZ[GtZKV[@O]F]FEM@YVKI�NHIy]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I�\�E�EH?�UOVKIFJKJKG�m®\-@YZ[GQ]ar�I�� ¤ `IyJKIFReW�V[I�?hB�NHNH@fuz�I_V n B-@O?hZKG

¹ ´

Page 2: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

V[EPU6B-@YV[\-@kEH?cjcIF]FItNPIe]v@YV[@YZKZ[IbV[EPJLZ[EP]}r�Ie\�EsB�JK]FE^Za@m n B�IFJLZ[IejcIb?�U6G6?�GkVa@YW�W�V[IFJLIF?hZ[@YZ[IQJKB�N{W-EH@O?�G�6 }� £  Ym7EP?�ACB�?�DbEHG6?�Iy\�IFNHNH@ £K¤ �:W7I_V�B�?i?hB�RTIbV[Gt\�EPJK]bV[I_Z[GQ\�EqjO@ONPGOV[Eq\�IbNHNM@ £L¤}� f�z�IbV�EHN'U6IF?�IbVa@=�Z[GOV[I�\�E ]FGOVKV[IF?cZ[I�EP\�Iv@ONHI�]FG6?cZKV[G6NPNM@YZ[GgEH?k]bGOVKV[IF?cZ[IOm�NHI�]v@YVa@YZKZ[I_V[EHJLZKEH]ar�IX\�E B�JK]FE^Za@gJKG6?�GeRTG6NPZ[GJKIFRgW-NHEH]bEp¢XEP?�]FGOVKVKEHJLW8G6?�\�IF?�Dv@o\�E{G6U6?�E{jY@ONHGOV[I�\�IFNPNM@ £K¤ JKE�r-@lB�?-@lV[IbZKZ[@lW�@YVa@ONHNPIFNM@l@ONHN"�¸@OJKJKI\�IFNPNHI�@OJK]bEHJKJKI�I�\-@TIbJKJKGQ\�EHJLZ[@O?hZ[IX� £K¤ m�j)EHJLZ[Gt]ar�I�NH@T]FGOVKV[IF?cZ[I�\�E'B�JK]FEPZ[@1`IXW�V[GOW7GOVKDFEHG6?-@ONPIy@£K¤ IXEH?�\�E^W7IF?�\�Ib?hZ[IX\-@ON¡jY@ONHGOVKIu\�E¡�6 Yf

¬ IXW�V[Ib?�\�EM@ORTGtEP?o]FG6?�JKEP\�IbVa@ODFEPG6?�I�B�?�]bEPV[]FB�E^Z[GT]FG6ReI n B�IbNHNHGe\�EqJKIFU6B�E^Z[GTVa@YW�W�V[IbJKIF?cZa@YZ[G�m8EP?]FB�E�JLB�NHNp��B�JK]FE^Za@�`Io]FG6NHNPIFUc@YZ[GxB�?�U6IF?�IbV[@YZ[GOV[I1\�E¯Z[Ib?�JKEHG6?�I�º�»®»�ZLVa@ORTEPZKIkB�?�V[IFJKEPJLZ[GOV[I1¦u YmW7G6JLJKEM@ORTGuEH?�\�EP]v@YV[I¯NH@�V[IbNM@ODFEPG6?�I�ZKVa@u�6 �I £  �EHRgW7G6JLZa@�\-@ONHNH@�V[I_Z[I�IFJLZKIbV[?-@uW8IbV�RTIbDFDFG�\�E�B�?-@V[IbZLZa@t\�E3]v@YV[EP]FG�m®]ar�IyW-Bq`G%IFJKJLIbV[IyV[EPW8GOVKZa@YZa@TJKB�N'W-EM@O?�G%\�IFNHNPI�]v@YVa@YZKZ[I_V[EHJLZKEH]ar�IOf��q@tW�V[IFJLIF?�Dv@\�IFN�U6IF?�IbVa@YZ[GOVKI�º�»®»~W-Bq`G�JKIbRy��V[@YV[I�@ n B�IbJLZ[G�JLZa@O\�EPG�@YVKZ[E^�-]FEHG6JK@m)\-@YZ[G�]ar�I�]FG6RgW7GOVKZa@uJKIFRg�W-NHEP]FIFRTIb?hZ[I�N"�¸@OU6U6EPB�?hZa@g\�E3B�?�jY@ONHGOV�RTIF\�EHGT@ONHNM@eZKIF?�JKEHG6?�I�\�EqB�JK]FEPZ[@f�¼sIF\VKIFRTGeW-EK`B~@vjO@O?cZ[E]FG6RTIYm�?�IFN�]v@OJLG~\�E�B�?|\�EHJ�W7G6JKE^Z[EPjcGSV[Iv@ONPIOm n B�IFJLZa@SJKEM@�EH?cjcIF]FIlEH?�\�EHJ�W7IF?�J[@Y�-EPNHI%W7IbVgACGOV[?�EPVKINp��IF?�IbV[U6EH@g?�IF]bIFJKJ[@YV[EH@T@ON¡JKB�GeACB�?�DbEHG6?-@ORTIF?cZ[G�f

½ IbV[]ar�EM@ORTGgGOVa@e\�E \�IbZ[IbVKRTEH?-@YV[IuNp��@O?�\-@ORTIF?cZ[Ge\�IFNPNM@gZKIF?�JKEHG6?�IX\�E'B�JK]bEPZa@eEP?oACB�?�DFEPG6?�I�\�IFNHNH@]FGOVKVKIF?hZKI £K¤ f¿¾�N�jO@YVKEM@YV[Il\�E £K¤ EPN�W-B�?cZ[G�\�E¯NM@vjcGOV[G�JLE¯JLW8G6JLZa@�NHB�?�U6GxNH@iV[IbZLZa@�\�E¯]v@YVKEH]FG�¢Va@YW�W�V[IbJKIF?cZ[EM@ORTG�NM@x]FGOVLV[IF?cZ[I £L¤ EP?¿ACB�?�DFEPG6?�I~\�IFN�ZKIFReW7G�@�NM@YZ[G�\�IFNPNM@x]v@YVa@YZLZ[IbV[EPJLZ[EH]F@�\�EB�JK]FE^Za@�IOm�W8IbV�G6U6?�E�jY@ONHGOVKI�\�E £K¤ m)@O?�\�EM@ORTGy@�EP?�\�EPjEP\�B-@YV[I�NH@�]FGOVKV[EPJLW7G6?�\�IF?cZ[I�]v@YVa@YZLZ[IbV[EPJLZ[EH]F@À/ [Áº� gI�NM@%VKIFNM@YZ[E^jO@%EH?cZ[IbV[JLIFDFEHG6?�Ig]FG6?�NH@%V[IbZLZa@l\�E{]v@YV[EP]FG�f���? n B�IFJLZ[GlRTG)\�G%GOZKZ[Ib?�EM@ORTG%EHNjY@ONHGOV[I�@ONPNp��EHJLZa@O?cZ[Iu]FGOVKV[EPJLW7G6?�\�IF?cZ[Iy\�IFNPNM@T�6 XI�NPGeW7G6JLJKEM@ORTGgV[EPW8GOVKZa@YV[I�EP?1B�?SUOVa@Y�-]FGtW7G6JLZKGJKGOZKZKG�@ONHNHI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I�\�EB�JL]FEPZa@fq��GOZ[EM@ORTG�]ar�I5NM@¯ACGOV[RT@�\®��G6?�\-@�\®��B�JL]FEPZa@�`I�B�?-@¯VKIbW-NHEP]v@@OReW-NPEP�-]v@YZa@m)EH?cjcIbVKZ[E^Za@g\�E¡A;@OJKIuIuZKVa@OJLNM@YZa@y\�E n B�IFNPNM@g\�E¡EP?�UOV[IFJKJKG�f

� �;ÂiÃF9�Äq(Y2:&34c2:Ä32:.x0q2�ÅÇÆ3&qÈh2:.�&q*�É�$&7,/.~0q$9sÊ�Ë¡Ì��NqZKVa@O?�JLEHJLZ[GOVKI��-EPW7G6NH@YV[I�@tU6EHB�?�DbEHG6?�Iy]FG6?�JKEPJLZ[I�\�E3\�B�IyU6EHB�?�DbEHG6?�E�Í�ÎxW7G6J�Z[I�B�?-@t\�E3JKIFU6B�E^Z[G@ONHN"�¸@ON^ZKVa@eI�GOVKEHIF?cZa@YZ[I�EP?�JLIF?�JKGQEH?cjcIbV[JKG�¢�JKE'ZLVa@YZKZa@ n B�EH?�\�Eq\�E'ZKV[I�V[IFU6EPG6?�Eq]FG6?�JLIF]FBZ[E^jcIOm®B�?-@Í m7B�?-@TÎxI�B�?-@uÍi?�IFN']v@OJKGQ\�EqB�?S\�EHJ�W7G6JKE^Z[EPjcGuÍ�Î)ÍiI�B�?-@tÎ�m�B�?-@�Í�IXB�?-@QÎx?�IbN3]v@OJKGt\�IFE\�EHJ�W7G6JKE^Z[EPj)E�Î)Í�Î�fi�'@1]v@YVa@YZKZKIbV[EHJ�Z[EH]v@1ACG6?�\-@ORTIb?hZa@ONPIQ]}r�I%\�EHJ�Z[EH?�U6B�IQEHN�ZKVa@O?�JKEPJLZ[GOV[IQ\-@1\�B�IU6EHB�?�DbEHG6?�EsÍ�ÎÏEH?<JKIbV[EPIÐ����@O][Ñh�ÒZ[GY�p��@O]aÑ)�¿`I1Va@YW�W�VKIFJKIF?cZa@YZa@�\-@ONHNHG�JLW8IFJKJKGOV[I�IFJLZLV[IFRt@ORTIb?hZ[IV[EP\�GOZKZ[G�\�IFNHNH@�DFG6?-@�]FIF?cZKVa@ONPI|�:?�G6?¿Va@YW�W�V[IbJKIF?cZa@YZ[GÓ]bGOVKV[IbZKZ[@ORTIF?cZ[ISEH?<JK]v@ONM@�?�IFN�\�EHJLIFU6?�G

¹cÔ

Page 3: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

JKGOZKZKG6JLZa@O?cZ[I � m�]ar�IOm{]FG6RTIejcIb\V[IFRTG�m�\q`@1NHB�G6U6G�@ONPNp��EP?hZKIbVa@ODFEPG6?�IeZKVa@oNPIt\�B�I%U6EPB�?�DFEHG6?�E"md@ONHNH@��@OJKIu\�IFNHN"�Õ�LIb¶8IbZKZ[G�ZKVa@O?�JKEPJLZ[GOV[��f�{��IFNPIbZKZKV[G�\�G�]FIF?cZKVa@ONPI�jEHIb?�I�\�Ib�-?�EPZ[G���@OJKIYm�RTIF?cZKV[I�U6NPE7@ONPZLV[E�\�B�I�JKG6?�Gy\�IF?�G6ReEH?-@YZ[E�IFRTIbZLZ[E^�Z[GOV[I�I�]FG6NPNHIbZKZKGOV[IOfq��N�\V[G6Uc@OU6U6EPG�\�IFNHNPI�\�B�I�V[IFU6EPG6?�EIFJLZ[I_V[?�I�?�G6?k`I�B�U6B-@ONHIO¢3EP?gB�?yZKVa@O?�JLEHJLZ[GOVKINM@uDFG6?-@�\�E8IFReIbZKZ[E^Z[GOV[IX`I¯JKEHU6?�E^�-]v@ORTIF?cZ[I¯W-EK`Bt\V[G6Uc@YZa@X\�E n B�IFNPNHI�\�E���@OJKI�I�\�E�IFRTIbZKZKEPZ[GOV[IYÖ�JKEEH?�\�EP]v@XEP?�A;@YZKZ[E�]FG6?uÍ8×~?�IbE�ZKV[@O?�JKEHJLZKGOV[EOÍ�Î)ÍtI¯]bG6?TÎ ×i?�IFE-ZKVa@O?�JKEPJLZ[GOV[E-Î)Í�Î�f���IFNPNM@�ZKVa@YZKZa@ODbEHGY�?�I�\�IFN-RTG)\�IFNPNHG��-JKEP]FGX\�IFN�ZKV[@O?�JKEHJLZKGOV[I5Z[BZKZ[I�NHI�]FGOVKVKIF?hZKE-jcIb?�U6G6?�GX\�E-JKG6NHE^Z[G�JK]FIFN^Z[I�]FG6?gjcIbVKJKGIF?cZKVa@O?cZ[IOf���ZLVa@O?�JKEHJ�Z[GOV[E'jcIb?�U6G6?�GlEP?�\�EH]v@YZ[E'?�IFU6NHEqJK]ar�IFRTE�]FE^V[]FB�EPZ[@ONHEq]bG6?�EqJKEHR��7G6NPEqJKGOZLZ[G6EH?)�\�EH]F@YZ[Epm�]ar�I�\�E^¶7IbV[EPJK]FG6?�G�m�ZKVa@�Í�Î)Í1IuÎ)Í�Î�m�JKG6NHG�W7IbV¯EHN7jcIbV[JLGT\�IFNHNH@gAMV[Ib]F]FEM@g\�IFNHN"��IFRTI_ZKZ[EPZKGOV[IOf

Ø�@ONhW-B�?cZ[G�\�EhjEHJ�Za@�]FG6J�ZKV[BZKZ[E^jcG�E���� � ?�G6?�jcIF?�U6G6?�G¯VKIv@ONHEPDFDv@YZ[Eh]FG6?�?�IbZKZKIF?�\�G�EH?�JKEPIFRTI�W8IFDFDFEJKIbW�@YV[@YZ[E�\�E�JKEHNPEH]FEPG�]FG6?�\�E^jcIbV[JKG�\VKG6Uc@OU6U6EHG�mO@O?�]ar�I�W8IbV[]ar�wI5EH?�Za@ONcRTG�\�G�J[@YV[I_���7Is�8IF?�\�EPÙe]FEHNPIV[EPB�JK]FEPVKIg@tGOZKZKIF?�IbV[I�U6NHE'JLW7IFJLJKGOV[Ed\�Eq��@OJKIyIFJLZLV[IFRt@ORTIb?hZ[I�VKEH\�GOZKZ[Eq]}r�I�JKG6?�GtV[EP]}r�EPIFJLZ[E3W8IbV�EHN]FGOVKVKIbZKZ[GoACB�?�DbEHG6?-@ORTIF?cZ[G�ft>�?�W�V[G�]FIFJKJLGoZ[IF]F?�G6NPG6U6EH]FGoJ�Za@O?�\-@YV[\~W8IbV�NM@lA;@Y����V[EH]v@ODbEHG6?�IT\�IFEZKVa@O?�JLEHJLZ[GOVKE8`I n B�IFNHNPG�W-NM@O?-@YV[IOmYEHNHNPB�JLZKVa@YZKG�\�EJKIFU6B�E^Z[G�Is��@OJ[@YZKG�JKB�NHNH@�JKB�]F]FIFJLJKEPjY@�VKIv@ONHEPDFDv@ODFEPG6?�I\�E¯J�ZKVa@YZ[E�]FG6?�\�EPjcIbVKJKGx\V[G6Uc@OU6U6EHG�f<�{��IFJKIbReW-EHG�W�V[IbJKGxEH?�]FG6?�JLEH\�IbVa@ODbEHG6?�I�`I n B�IbNHNHGx\�E�B�?ZKVa@O?�JLEHJLZ[GOVKIuÎ)Í�Î�f

¹6¹

Page 4: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

¬ E'W�@YVLZ[IX\-@TB�?1JKB�-J�ZKVa@YZ[Gt\�E'JKEHNPEH]FEPGeRTG6?�G�]bV[EHJ�Za@ONHNPEH?�Ge\�E¡Z[E^W7GuÍ�JKB�N n B-@ONPIXjEPIF?�IXGOZLZ[IF?hBZ[GB�?�GoJLZLVa@YZ[GkÎÓ]}r�IgVa@YW�W�V[IFJKIb?hZa@oEPNd]FG6NHNPIbZKZ[GOV[IYf ¬ EdV[Iv@ONHEPDFDv@QW7G6E{B�?�GoJLZKVa@YZKGkIFJLZLV[IFRt@ORTIb?hZ[IJKGOZKZKEHNHIg\�E{ZKEPW7GyÍ m3]ar�It]FG6JLZ[E^Z[B�EHJL]FIeNH@l��@OJKITITEP?�-?�IejEPIF?�IeGOZLZ[IF?hBZa@oB�?-@kV[IFU6EPG6?�IeÎ ×Ð]ar�IVa@YW�W�V[IbJKIF?cZa@�Np��IFRTIbZKZKEPZ[GOV[IYfq�'@YZ[IbVa@ONPRTIF?cZ[I�jcIb?�U6G6?�GuV[Iv@ONPEHDFDF@YZ[I�\�IbNHNHI�V[IFU6EPG6?�EOÍ8×i]ar�I�r-@O?�?�GACB�?�DFEPG6?�Ik\�E�EHJKG6NH@ORTIF?cZ[G�\-@OE�ZKVa@O?�JKEPJLZ[GOV[E�@O\�EH@O]FIF?cZ[Epf��'@i\�Ib�-?�EPDFEHG6?�IlNM@YZ[IbV[@ONHI%\�IFNHNPI%jY@YV[EHIV[IFU6EPG6?�E�jEHIb?�I~GOZKZ[Ib?�BZa@�ZKVa@ORTE^Z[I1Z[IF]F?�EP]ar�I~NHE^Z[G6UOVa@Y�-]ar�IOf ½ G6?¿GOW�W7GOVKZ[B�?�IiW�V[G)]FIb\�BV[I~JKEGOZKZ[Ib?�U6G6?�Ge@O?�]ar�IX\�IbE ]bG6?hZa@YZLZ[E®IFNHI_ZKZKV[EP]FE®]ar�I�Va@OU6U6EPB�?�U6G6?�GeNPI�ZLV[I�VKIFU6EHG6?�E®\�IFN®ZKV[@O?�JKEHJLZKGOV[I�IVa@YW�W�V[IbJKIF?cZa@O?�GtNM@�]FG6?�?�IFJKJKEPG6?�I�]FG6?lEHN®V[IFJLZKGe\�IFN ]FEPVK]FB�EPZ[G�f

zd@OJKJLEM@ORTGtGOVa@t@tEP?hZKV[@YW�V[IF?�\�IbV[I�B�?�GQJLZ[B�\�EPGQW-EK`BS\�IbZKZa@OU6NPEM@YZ[Gt\�IFNqACB�?�DFEHG6?-@ORTIb?hZ[GQ\�IFN��� � f���IFNPNM@y?�G6JLZKVa@yZKVa@YZKZ[@ODFEHG6?�I�JKBW�W7GOVLV[IFRTGg]}r�IYm�IF]b]FIbZKZ[Gg]ar�IX?�IFNPNHI�DFG6?�IX\�E¡JLj)B�GOZa@ORTIF?)�Z[G�m'NM@k]FG6?�]bIF?hZLVa@ODFEHG6?�It\�EdW7GOVLZa@YZ[GOV[Ed?�IFNPNHIgZLV[IeV[IFU6EPG6?�EdJKEM@oJKBÙe]FEHIb?hZ[IgW7IbV�W8GOZ[IbVX]FG6?�JKEH\�I}�Va@YV[Ie?�B�NPNM@kNH@o]v@O\�BZa@o\�EdZ[IF?�JKEPG6?�IQ@YZKZKVa@vjcIbV[JKGk]FEM@OJK]bB�?-@o\�IFNHNPIeV[IFU6EPG6?�E�JLZKIFJKJKIO¢yNPIT]FGOVKV[Ib?hZ[E]ar�I�@YZKZKVa@vjcIbV[J[@O?�G�EPN¯ZKVa@O?�JKEPJLZ[GOV[I1JLG6?�G�\�B�? n B�I�ZKBZKZ[I1]FGOVKVKIF?hZKE�\�E�\�EP¶8B�JKEHG6?�IOf ½ G6?�JKEH\�I}�V[EH@ORTGkNH@kRTG)\-@ONPEPZY`@Q\�EsACB�?�DbEHG6?-@ORTIF?cZ[GoW-EK`B�Z[EPW-EP]v@mq]FEPG-`I n B�IFNHNH@k?�IFNHNH@ n B-@ONPIeNM@lU6EHB�?�DFEPG6?�I��@OJKI_�ÒIFRTIbZLZ[EPZ[GOVKIujEPIF?�IuW8G6NM@YV[EPDFDv@YZa@g\�EPV[IbZLZa@ORTIF?cZ[IOm-RTIF?cZKV[I n B�IFNPNM@���@OJLI_�Õ]FG6NPNHIbZLZ[GOV[IXV[EPJKB�NPZ[@W7G6NH@YV[EHDbDv@YZa@~EP?hjcIbVKJ[@ORTIF?cZ[IOf<��?�]bG6?�JKIFU6B�IF?�Dv@�\�IFNPNM@~W7G6NH@YV[EHDbDv@ODFEHG6?�Ik\�EPV[IbZLZa@iZKVa@~��@OJLI1IF\IFRTI_ZKZ[EPZKGOV[IOm8B�?-@t]FGOVLV[IF?cZ[I�\�E3NM@O]bB�?�Iyj)EHIF?�IXEH?�EHI_ZKZa@YZa@T\-@ONPNp��IbRTIbZKZ[E^Z[GOV[I�?�IFNHNH@T��@OJKIOm7RTIb?hZKVKIB�?-@T]FGOVKVKIF?hZKI�\�E'IbNHIbZKZLV[G6?�E®W�@OJKJ[@T\-@ONHNH@���@OJKI�@ONHNp��IFRTIbZLZ[EPZ[GOVKIOf�Ø�@YZ[Ge]}r�IYm8]FG6RTI�U6E�`@�JKGOZKZ[G6NPE^�?�Iv@YZ[G�m8Np��IbRTIbZKZ[E^Z[GOV[Ie`I�RTG6NPZKGeW-EK`BS\V[G6Uc@YZ[Gt\�IbNHNM@e��@OJLIOm®NM@T]FGOVLV[IF?cZ[I�\�E3NM@O]bB�?�I�EH?�EHI_ZKZa@YZa@eEP?��@OJKIuJ[@YVY`@gReG6NPZ[G�W-EK`BlUOVa@O?�\�IX\�E n B�IFNHNH@�\�E¡IFNPIbZKZKV[G6?�E¡EP?�EHIbZKZ[@YZa@�\-@ONHNM@y��@OJKI�?�IFNHN"��IFRTI_ZKZ[EPZKGOV[IOm]ar�I%W-Bq`GiIFJKJKI_V[I%ZLVa@OJK]FBVa@YZ[@f ¬ IlNH@oV[IFU6EHG6?�I%\�E���@OJKI%ACG6JKJKI%NHB�?�Uc@m{NM@1]FGOVKVKIF?hZKIk\�E5NM@O]bB�?�IEH?�EPIbZKZa@YZ[@S\-@ONPNp��IFRTIbZKZKEPZ[GOV[IYm3\-@YV[Ib���8IkNHB�G6U6G�@SB�?-@�]bG6?�]FIF?cZKVa@ODFEPG6?�IkEH?�IF]F]bIFJKJKGi\�E5NM@O]FB�?�IOm]ar�It\�IF]v@O\�IbVKIb���7I%IFJLW8G6?�IF?�DFEM@ONPRTIF?cZ[IT]FG6?�NH@o\�EHJLZa@O?�DF@o\-@ONHNM@lDFG6?-@1\�EsJLj)B�GOZa@ORTIF?cZ[G�fQ·sJ��JKIF?�\�GuW7IbVY`GuNM@���@OJKI�]FGOVKZa@�V[EHJLW8IbZKZ[Gu@ONHNH@�NPB�?�U6r�IFDFDv@u\�E�\�E^¶7B�JKEPG6?�I�W8IbV�NHI�NM@O]FB�?�IOmhJKG6NPGuW7G�]ar�INM@O]bB�?�I�V[EHIFJL]FG6?�G�@�VKEH]FG6R��-EH?-@YVKJKEpm�RTIF?cZKV[I�NH@�Rt@OU6U6EHGOV�W�@YVKZ[I�Va@OU6U6EPB�?�U6I�NM@�DFG6?-@�\�E7J�jB�GOZa@=�RTIF?cZ[GTZKV[@e��@OJKI�I�]FG6NPNHIbZKZKGOV[IOm8\�G/jcI�NHIXNM@O]FB�?�I�jcIF?�U6G6?�GtZKV[@OJK]FEH?-@YZKIXjcIbV[JKGtEPNq]FG6NPNHIbZLZ[GOV[I�\-@ON]v@OReW8GTIFNPIbZKZKV[EP]FGTA;@vjcGOV[IbjcG6NPIOf�>�?-@TUOV[G6JKJ[@eW�@YVKZKI�\�IFNHNH@e]FGOVKVKIF?hZKI�\�EqNM@O]bB�?�I�EH?�EPIbZKZa@YZa@g?�IFNHNH@��@OJKIg\-@ONHNp��IFRTIbZLZ[EPZ[GOVKI�Va@OU6U6EHB�?�U6I n B�EH?�\�EdEPN{]bG6NHNHI_ZKZ[GOV[IOm¡RTIb?hZKVKIeJKG6NPGkB�?-@%W-EP]F]FG6NH@kAMVa@ODFEPG6?�I\q`@gNPB�G6U6GT@yV[EH]FG6R��-EP?-@ODFEHG6?�I�EH?%��@OJKIOf

Ú

Û

Ü

Ý ÝÜ

Þ Û

ß:àÕá;á�â"ã[ä}å�æKß;ç_èbéä�è_äêéÕëPëPæKë^é

ß;àÕá:á�â"ã[ä}á;ä�ß;àÕì'íKäêèbæLîÒäêàÕèbé

ß:àÕá;á;éÕèbë^é�äêèbï�éÕá;ð"æ8ñ�ëPá;æKð"ß;çbá;æKíKäêå�é}òß;àÕá:á;éÕèbë^é�ã[ä}éÕåêéÕëPëPéÕëPë^á:àÕè_ää�è_äêéÕëPëPæKë^æ8ñ�ëPá:æLð"ß:ç_á;æKíKäêå�é}ò

ó ô

õ

�'@�]bGOVKV[IF?cZ[IS\�E¯��@OJKI�`I n B�EP?�\�E�JKG6JLZ[@O?�DFEM@ONPRTIF?cZ[Io]FG6JLZKEPZ[B�E^Za@�\-@ON¯�-B�JKJKG�\�E�IFNPIbZKZKVKG6?�E¯]ar�I

¹Oö

Page 5: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

\-@O?�?�G�NHB�G6U6G�@ONHNH@�VKEH]FG6R��-EH?-@ODbEHG6?�I�\�IFNPNHI�NM@O]FB�?�IYf�·�JKJKIF?�\�GgNM@�AMVa@ODFEPG6?�I�\�E®NH@O]FB�?�I�EH?�EPIbZKZa@YZ[I\-@ONHN"��IFReIbZKZ[E^Z[GOV[IT]ar�IQJKE�V[EP]FG6R��-EH?-@1EH?���@OJKI%RTG6NPZ[GlW-EH]F]FG6NH@m�NH@1]FGOVKV[IF?cZ[I%\�E���@OJKIi`ItRTG6NPZ[GW-EK`BiW-EH]F]FG6NH@l\�E n B�IbNHNHI�\�E{IFRTIbZKZKEPZ[GOV[I�Ig\�Ed]FG6NHNPIbZKZ[GOV[IYfg>�?-@QjO@YV[EH@ODFEHG6?�IyW7I_V[]FIF?cZ[B-@ONHIe\�IFNHNH@]FGOVKVKIF?hZKIX\�E®��@OJKIXJLE¡VKEPW7I_V[]FB�GOZ[Iu\�B�? n B�IXEP?kRTG�\�G�W�VKGOW7GOV[DFEPG6?-@ONHIuJKB�NHNH@�]FGOVLV[IF?cZ[I�\�E¡]FG6NHNPIbZL�Z[GOV[IYm \-@O?�\�G%NHB�G6U6Gl@QB�?~]FG6ReW8GOVKZa@ORTIb?hZ[Gt]bGOVKV[EHJ�W7G6?�\�IF?cZ[IT@ n B�IFNHNPGl\�E�B�?iU6IF?�IbVa@YZ[GOVKI�\�E]FGOVKVKIF?hZKIX]FG6?cZKV[G6NPNM@YZ[G�EH?o]bGOVKV[IF?cZ[IOf

� I�]FGOVKVKIF?hZKE3@ONHN"��EP?hZ[I_V[?�GT\�E B�?oZKVa@O?�JKEPJLZ[GOV[I�Í�Î)ÍoW7G6JKJKG6?�Gt\�B�? n B�I�IFJKJKI_V[I�IFNHIb?�]v@YZ[I�?�IFNRTG�\�GgJKIbU6B�IF?hZKIO¢�t]FGOVLV[IF?cZ[IX\�E NM@O]FB�?�IuEH?�EPIbZKZa@YZa@y\-@ONHN"��IFReIbZKZ[E^Z[GOV[I�?�IFNPNM@���@OJLI�t]FGOVLV[IF?cZ[IX\�E IFNHI_ZKZKV[G6?�E®EP?�EHIbZKZ[@YZa@g\-@ONPNM@���@OJKIX?�IFNPNp��IFRTIbZKZKEPZ[GOV[I��;ZKVa@OJK]FBV[@Y�-EHNHI ��t]FGOVLV[IF?cZ[I�\�E¡IFNHI_ZKZKV[G6?�E¡EH?l��@OJKIOm�]FGOVKV[EPJLW7G6?�\�IF?cZ[I�@ONPNM@�V[EH]bG6Ry�-EP?-@ODFEHG6?�I�\�E B�?-@eAMVa@ODFEPG6?�I\�IFNPNHIuNM@O]FB�?�IOf

�t]FGOVLV[IF?cZ[IXEP?hjcIbVKJ[@T@YZKZKV[@/jcIbVKJKGeNH@gU6EHB�?�DbEHG6?�I���@OJKI_�Õ]bG6NHNHI_ZKZ[GOV[IT�:ZKVa@OJK]bBVa@Y�-EHNPI ��t]FGOVLV[IF?cZ[IT\�E{NM@O]FB�?�IgEH?cjEM@YZ[@l?�IFNd]FG6NPNHIbZKZKGOV[IOm ]FGOVKV[EPJLW7G6?�\�IF?cZ[IQ@ONPNM@QAMVa@ODFEHG6?�Ie\�IFNHNH@l]FGOVL�V[Ib?hZ[I�W�V[G/jcIF?�EHIF?cZ[I�\-@ONPNp��IFRTIbZKZKEPZ[GOV[I�]ar�Iu?�G6?oJKE®V[EH]bG6Ry�-EP?-@gEP?l��@OJKIOf

� �M÷xøs$1$)ù®Æq*-È�2;.�&32�032�ú�û{$)(=ü_ýaþ©.�9:9`·ÿW7G6JLJKEP�-EPNHI�\�Ib�-?�EPV[IeB�?~RTG�\�IFNHNPGlRt@YZKIFRt@YZ[EP]FGt]ar�Ie\�IFJK]_V[EPjcIgEHNd]FG6ReW8GOVKZa@ORTIF?cZ[GtW7I_V

UOVa@O?�\�E®JKIbU6?-@ONHE®\�IFN7ZKV[@O?�JKEHJLZKGOV[I���� � mEH?�]bNHB�\�IF?�\�G�Z[BZKZ[I�NHI�]FG6RgW7G6?�IF?cZ[E7\�E®]FGOVLV[IF?cZ[IuJLGOW�Va@RTIF?�DbEHG6?-@YZ[IOf � @ONHI�RTG�\�IFNHNPG�m8\�Ib�-?�E^Z[GQRTG)\�IbNHNHGt\�Eq·��7I_V[J����SG6NPN3\-@OE3?�G6RTE \�E3]FG6NPGOV[GQ]}r�IyNPGW�V[GOW8G6JKIbV[G�m¡`I�?�IF]FIFJLJ[@YV[EM@OReIF?hZKIu?�G6?%NHEP?�Iv@YV[I�I�V[@YW�W�V[IFJKIF?cZa@�EHN7ZKVa@O?�JLEHJLZ[GOVKI�]bG6RTI�]FG6JLZ[E^Z[B�EPZKG\-@T\�B�I�U6EHB�?�DbEHG6?�E�Í�Îx]bG6?hZKV[@YW�W7G6JLZ[IX]FG6?SNp�¸@OU6U6EPB�?hZ[@g\�EqU6Ib?�IbVa@YZ[GOV[E'\�Eq]FGOVLV[IF?cZ[I�]FG6Rt@O?�\-@=�Z[E"m�]ar�Ik\�IbJK]bV[E^jcG6?�G~NM@1W7GOVKDFEHG6?�I%\�IFNHNH@i]FGOVLV[IF?cZ[Ik\�E5IFReIbZKZ[E^Z[GOV[ITZKVa@OJLACIbV[EPZ[@~@ON5]FG6NPNHIbZKZKGOV[IQIjEP]FIbjcIbVKJ[@f

Ø�@ONHNPG�JK]ar�IFRt@yJKGOW�Va@�Va@YW�W�V[IFJLIF?hZ[@YZ[G�mjO@ONPEH\�G�W7I_V�B�?%ZKV[@O?�JKEHJLZKGOV[IsÍ�Î)Í mGOZKZ[Ib?�EM@ORTG�NPI�]FG6JKEH\)�\�IbZKZKIXI n B-@ODFEHG6?�E¡\�E¡·��8IbV[J�����G6NPNp¢���� ��� À�� ¥ À�� ¨ ��� À��� ¥ À�q§������������� ¨ ´�� ¨�� � À��'§!�"�#�%$&���� ¨ ´��

À�� ¥ À�� ¨���' À�� ¥©¨(� ' À��'§��"�����&��)� ¨ ´��+*�À��'§!�,�#�%$&���� ¨ ´��.-\�G/jcI � ' Va@YW�W�V[IFJKIb?hZa@�NM@�AMVa@ODFEHG6?�I{\�IFNPNM@�]bGOVKV[IF?cZ[I{\�EhIbRTIbZKZ[E^Z[GOV[I�]ar�I�V[@OU6U6EHB�?�U6IdEHN6]FG6NPNHIbZLZ[GOV[IOmRTIF?cZKV[I � � Va@YW�W�V[IFJLIF?hZ[@kNM@QAMVa@ODFEPG6?�Ig\�IFNPNM@Q]FGOVKV[Ib?hZ[I�\�Ed]FG6NHNPIbZKZ[GOVKIk�:EH?�]v@OJKG%\�EdW8G6NM@YV[EPDFDv@=�DFEPG6?�Ig\�E^V[IbZKZa@%\�IFNHNH@lU6EPB�?�DFEHG6?�Iy��@OJKI_�Ò]FG6NHNPIbZKZ[GOV[I � ]ar�Igj)EHIF?�IyZKVa@OJKACI_V[EPZa@l@ONHN"��IFRTI_ZKZ[EPZKGOV[IOf ¬ EH@� � JKEH@ � ' VKEHJKB�N^Za@O?�GQRTEH?�GOV[E \�IFNPNp��B�?�E^ZY`@��:Va@YW�W�V[IbJKIF?cZa@O?�\�GlB�?-@tAMVa@ODbEHG6?�Iy\�E3B�?-@ n B-@O?cZ[EPZ=`@

¹0/

Page 6: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

Z[GOZa@ONPI � IeJKG6?�GlNHIFUc@YZKEdZLVa@%NPGOV[Gk\-@ONPNHI�]FG6JKEP\�\�IbZKZ[Ig]FG6?�\�EHDFEPG6?�E�\�E�V[Ib]FEPW�V[G�]FEPZ=`@%W7I_V�EHN3ZLVa@O?�JKE^�JLZ[GOVKIO¢ � ' À��q§ ¥1� � À�q§®«z�IbV�EsZKV[@O?�JKEHJLZKGOV[E�?�GOV[Rt@ONPRTIF?cZ[IeV[IF@ONHEHDbDv@YZ[Epm�?�IbE n B-@ONHEsNM@kV[IFU6EPG6?�IQ\�E5IFRTIbZKZKEPZ[GOV[Io`ItRTG6NPZ[GW-EK`B~\V[G6Uc@YZa@l\�IbNHNHIg@ONPZLV[Ig\�B�IgV[IFU6EHG6?�E"m'JLE{r-@32«547698 � ' 8:2«547476QI;2« ö 8 � � 8:2«56f�� I]FGOVKVKIF?hZKE3À��'§iI�À��'§�JKG6?�GQ\�IFNPNp��GOVK\�EH?�I�\�E�´�2�< ¤>= ¾�?�IFEqZKV[@O?�JKEHJLZKGOV[E�@ONqJLEHNHEP]FEHG�f¯�q@T]FGOVLV[IF?cZ[IÀ�?¿W-Bq`GtIbJKJKIbV[IyEPRTRTIF\�EH@YZa@ORTIF?cZ[I�V[EH]F@/jY@YZa@T\-@ONHNPI�I n B-@ODFEHG6?�E'\�Eq·��8IbV[J����SG6NHN3@YW�W-NPEH]v@O?�\�GQNH@NHIbU6U6Iu\�E#@�EPV[]ar�r�GO¶x@OE¡?�G�\�Ep¢

À�? ¥©¨ �"À��!*�À�� � «��IFNq]v@OJKG%\�E3B�?�ZLVa@O?�JKEHJ�Z[GOV[IyÎ)Í�Î�EHNq]bEPV[]FB�E^Z[GQI n B�E^jO@ONPIF?cZ[Iy\�E3·��8IbV[J�����G6NPN�\�IbjcIyIFJKJKI_V[I

RTG�\�EP�-]v@YZ[G�mhEH?tReG)\�G�\-@�Z[IF?�I_V[I�EH?t]FG6?�JLEH\�IbVa@ODbEHG6?�I�EHN�\�EPjcIbVKJKG�JKIFU6?�Gy\�IFNPNHI¯Z[Ib?�JKEHG6?�E7I¯\�IFNHNPI]FGOVKVKIF?hZKEpÖ

� IXI n B-@ODFEHG6?�E¡\�E¡·��8IbV[J�����G6NPN®W7IbV¯B�?kZKVa@O?�JKEPJLZ[GOV[I�Î)Í�Î~\�E^jcIF?cZa@O?�G�¢���� ��� À�� ¥Ð¨ À��'§ � ��A � ����)� ¨ ´ � * � � À��'§ � ��A � $&���� ¨ ´ �À�� ¥B��' À�q§ � � A �������� ¨ ´ � ¨ À��'§ � � A ��$����� ¨ ´ � «

¬ B�NPNM@l��@OJKIg\�IFN{RTG)\�IFNPNHG%\�E�·{�7IbVKJ����SG6NHN�W8G6JKJKEM@OReGk\�Ib�-?�E^V[ITNHI n B-@YZLZKV[GkDbG6?�Ie\�E{ACB�?)�DFEPG6?-@ORTIF?cZ[GgW8G6JKJKEP�-EPNHE7W8IbV�EPN¡ZLVa@O?�JKEHJ�Z[GOV[IO¢@ �3C G6?-@�@YZKZ[EPjY@�\�EPV[I_ZKZa@m]FG6?%NM@�U6EPB�?�DFEHG6?�I���@OJKI_�ÒIFRTIbZKZKEPZ[GOV[I�W8G6NM@YV[EPDFDv@YZa@�\�E^V[IbZKZa@OReIF?hZKI�I

n B�IFNHNH@l]FG6NPNHIbZKZKGOV[I_�Ò��@OJLIgW7G6NH@YV[EHDbDv@YZa@lEP?hjcI_V[J[@ORTIF?cZ[IOf;D�B�IbJLZa@�`I�NM@l]bG6?�\�EHDFEPG6?�IT\�EdACB�?)�DFEPG6?-@ORTIF?cZ[GlW-EK`B�BZ[EPNHEHDbDv@YZa@lI n B�IFNPNM@%EH?�]FB�EdJKE{r-@O?�?�Gk�-B�G6?�IeW�VKIFJLZa@ODFEPG6?�E�\-@ONdW-B�?cZ[G\�E®jEPJLZa@�\�IFNHN"�¸@OReW-NPEP�-]v@ODFEPG6?�IOf

� �9C G6?-@o@YZKZKEPjY@lEH?cjcIbV[JK@mq]FG6?xNH@lU6EHB�?�DbEHG6?�Ie��@OJKI}�ÕIFRTI_ZKZ[EPZKGOV[I�W8G6NM@YV[EPDFDv@YZa@%EH?cjcIbV[J[@OReIF?hZKII n B�IFNPNM@Q]FG6NHNPIbZKZ[GOVKI_�Ò��@OJKIyW7G6NH@YV[EHDbDv@YZa@t\�EPV[I_ZKZa@ORTIF?cZ[IOfXØu@YZKGl]ar�IeEPN3ZKVa@O?�JKEPJLZ[GOV[Iy?�G6?Ó`IJKEPRTRTIbZLV[EH]FG�m)NHI�W�V[IFJLZ[@ODFEHG6?�E JKG6?�GeEP? n B�IFJLZ[Gg]v@OJKGgRTG6NPZ[Gy\�IFUOV[@O\-@YZ[I�VKEHJLW8IbZKZ[Ge@ n B�IbNHNHIEP?tDFG6?-@�@YZKZ[E^jO@u\�EPV[IbZLZa@XI�W8IbVKZa@O?cZ[G�E-ZKVa@O?�JKEPJLZ[GOV[E�?�G6?ejcIF?�U6G6?�G n B-@OJKE�Rt@OE-BZ[EHNPEHDFDv@YZKE�EP?DFG6?-@e@YZKZ[EPjY@yEH?cjcIbV[J[@f

] �9C G6?-@�\�E�EP?hZKIbV[\�EHDbEHG6?�IOm�]bG6? @OR��7IF\�B�I�NHISU6EPB�?�DFEHG6?�E�W8G6NM@YV[EPDFDv@YZ[ISEH?cjcIbV[JK@ORTIF?cZ[IOf²��?n B�IFJLZ[Gy]v@OJKG�NPI�]FGOVKV[Ib?hZ[E8]}r�I�@YZLZKVa@vjcIbV[J[@O?�G�EPN�ZKVa@O?�JLEHJLZ[GOVKI�JKG6?�G�IFJLZKVKIFRt@ORTIF?cZ[I¯W-EP]F]FG6NPII n B�EH?�\�E�NPG~JLZ[IbJKJKGiW-Bq`G~]FG6?�JKEH\�I_Va@YV[JKE�]FG6RTI%B�?|]FE^V[]FB�EPZKG�@YW7I_VKZ[G�fED�B�IbJLZ[G�RTG�\�Gi\�EACB�?�DFEPG6?-@ORTIF?cZ[GtW-Bq`GQIFJKJKIbVKI�BZ[EHNPEHDFDv@YZKGtEH?S@YW�W-NHEP]v@ODFEPG6?�Eq\�E'ZKEPW7Gt\�EPU6EPZa@ONPIuW8IbV�IFRyB�NM@YV[IB�?oEP?hZKIbVKV[BZKZKGOV[I�@YW8IbVKZ[G�f

¹7F

Page 7: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

\ �9C G6?-@Ó\�EuJ[@YZ[BVa@ODFEPG6?�IOm�]FG6? @OR��7IF\�B�I~NHI~U6EPB�?�DFEHG6?�E�W7G6NH@YV[EHDbDv@YZ[I~\�E^V[IbZKZ[@ORTIF?cZ[IOf³��?n B�IFJLZ[Gi]v@OJKG�NH@�]v@O\�BZ[@~\�E5Z[IF?�JKEPG6?�IlZKVa@�]FG6NHNPIbZKZ[GOVKI%Ib\|IFRTIbZLZ[EPZ[GOVKI�`I%RTG6N^Z[G�W-EP]F]FG6NH@�:W8G)]ar�E¯\�Ib]FEHRTE�\�E�jcG6N^Z � I1EPN¯]FG6ReW8GOVKZa@ORTIb?hZ[Gi\�IFN�ZLVa@O?�JKEHJ�Z[GOV[IS@OJKJKG6ReEHU6NHEH@~@ n B�IFNHNPG\�E�B�?Ó]FGOVLZ[G~]FE^V[]FB�E^Z[G�fGD�B�IFJLZKG�RTG)\�G�\�E�ACB�?�DFEHG6?-@ORTIb?hZ[GiW-Bq`G~IFJKJLIbV[IoEPReW-EHIFUc@YZKG�EP?]FE^V[]FB�E^Z[E¡\�EHU6EPZ[@ONHE7W7I_V¯IFRyB�NH@YV[IuB�?kEH?cZ[IbVKV[BZLZ[GOV[IX]ar�EPB�JKG�f

� �P�GH�*-(+*�,v,/$)(=2"üb,+2:4JIq$%*�$)É�$�,v,+2C,/.�(+$146.8É�Æ3&q$½ E�G)]F]bBW7IbV[IbRTGiGOV[@S\�IbNHNM@1\�IbZKIbV[RTEP?-@ODFEHG6?�IQ\�IFNPNHIt]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�IQÀ ¨ º \�IFNsZKVa@O?�JLEHJLZ[GOVKIÎ)Í�Î n B-@O?�\�G n B�IFJLZ[GuJKEM@�]FG6?�?�IFJKJLG�?�IFNHNH@�]bG6?�-U6BVa@ODFEHG6?�I¯@uIFReIbZKZ[E^Z[GOV[I5]FG6RyB�?�IOmcjO@ONPI¯@�\�EPVKI]FG6?xN"��IFRTI_ZKZ[EPZKGOV[Ie@o]bG6R�B�?�IgZKVa@oEH?�UOVKIFJKJKG1ItB�JK]bEPZa@m3NH@l��@OJKItJKB�NPNM@kW8GOVKZa@k\�E�EH?�UOV[IFJLJKGSITEHN]FG6NPNHIbZKZKGOV[IXJKB n B�IFNHNH@e\�EqB�JK]bEPZa@f���?oZ[@ONHI�]FG6?�-U6BV[@ODFEHG6?�I�NPI�UOVa@O?�\�IFDFDbI�\�EqEH?�UOVKIFJKJKGQJKG6?�GtNH@ºK?���IXNM@yÀ�?¯m-RTIb?hZKVKI n B�IFNHNPIu\�E¡B�JK]FE^Za@gJLG6?�GTNM@eºK���|IXNM@yÀ���f

� I¯]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�E�B�JK]bEPZa@�@�IFRTIbZLZ[EPZ[GOVKI�]FG6RyB�?�I�\�IFJK]bV[E^jcIbVa@O?�?�G n B�EH?�\�E�NM@�VKIFNM@ODFEPG6?�I�ZKV[@À��<I�ºK����m®EP?�ACB�?�DbEHG6?�Iy\�E3À�?ÐI�JK@YVa@O?�?�Gl]bG6JLZ[EPZKB�EPZ[I�\-@tB�?-@QA;@ORTEHU6NPEM@e\�Eq]FBVKjcI�JKB�NqW-EH@O?�GºK��� ¨ À���m-]FEM@OJL]FB�?-@gW7I_V�B�?k\�E^jcIbV[JKGgjO@ONPGOV[Iu\�IbNHNM@�]FGOVKV[Ib?hZ[IuÀ�?�f

��?�DFG6?-@1\�E�ACB�?�DFEPG6?-@ORTIF?cZ[G~@YZLZ[EPjY@m3JKITZKV[@OJK]FBV[EH@ORTG1NM@o]FGOVLV[IF?cZ[IQEH?cjcIbV[J[@1]ar�I%@YZKZKVa@=�jcIbV[JK@QNH@TU6EHB�?�DFEPG6?�I���@OJKI_�Ò]FG6NHNPIbZKZ[GOV[IYm8W7G6JKJLEM@ORTGt@Y¶8IbV[Rt@YVKI�]ar�I�NH@T]FGOVKV[Ib?hZ[Iy\�E']FG6NHNPIbZKZ[GOV[IT`IJKG6JLZ[@O?�DFEM@ONPRTIF?cZ[ITW�@YV[E5@ONPNM@kW7GOVKDFEHG6?�IQ\�E n B�IFNHNH@S\�EsIFRTIbZKZKEPZ[GOV[Ie]}r�IQr-@SJKBW7I_Va@YZ[GSNM@o��@OJKIO¢À�� ¥ ¨(� ' À���fo����IFJLW�V[IbJKJKEHG6?�IQ\�IFNPNM@o]FGOVLV[IF?cZ[IQ\�E���@OJKItV[EPJKB�NPZa@ n B�EH?�\�E"m�\-@ONHNp��@YW�W-NHEP]v@ODFEHG6?�I\�IFN¡W�V[EH?�]bEPW-EHGg\�E#@uE^V[]ar�r�GO¶x@OE®?�G)\�E"m

À�? ¥©¨ �"À��L*ÓÀ�� �d¥©¨ ��´ ¨ � '{� À��«¬ G6JLZ[E^Z[B�IF?�\�G�?�IFNHNH@�W�VKIF]FIF\�IF?cZ[IiI n B-@ODFEPG6?�I�@�À��µNM@xJKB-@�IFJLW�V[IFJLJKEHG6?�IiEH?<ACB�?�DFEHG6?�I�\�E�À��GOZKZ[Ib?�EM@ORTG

À? ¥ ��´ ¨ ��'�� À��� ' -n B�EP?�\�E

À�� ¥ � '´ ¨ � ' À�? ¥NMO' À�? -

\�G/jcI MK' `Iu\�I_�-?�EPZ[GT]bG6RTI MK'�¥ ��'´ ¨ � '

IF\S`I¯\�E�JKG6NHE^Z[G�EP?�\�EH]v@YZ[GX\-@OE8]FG6JLZLV[BZKZ[GOV[E�]FG6RTIQP ' �¿�"JKE8?�GOZKE�]ar�I�EHN-W7Ib\�EH]FISRBT `I�Rt@OEPB�JK]FG6NHGI n B�EH?�\�E n B�IbJLZ[GeW�@YVa@OReIF?hZLV[Ge?�G6?o\�I_jcIXIFJKJLIbV[I�]FG6?�ACB�JLGt]FG6?UP,V�W�]ar�I�J[@YVY`@�EH?cZKV[G�\�GOZKZ[GgW-EK`B@vjO@O?cZ[E¡I�@vj)VY`@�Z[BZKZF�¸@ONPZLV[GgJLEHU6?�EP�-]F@YZ[G � f

¬ I MK' ACG6JKJLI�EP?�\�EPW8IF?�\�IF?cZ[Iu\-@ON�jO@ONPGOV[I�\�E7À���mJKB�N7W-EH@O?�G�\�IbNHNHI�]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I�\�E®B�JK]FE^�Za@�JKE�GOZKZ[IbVKVKIb���7IbVKG�\�IFNHNPI%VKIbZKZ[I%W�@YVa@ONHNPIFNHI%IF\|I n B�EHJLW�@ODbEM@YZ[IOf���?ÓV[Iv@ON^ZY`@ MO' r-@�B�?-@~]FIbVLZa@\�EPW8IF?�\�IF?�Dv@o\-@%À���m W8IbVX]bB�E{NPIg]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�Ig?�G6?�JLG6?�GkI n B�EHJLW�@ODFEH@YZ[IOfy��?�G6NPZKV[I�IFJKEPJLZ[I�EHN

¹0X

Page 8: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

]FG6JKEP\�\�IbZKZ[G¯Ib¶7IbZLZ[G�·�@YVKNZYcmY]bG6?�JKEHJLZKIF?hZKI�?�IFNHNH@�V[EP\�B�DFEHG6?�I�\�IbNHNM@�NM@YV[U6r�IbDFDv@�IbÙe]v@O]FI�\�IFNPNM@�VKIFU6EHGY�?�I�\�Ed��@OJLIT@ONHN"�¸@OB�RTIb?hZa@YVKI�\�IFNHNH@%W7G6NH@YV[EHDbDv@ODFEHG6?�I�EH?cjcIbV[JK@l\�IFNPNM@lU6EPB�?�DFEHG6?�Iy��@OJKI_�Ò]FG6NHNPIbZKZ[GOVKIIXEPN']bG6?�JKIFU6B�IF?cZ[I�IFJLZKIF?�\�IbV[JKEq\�IFNHNH@eDFG6?-@T\�E JLjB�GOZa@OReIF?hZKGgV[IFNH@YZ[EPjY@e@�Za@ONHIuU6EHB�?�DFEPG6?�IOf�>�?-@V[EP\�B�DFEHG6?�I�\�IFNHNH@%NPB�?�U6r�IFDFDv@l\�E3��@OJKI�W8GOVKZa@%@%B�?-@QV[EH\�GOZLZa@QVKEH]FG6R��-EH?-@ODbEHG6?�IyI n B�EH?�\�E{@QB�?EH?�]_V[IFRTIF?cZ[Gu\�IFNHNH@X]FGOVKV[Ib?hZ[I�\�E-]FG6NHNPIbZKZ[GOV[IYf�z�IbVKZa@O?cZ[G�mcW7IbV�jO@ONPGOV[E�\�E7º,��?¿�"I n B�EP?�\�E�\�E�ºK��� �W-EK`BQIFNPIbjY@YZ[E7NM@�]bGOVKV[IF?cZ[I�\�E7]FG6NPNHIbZKZKGOV[I�@OB�RTIF?cZa@�@�W�@YV[E^ZY`@�\�E7]FGOVKVKIF?hZKI�\�E���@OJKI�I n B�EH?�\�E�]FEM@=�JK]FB�?-@l\�IFNHNPIe]FBVKjcIg]FGOVKV[EPJLW7G6?�\�Ib?hZ[E�@ONHNPIg]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�Ig\�EdB�JK]FE^Za@lV[EPJKB�NPZ[@lEH?�]bNHEH?-@YZ[@QjcIbVKJKGNp��@ONPZ[G�f

Øy�¸@ON^ZKV[G%]v@O?cZ[G�m W8IbVXjY@ONHGOVKE�\�EdZKIF?�JKEHG6?�ITºK��� EH?�ACIbVKEHGOV[E{@oº"[1NM@QU6EHB�?�DFEPG6?�Ie]FG6NPNHIbZLZ[GOV[I_���@OJKI�?�G6?�`I�W-EK`B1W7G6NH@YV[EHDbDv@YZa@eEP?hjcIbVKJ[@ORTIF?cZ[I�IOm7W8IbVuºK���¿JKBÙe]FEHIb?hZ[IbRTIF?cZ[I���@OJKJ[@�� n B-@ONP]ar�I\�IF]FEPRTGy\�E7jcG6NPZ � JKE®IF?cZKVa@yEH?QW-EHIF?-@yJ[@YZ[BVa@ODbEHG6?�IOfd��?l]FG6?�\�EPDFEHG6?�I�\�E7J[@YZKBVa@ODFEHG6?�I�JKE8W8IbV[\�I�EHN]FG6?cZKV[G6NPNHG�\�IFNPNM@�À���\-@¯W�@YVKZ[I5\�IFNPNM@�À�?~I�ZKBZKZ[I5NHIs]v@YVa@YZKZ[I_V[EHJLZKEH]ar�I�Z[IF?�\�G6?�G�@�JKG/j)Va@YW�W8GOV[JKEpÖ6EP?n B�IbJLZa@�]bG6?�\�EHDFEPG6?�I�EHN6]FG6RgW7GOVKZa@OReIF?hZKG�\�IFNcZKVa@O?�JLEHJLZ[GOVKI�\�E^jcIF?hZ[@¯ACGOVKZ[IFReIF?hZKI�?�G6?�NPEH?�Iv@YVKIOfq��?�-U6BVa@�Va@YW�W�V[IbJKIF?cZ[EM@ORTG�N"�¸@O?�\-@ORTIb?hZ[G¯\�IFNHNPI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I5\�E)B�JL]FEPZa@�@�IbRTIbZKZ[E^Z[GOV[I�]FG6RyB�?�IW7I_V�B�?kZKV[@O?�JKEHJLZKGOV[IuÎ)Í�Î \

]^^^`_>a^ _>b^ _dc^ _fe^ _dg_>h_>i_dj^

k%l

k

`·©W8G6JKJKEP�-EPNHITjcIF\�I_V[IQ]}r�IYm{W�V[G6NPB�?�Uc@O?�\�G1jcIbV[JKG�JKEH?�EPJLZKVa@o]bG6?�\�IFNPNHITV[I_ZKZ[ItNHIt]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I\�E�B�JK]bEPZa@�]FG6JLZKVKB�EPZ[ISBZ[EPNHEHDbDv@O?�\�G�ºK?��µ]FG6RTIoW�@YVa@ORTI_ZKV[GxEH?cjcIF]FI�\�E�À�?�m�Z[BZLZ[IoZa@ONHE�V[IbZKZKIEH?cZ[IbVKJKIF]v@O?�GxN"�¸@OJKJKI%\�IFNPNHIo@OJL]FEHJKJLIkEH?�B�?�G�JLZ[IbJKJKG~W-B�?cZ[Gx]ar�Ik]FGOVLV[EHJLW8G6?�\�I1@ONHNH@�]bG6JKEH\�\�IbZLZa@��Z[IF?�JLEHG6?�IX\�E¡·s@YV[NZY)��m�EH?kU6Ib?�IbV[IX]bG6ReW�V[IFJ[@yZKVa@ ¨ / 2�I ¨ ´�272�¼yf

m

n

oqp

o m mmmm>rtsvurtstwrtsyxrzsy{rtsz|

� IX]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�Iu\�E EP?�UOV[IFJKJLGQ@gIFRTI_ZKZ[EPZKGOV[I�]FG6RyB�?�IuVa@YW�W�V[IbJKIF?cZa@O?�GtNM@yV[IFNM@ODbEHG6?�IuZLVa@gÀ�?I�ºK?��ÐEH?1ACB�?�DbEHG6?�I�\�IFNHNH@QºK����f�·�JKJKI�Va@YW�W�V[IbJKIF?cZa@O?�GkEPNq]FG6ReW8GOVKZa@ORTIb?hZ[Gg\�IFNHNH@tU6EHB�?�DFEPG6?�I��@OJKI_�ÒIFRTIbZLZ[EPZ[GOVKI�Iir-@O?�?�G n B�EH?�\�E�B�?ÿ@O?�\-@ORTIF?cZ[G�IFJLW8G6?�IF?�DFEM@ONPI~JKEPRTEHNPI�@ n B�IbNHNHG�\�E�B�?\�EHG�\�G�Ö�V[EPJKIF?cZ[G6?�G�EH?�G6NPZLV[IQ\�IFNHN"��Ib¶8IbZKZ[GS·�@YVKNZYcf1��?�W�@YVKZKEH]FG6NH@YV[IOmdJKIQJKE�EP?�]bV[IFRTIb?hZa@iºK����mdNH@NHB�?�U6r�IbDFDv@�\�E)��@OJKI�\�EPRTEH?hB�EHJL]FIOm6]v@OB�J[@O?�\�G�B�?-@�RTEP?�GOV[I�V[EP]FG6R��-EH?-@ODFEPG6?�I�IOm6\�E�]FG6?�JKIFU6B�IF?�DF@mB�?-@�\�EHRTEP?�B�DFEPG6?�I�\�IFNHNH@�]FGOVLV[IF?cZ[I�\�E��@OJLIOfd��IFNHNH@��-U6BV[@�JKGOZLZ[G6JLZa@O?cZ[I�JKG6?�G�Va@YW�W�V[IFJKIb?hZa@YZKI�NPI

¹ 6

Page 9: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

}>~���t����)���}� �v� ~ �)����v� ~�

�� ~

]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�E¡EH?�UOV[IFJLJKGT@yIFRTIbZLZ[EPZ[GOVKI�]bG6R�B�?�I�W8IbV�B�?%ZKVa@O?�JKEPJLZ[GOV[I�Î)Í�ÎiIb\x`I�W7G6JKJKE^�-EHNPIjcIF\�IbVKIX]ar�EM@YVa@OReIF?hZKIXEHN7VKEHJKB�N^Za@YZ[G�\�IFNHN"��Ib¶8IbZKZ[Gg·�@YV[N�Ycf� I�]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I�\�E3EH?�UOV[IbJKJKG%I�\�E�B�JK]FEPZ[@Q\�IbEqZKVa@O?�JKEPJLZ[GOV[E�Í�Î)Í~JLG6?�Gl\�IFN'Z[BZKZ[G%@O?-@ONHG6U6r�I�"]FG6?�U6NHE�GOW�W7GOVLZ[B�?�E�]v@OR��-EM@ORTIF?cZ[E5\�E�JKIFU6?�G � @ n B�IFNHNPIl\�IFU6NPE�Î)Í�Î�f � @ONHE�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�IOmV[E^W7GOVKZa@YZKI�\�EcJKIFU6B�E^Z[G�mYJLEhGOZLZ[IF?�U6G6?�G¯\-@ n B�IFNPNHI{W�V[IFJKIF?cZa@YZ[I{W7IbVqE6ZKVa@O?�JKEPJLZ[GOV[EcÎ)Í�ÎeJLG6JLZ[EPZKB�IF?�\�GÀ�?�]FG6? ¨ À�?¯m�º,?���]FG6? ¨ ºK?���m�ºK����]FG6? ¨ ºK����m-À���]FG6? ¨ À���IuÀ��|]FG6? ¨ À���f

����5��"�

��y�

����J��������J�

����J��5��5��5��5��5�����5�

������¡ £¢�¤ £¢¥¦>§

¥)¨¦¤©© ¨�ª �¤«£¢© ¨�ª© ¨�ª

¹ 4

Page 10: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

¬���������s ����������s8�T� ��­y�¡�)���¯®��±°®�³²µ´��¶8�"!�#%$&'$)(+*-,/.�(+$1032546.�(+(+$&7,/$146.8&7,/(+.89:9;*-,/.�2"&�,/$&3üv2;.�&q$��IFE�ZKVa@O?�JLEHJLZ[GOVKE�@�Ib¶7I_ZKZ[G�\�E-]v@OReW8G�mc]FG6RTI�JKB�U6U6IbV[EPJK]FI�EPN�?�G6ReI�JLZKIFJKJKG�mhEHN��-B�JKJKG�\�E-]FGOVLV[IF?cZ[IjEPIF?�I�]FG6?hZLV[G6NHNH@YZ[GgZKV[@ORTEPZ[I�B�?k]v@OReW7G�IFNPIbZKZKV[EP]FGeIYm n B�EH?�\�E"m�@YZLZKVa@vjcIbV[JKGgEHN®jO@ONPGOV[I�\�IFNHNH@�Z[IF?)�JKEPG6?�Iy@YW�W-NHEH]F@YZa@Q@TB�?iGOW�W8GOVKZ[B�?�GQIFNHI_ZKZKV[G�\�Gt\�E3]FG6Rt@O?�\�G�f�z�IbVLZa@O?hZKG�m7]FG6J�` ·3]bG6RTI�?�IFN3]F@OJKG\�IFE®��� � @/jcIbjY@ORTG�EP?hZLV[G)\�GOZKZKG�B�?-@�Va@YW�W�V[IFJKIb?hZa@ODbEHG6?�I�EH\�Iv@ONPEHDFDF@YZa@�\�IFN8ACB�?�DbEHG6?-@ORTIF?cZ[G�W7I_VRTIFDbDFGi\�E5B�?ÓU6IF?�IbVa@YZ[GOVKI%\�E�]FGOVLV[IF?cZ[Il]bG6?hZKVKG6NHNM@YZKGiEP?�]FGOVLV[IF?cZ[IOm�W8IbVgNHG�JLZ[B�\�EHGi\�IFE�ZKVa@O?)�JKEPJLZ[GOV[Es@SI_¶7IbZKZKG�\�Es]v@OReW7G1EP?hZLV[G)\�B�]FEH@ORTGoEPNs]FG6?�]FI_ZKZ[G�\�EsU6IF?�IbV[@YZ[GOV[IQEH\�Iv@ONPIt\�Es]FGOVLV[IF?cZ[I]FG6?cZKV[G6NPNM@YZ[G�EH?%Z[IF?�JKEPG6?�IOm�NH@g]FB�E®Va@YW�W�VKIFJKIF?cZa@ODFEPG6?�I�]FEPVK]FB�EPZa@ONPIe`I�EH?�\�EP]v@YZa@gEP?l�-U6BVa@f

�'@ n B-@O?hZ[E^ZY`@¹¸7º V[@YW�W�V[IFJKIF?cZa@ÓEPN¯Va@YW�W8GOVKZ[G�ZKVa@�NM@�]FGOVKV[IF?cZ[Ii\�E�B�JK]FEPZ[@�ISNM@xZ[IF?�JKEPG6?�IiEP?EH?�UOVKIFJKJKG�fdØ�EHRTIb?�JKEHG6?-@ONPRTIF?cZ[IX`I n B�EH?�\�E�Np��EP?hjcI_V[JKG�\�E8B�?-@XVKIFJKEHJ�Z[IF?�Dv@�IF\S`I�IFJ�W�V[IFJKJ[@�EP?t¾¼»=¼G�m�W-EK`Bl]FG6RyB�?�IFRTIF?cZ[IOm-EH?kRT¾¼»=¼yf

z�G6JKJLEM@ORTGÓ@O?�]}r�IxEP? n B�IbJLZ[G|]v@OJLG|Va@YW�W�V[IFJKIb?hZa@YVKIxNHI~]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I�\�EuB�JL]FEPZa@m�JKB�NW-EM@O?�G��O }� £  Ym�GOZKZ[Ib?�IF?�\�G�B�?-@xA;@ORTEPU6NHEH@i\�E�]FBVLjcI1EH?�ACB�?�DFEHG6?�IS\�IFN�W�@YVa@ORTIbZKVKG�]FG6JLZ[E^Z[B�EPZKG\-@ONHNH@gZ[IF?�JLEHG6?�I�\�E'EH?�UOV[IFJLJKG�f � @ONHE ]FBVKjcI�@ON^ZKV[GT?�G6?1JLG6?�Gt]}r�IuV[IbZKZ[IuW�@YVa@ONHNPIFNHIX@ONHNp��@OJKJKIu\�IFNHNPI@OJK]FEPJKJKIOm-W7G6EP]ar�wIuNH@g]FGOVKVKIF?hZKIXEH?lB�JK]FE^Za@g?�G6?o\�E^W7IF?�\�Iu\-@ONHNH@yZ[Ib?�JKEHG6?�Iu�6 Ym-Rt@yJKG6NPZa@O?cZ[G�\-@ONHNH@� ¤ f{z�IbV n B�IbJLZ[GgZKEPW7Gy\�E¡U6IF?�IbV[@YZ[GOV[I�]FG6Rt@O?�\-@YZ[GyW7G6JLJKEM@ORTG�W8IF?�J[@YV[Iu@�B�?-@�]FG6?�-U6BVa@ODFEPG6?�IEH?~]FB�EsJKG6?�GlW�V[IFJKIF?cZ[E�B�?~U6IF?�IbVa@YZ[GOVKIT\�Es@ONPEHRTIb?hZa@ODbEHG6?�I�IFJLZ[IbVK?�G�º8 [ gIgB�?-@kV[IFJKEPJLZ[IF?�Dv@o\�E]v@YV[EP]FGe¦�ªqm-]FG6ReI n B�IFNHNH@yVa@YW�W�VKIFJKIF?cZa@YZa@T?�IFNPNM@y�-U6BVa@gJKGOZLZ[G6JLZa@O?cZ[IOf

`·xW7G6JKJLEP�-EHNPI�ZLVa@O]F]FEH@YV[I�JKB�N�W-EM@O?�GX\�IbNHNHI�]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�E-B�JK]FEPZ[@uB�?-@�VKIbZKZa@�\�E�]v@YV[EH]bG�m�NH@�]FB�EW7Ib?�\�IF?�Dv@t]FGOVKV[EPJLW7G6?�\�Iy@ ¨ ´+­Y¦�ª~I�]ar�I�EP?hZKIbV[JKIF]F@QN"�¸@OJKJLIX\�IFNPNHI�@OJK]bEHJKJKIXEH?1]FGOVKVKEHJLW8G6?�\�IF?�Dv@\�E'º8 [ Ym-]FG6RTI�EP?�\�EH]v@YZ[GgJKB�NHNPIX]v@YV[@YZKZ[IbV[EPJLZ[EP]}r�I�\�E¡JKIFU6B�E^Z[GgVa@YW�W�VKIFJK?�IbZa@YZKIOf¾�N�jO@YVKEM@YV[I�\�IFNHNH@�Z[IF?�JLEHG6?�I�� ¤ @YW�W-NHEP]v@YZa@XEP?eEP?�UOV[IFJKJKG�m�EHN�W-B�?cZ[G�\�E�NH@/jcGOVKGXJKE-JLW8G6JLZ[IbVY`@ n B�EH?�\�ENHB�?�U6GgNM@�V[IbZKZ[@g\�E¡]v@YV[EP]FG�m-\-@O?�\�GeNHB�G6U6Ge@�B�?-@�jO@YV[EH@ODFEHG6?�I�\�IFNPNM@�Z[IF?�JKEPG6?�IX\�E¡B�JK]FE^Za@g�O �]ar�IVa@YW�W�V[IbJKIF?cZa@lB�?-@TV[IbW-NPEH]v@Q@OReW-NPEP�-]v@YZ[@TI�EH?cjcIbVKZ[E^Za@t\�E3A;@OJKIy\�IFNHNH@TZ[IF?�JKEPG6?�I�\�EqEH?�UOV[IFJLJKG�f ¬ INHI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I�ACG6JKJLIbV[G�I n B�EHJLW�@ODFEH@YZ[I�]FG6ReI n B�IFNHNPI�Va@YW�W�V[IbJKIF?cZa@YZ[I�EH?T�-U6BV[@m)NM@�Z[IF?�JKEPG6?�I\�E�B�JK]FE^Za@SW�VKIFJKIF?cZ[IbV[I_���7I1B�?-@�VKIFNM@ODFEPG6?�ItW7IbV[ACI_ZKZa@ORTIF?cZ[I%NHEP?�Iv@YV[I%]FG6? n B�IFNHNH@�\�E5EP?�UOV[IFJKJKG�ÖjcIF\V[IbRTG�]ar�I�EP?<VKIv@ONPZY`@�E�\�EHJLW8G6JKEPZKEPjE�@�Ib¶7I_ZKZ[GÓ\�E�]v@ORgW7G�JKG6?�GÓ]v@YV[@YZKZ[IbV[EPDFDv@YZ[E�\-@�B�?-@

ö 2

Page 11: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

\�EPW8IF?�\�IF?�Dv@ n B-@O\Va@YZ[EH]F@l\�IFNPNM@k]FGOVLV[IF?cZ[IT\�E{B�JK]FEPZ[@k\-@ONHNH@lZ[IF?�JKEPG6?�IT\�E{EH?�UOV[IFJLJKG�m'W8IbV�]FB�E{EHNNHGOVKGe]FG6ReW8GOVKZa@ORTIb?hZ[G�W-Bq`GT]bG6?�JKEH\�IbV[@YV[JKE NHEH?�IF@YV[IuJLG6NHGgW8IbV�W-EH]F]FG6NPE¡JKIFU6?-@ONHE"f¶8�;ÂiÃF9s,/(+*�&3üv2:üb,/.�(+$Sþ¾½À¿�{��EH\�IF@�@ONPNM@5��@OJKI�\�IbNhACB�?�DbEHG6?-@ORTIF?cZ[G�\�IFN6ZKVa@O?�JKEPJLZ[GOV[IÁ�U ¬ �v�SIbZa@ON �>ÂÄÃ�EH\�I}� ¬ IFRTEP]FG6?�\�B�]bZ[GOV �`I�@Y����@OJLZa@O?�DF@�JKIbReW-NHEP]FIO¢�JKE7]_V[Iv@�B�?�GyJLZKVa@YZ[Gy\�E�]v@YV[EH]ar�I�RTGO�-EPNHE�EH?tW�V[G6JKJKEPRTEPZ=`@�\�IFNHNH@�JKBW7IbV���-]FEPIe\�E{B�?�JKIFRTEP]FG6?�\�BZKZ[GOVKIOm'ZKV[@ORTEPZ[IyN"�¸@YW�W-NHEP]v@ODFEPG6?�Ig\�E{B�?�]v@OReW8GkIFNPIbZKZKVKEH]FG�m¡W7IbVXRTIFDFDbG\�E5B�?�IFNHIbZLZKV[G)\�G�\�E5Uc@YZ[ItRTI_Za@ONHNPEH]FG�m�]ar�IÓ�K@YZKZ[EPV[@O�1NHIQ]v@YV[EP]}r�IQjcIbV[JLGiNH@SJLBW7IbVK�-]bEHIkJ�Z[IFJKJ[@f>�?-@i\�IbJK]bV[EPDFEHG6?�I1@YW�W�VKGOW�V[EM@YZa@�\�IFN�ACB�?�DFEHG6?-@ORTIb?hZ[G~\�IFN�ZLVa@O?�JKEHJ�Z[GOV[I3�U ¬ V[EP]}r�EPIF\�IbV[I_���7I]FG6?�]FI_ZKZ[E @/jY@O?�Dv@YZ[E¡\�E¡RTIF]b]v@O?�EH]v@ n B-@O?cZ[EHJ�Z[EH]v@y]ar�I�IFJKB�NH@O?�Ge\-@ n B�IFJLZ[@�ZKVa@YZLZa@ODFEHG6?�IYm n B�EH?�\�EJKAMV[BZLZ[IbV[IFReGoB�?-@o\�IFJK]bVKEHDFEPG6?�ITEH?cZ[B�EPZKEPjY@m3@O?�]FGOV[]arswIT?�G6?�VKEHU6GOV[G6J[@m¡W7I_V�JLjcG6NHU6I_V[IeNPGkJLZ[B�\�EPG\�IFN£�U ¬ f�'@yJ�ZKV[BZKZ[BV[@�\�E7B�?tZ[EPW-EP]FG�ZKVa@O?�JKEPJLZ[GOV[IS�U ¬ @�]F@O?-@ONHI�Îx`I�Va@YW�W�V[IbJKIF?cZa@YZa@y?�IFNHNH@�-U6BVa@�JKIFU6B�IF?cZ[IO¢�EH?%B�?l�-NHG�]F]FGg\�E®JKEHNPEH]FEPG�ÍkjcIF?�U6G6?�GgVKIv@ONHEPDFDv@YZ[IOm-@yB�?-@g]bIbVKZa@y\�EHJLZ[@O?�Dv@�ZKV[@NHGOVKG�m6\�B�I�\�E^¶7B�JKEPG6?�E�\�EZ[EPW8G�Îl]ar�I5Va@YW�W�V[IbJKIF?cZa@O?�G�U6NHE�IFNHI_ZKZKV[G�\�E\�E�JKG6BV[]FI�I�\�E�\Va@OEP?®ÖhJLGOW�Va@NM@�JKBW8IbVK�-]FEPIX\�IFN®JLEHNHEP]FEHGyjEPIF?�I�GOZKZ[IF?hBZ[G�B�?lJLGOZKZ[EHNPI�JLZKVa@YZ[Gy\�E®G6JKJLEH\�G�\�E®JKEHNPEH]FEPGo�"\�IbNHNp��GOV[\�EH?�I\�IFNPNM@y\�IF]FEH?-@g\�E®?-@O?�G6RTIbZKV[E®G�mW-EK`BlV[Ib]FIF?cZ[IFRTIF?cZ[IOm�\�IFE¡?-@O?�G6RTIbZLV[E � ]ar�IXACB�?�U6Iu\-@gEPJKG6NM@O?cZ[IOÖ@ON3\�E3JLGOW�Va@%\�IbNHNHGQJLZLVa@YZ[GQEHJKG6NH@O?hZKI�IyZLVa@tJKG6BV[]FIyIy\Va@OEH?SjEPIF?�I�V[Iv@ONPEHDFDF@YZ[GQB�?�GlJLZLVa@YZ[GQRTI_�Za@ONPNHEH]bG��"GlW-E[`B~V[Ib]FIF?cZ[IFRTIF?cZ[IT\�EdJKEPNHEP]FEHG%W7G6NHEP]bV[EPJLZa@ONHNPEH?�G%ACGOVKZ[IFReIF?hZKIe\V[G6Uc@YZ[G�m EH?~RTG)\�G%\-@V[IF?�\�I_V[NHGT]bG6?�\�BZKZ[GOV[I � ]ar�IXACB�?�U6IX\-@gUc@YZ[IOf

¬ IeJLEs@YW�W-NPEH]v@%B�?-@lZ[IF?�JKEPG6?�IgW8G6JKEPZ[E^jO@l@ONdUc@YZ[I�VKEHJLW8IbZKZ[G1@ONdJKEPNHEP]FEHG�Í�JKGOZKZKG6JLZa@O?cZ[IOm¡jcIF?�U6G6?�GV[EP]}r�EH@ORt@YZ[E{IFNHI_ZKZKV[G6?�E�EP?xW�V[G6JKJKEPRTEPZY`@l\�IFNHNH@SJLBW7IbVK�-]bEHIOm{]FG6JKEP]F]ar�wIlJKE�r-@mdEH?�B�?�JLGOZKZ[EHNPEHJKJLEHRTGJLZKV[@YZ[GkJKB�-E^Z[GkJLGOZKZ[GkNH@lJKBW8IbVK�-]FEPITJLZ[IbJKJ[@mqB�?xACIb?�G6RTIF?�Gk\�E{EH?cjcIbV[JLEHG6?�IO¢uEHNdJKEHNPEH]FEPGl\�E^jcIF?cZa@NHG�]v@ONHReIF?hZKI�\�E�Z[E^W7GXÎ�m�\-@O?�\�G n B�EP?�\�E�NPB�G6U6G�@ONPNM@uACGOVKRt@ODFEHG6?�I�\�E-B�?t]v@O?-@ONHI�]FG6?�\�BZKZ[GOVKI¯]ar�I

ö ´

Page 12: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

RTIbZLZ[I�EH?e]bG6?�?�IFJKJKEPG6?�I¯JKG6BV[]bI¯I¯\V[@OEH?®f3��NZKVa@O?�JKEPJLZ[GOV[IÅ�U ¬ r-@�W7I_V[]FE�`G ö IFNPIbZKZKVKG)\�Ep¢qJKG6BV[]FIOm\Va@OEP?®m6Uc@YZ[I5I�EHN n B-@YVKZ[G�m6\�IF?�G6ReEH?-@YZ[G��-B�N^Ñ7m6]ar�I�]FGOVKV[EPJLW7G6?�\�I�@ONJKEPNHEP]FEHG�\�EJLB�-JLZKVa@YZ[G�m n B�IFNHNPG?�IFN n B-@ONHI�JKEqACGOV[Rt@tEHN']v@O?-@ONHIOf���IFEq\�EHJLW8G6JKEPZ[E^jE��Æ ¬ ?�G6?SEP?hZ[IbUOVa@YZ[E3N"��IFNPIbZKZKV[G�\�Gt\�Eq�-B�NPÑx`I\�E¡JKG6NHE^Z[G�EH?cZ[IbV[?-@ORTIb?hZ[Iu]FG6NHNPIFUc@YZ[Gg@ON¡JKG6BV[]FIOf

��N5]v@O?-@ONPIl\�E5W7GOVLZa@YZ[GOV[E�ReEH?�GOV[E^Za@YV�Ç·s]bG6RTEH?�]FEH@i@SACGOV[Rt@YVKJKE�@ONHNH@SJLBW7IbVK�-]bEHI n B-@O?�\�G~NH@Z[IF?�JLEHG6?�IiZLVa@ÓUc@YZ[I�Ii�-B�N^Ñ¿JLBW7IbVa@|B�?¿jO@ONPGOV[Ii\�E�JKG6U6NPEM@�EP?�\�EH]v@YZKGÓ]FG6? º"Èsfµz�G6EH]ar�wI~?�IFE\�EHJ�W7G6JKE^Z[EPj)E \�EPJK]bV[I_Z[EqEPN¡�-B�N^Ñ~`IX\�E'JKG6NPEPZ[Gg]FG6NHNPIFUc@YZ[Gg]FG6?1EHN¡JKG6BV[]bIQ�"]FG6RTIuJKGOW�Va@T@O]b]FIF?�?-@YZ[G � mNM@oZ[Ib?�JKEHG6?�ItZKVa@1Uc@YZ[IQIT�-B�N^Ñ�]FGOVKV[EPJLW7G6?�\�IQ]FG6?�NM@�ºKÉ'§ÓIt]FG6RTITZ[@ONHItNM@1EP?�\�EH]ar�IbV[IFReGi?�IFNJKIFU6B�E^Z[G�f `· EPReW7GOVKZ[@O?hZ[I%JKGOZKZKG6NHEH?�IF@YV[Ik]ar�I1NM@�Z[IF?�JKEPG6?�ISº,ÈÏW7IbVtEÅ�U ¬ ?�G6?�r-@�?hB�NHNH@x@]ar�IeA;@YV[Ig]FG6?~NH@kº"È�]}r�Ie@Y���-EM@ORTG%]FG6?�JKEP\�IbVa@YZ[Gl?�IFNHNPGkJLZKB�\�EHGk\�IbEs��� � �:W�@YV[E{@LÊ0Ë�­JÌ � ¢�NH@]FG6EP?�]FEH\�IF?�DF@�\�IbE?�G6RTE�`I�\�IFN)Z[BZLZ[G�ACGOVKZ[B�E^Za@f3z�IbVqjO@ONPGOV[E�W-EP]F]FG6NHE7�"EH?�ACI_V[EHGOV[E�@ n B-@ONP]ar�I5\�IF]FEHReG\�EcjcG6NPZ � \�IFNHNH@�ºK�§ mYEHNc]v@O?-@ONHIs\�IFNhZLVa@O?�JKEHJ�Z[GOV[I³�U ¬ r-@¯B�?y@O?�\-@ORTIF?cZ[G�B�?�EPACGOV[RTI�ZLVa@�JKG6BVK]FIIX\V[@OEH?®m8]bG6?oB�?�GtJLW7IbJKJKGOV[IOm�IX]FG6?�JLIFU6B�IF?cZ[IFRTIF?cZ[I�B�?-@T]FG6?�\�B�]bEP�-EHNPEPZY`@m�]ar�I�]bV[IbJK]FIbVa@O?�?�G%@ON]bV[IbJK]FIbV[I�\�IFN�\�IbNHNM@�º,Éq§¡f ��? n B�IFJ�Za@x]FG6?�\�EHDFEPG6?�ISEHNÍ�U ¬ W-Bq`G n B�EP?�\�E�IFJKJKI_V[ISBZ[EHNPEHDFDv@YZKG]FG6RTI%B�?-@iV[IbJKEHJLZKIF?�Dv@~jY@YV[EM@Y�-EPNHIOm�]bG6?hZKVKG6NHNM@YZ[@SZKV[@ORTEPZ[IQNH@iZ[IF?�JKEPG6?�I1º,Éq§¡m�\-@O?�\�G�NHB�G6U6G�@]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�NHEP?�Iv@YV[E¡JKB�N¡W-EM@O?�Gtº,��� ¨ À���f

Î�ÏÑÐÒ

Ð Ò�Ó

Ð Î&ÔÄÐ ÐÖÕ Ó Î�×ÄÐÐ Î�Ø(ÐÐ Õ ÓÕ Ó

Õ ÓÙ

¬ I1º,s§ÿ`I%Rt@OU6U6EHGOV[IQ\�E n B-@ONP]ar�Ik\�IF]FEPRTG~\�E�jcG6NPZFmsEHN5]bG6ReW7GOVKZ[@ORTIF?cZ[Gi\�IbN�]v@O?-@ONPIl?�G6? `IW-EK`B n B�IFNPNHG%\�E�B�?-@QV[IFJKEPJLZ[IF?�Dv@oNPEH?�Iv@YVKIOm W8G6EH]arswIeN"�¸@OReW-EPIFDFDv@tjcIbVKZKEH]v@ONPIg\�IFNPNHGlJLZ[IFJKJLGkjcIbVKVY`@k@\�EPW8IF?�\�IbV[I%\-@ONHNH@oW7G6JKEPDFEHG6?�IQ]FG6?�JKEP\�IbVa@YZa@1ZKVa@1JKG6BVK]FIQI%\V[@OEH?®md]FG6RTITVa@YW�W�VKIFJKIF?cZa@YZ[Gi?�IFNHNH@�-U6BVa@eJLIFU6B�IF?cZ[IOf

�{��Ib¶8IbZKZ[E^jO@�Z[IF?�JLEHG6?�I�ZKVa@�Uc@YZ[I�I�JKB�-JLZKV[@YZ[Gg\�E^W7IF?�\�I�\-@ONHNH@�W7G6JKEPDFEHG6?�I�NHB�?�U6GyEPN7]v@O?-@ONHIY¢{JK@YVY`@W�@YV[E�@�º,Éq§TEP?T]FGOVKV[EPJLW7G6?�\�Ib?�Dv@X\�IFN�JKG6BV[]FI�I¯\�EPRTEH?hB�EPVY`@�@vj)jEP]FEH?-@O?�\�G6JLE�@ON�\V[@OEH?®f ¬ I�º,Éq§ ¨

öhÔ

Page 13: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

ºK�§�Ú¿º"È�IFJLEHJLZ[I_VY`@TB�?oW-B�?hZKGtEH?o]FB�E'NM@gZKIF?�JKEHG6?�IuZKVa@eUc@YZ[I�I�JKB�-J�ZKVa@YZ[GTV[EPJKB�NPZ[@�W�@YV[E'@Qº,È�"NH@�ZKIF?�JKEHG6?�I�\�E®JKG6U6NPEM@�W7I_V�NH@�ACGOV[Rt@ODFEPG6?�I�\�IFN®]v@O?-@ONHI � I�G6N^ZKV[I�Za@ONPI�W-B�?hZKGgV[EPJKB�NPZa@�EP?�ACIbV[EHGOVKI@yº,È�m n B�EH?�\�E7EPN�]v@O?-@ONPI�jEPIF?�I�JLZKVKG6DFDv@YZ[G�fdz�IbV�º,Éq§ ¨ ºK�§ ¥ º,È~NH@�JLZKV[G6DbDv@YZ[BVa@�JKE�ZKV[G/jO@�EP?]FGOVKVKEHJLW8G6?�\�IF?�Dv@g\�IbNHNp��IFJLZKVKIFRTEPZ=`@y\�E®\V[@OEH?®Ö-@ONHN"�¸@OB�RTIb?hZa@YVKI�\�E ºK�§kJKE®JLW7G6J�Za@yjcI_V[JKG�JKEH?�EPJLZKVa@mRt@~\�E¯B�?-@ n B-@O?cZ[EPZY`@~W-EP]F]FG6NH@~V[IFNM@YZKEPjY@ORTIF?cZ[I1@ONHNH@~NHB�?�U6r�IbDFDv@�\�IFN¯]v@O?-@ONPIOm�@ONHRTIF?�GiW7IbVQEjY@ONHGOV[E'\�E�ºK�§i?�GOV[RT@ONHRTIF?cZ[IuBZ[EHNPEHDFDv@YZKEpfÄD�B�EP?�\�E�JKEqr-@tB�?1ZKVa@YZKZKGt\�Eq]v@O?-@ONPI�\�EqNHB�?�U6r�IbDFDv@W�@YV[E n B-@OJKE5@ONPNM@k\�EPJLZa@O?�Dv@oZKV[@o\Va@OEH?�ItJKG6BV[]bIl@OE�]v@YW-E�\�IFN n B-@ONPIOm�B�?-@ojcG6NPZa@oJKBW8IbVa@YZa@1NH@ºK�§oW7IbV¯]FB�E3º,Éq§ ¨ º,s§LÚ¿º,Èsm-IFJLEHJLZ[IXB�?-@gZ[IF?�JKEPG6?�IXW�@YV[E @tº,Éq§ ¨ º"Èsm�JKG6JLZa@O?�DFEH@ONHRTIb?hZ[IEH?�\�E^W7IF?�\�Ib?hZ[IQ\-@kB�N^Z[IbV[EPGOV[EdjO@YV[EH@ODFEHG6?�E{\�E5º,s§¡fQ�q@o]FGOVLV[IF?cZ[IT]ar�ItNHG1@YZLZKVa@vjcIbV[J[@�`I n B�EH?�\�E@O?�]ar®��IFJLJ[@uW�V[IFJLJKG)]arswI¯EP?�\�EPW8IF?�\�IF?cZ[I¯\-@uºK�§TI�V[@OU6U6EHB�?�U6I�NM@�\�EP¶8B�JKEHG6?�I�\�E�\Va@OEH?e@YZKZKVa@vjcIbV[JLGNM@�DbG6?-@�JLZKV[G6DFDF@YZa@f ¬ B�N)W-EH@O?�G�\�IFNHNPI5]v@YVa@YZKZ[I_V[EHJLZKEH]ar�I�\�EB�JK]bEPZa@ n B�IFJLZ[G�]FGOVLV[EHJLW8G6?�\�I�@O\y@/jcIbVKI]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�W�V[IbJKJKG)]arswI�GOV[EHDbDFG6?hZ[@ONHE3@ON'\�E3JKGOW�Va@t\�IFN3jY@ONHGOVKI�\�EdºK�§�W8IbV�]FB�E�@vj)j)EHIF?�I�NPGJLZKVKG6DFDv@ORTIF?cZ[G�fÛD�B�IFJLZa@�DFG6?-@�\�IFNPNHI�]v@YV[@YZKZ[IbV[EPJLZ[EP]}r�I�jEHIb?�I�\�Ib�-?�EPZ[@i�LDbG6?-@�\�E8J[@YZ[BV[@ODFEHG6?�IF��ÖJKE7?�GOZKE7]ar�I�N"��B�JKG�\�IFN8ZKIbV[RTEP?�I%�LJ[@YZ[BVa@ODFEPG6?�IF�yEH? n B�IbJLZ[G�]v@OJKGy?�G6?lr-@�?hB�NHNH@g@�]ar�I�A;@YV[I�]FG6?n B�IbNHNHGy]ar�I�JKE7r-@y?�IFN®]v@OJKGy\�IFN7ZKV[@O?�JKEHJLZKGOV[I���� � f�'@�J[@YZKBVa@ODFEHG6?�I�?�IFN8]v@OJKG�\�IFN¡��� � EH?�\�EP]v@B�?-@�]bG6?�\�EHDFEPG6?�I~\�E�ACB�?�DFEHG6?-@OReIF?hZKG|EH?<]FB�E�Z[BZKZ[ISI~\�B�IiNHISU6EHB�?�DbEHG6?�E�JKG6?�IiW8G6NM@YV[EPDFDv@YZ[I\�EPVKIbZKZa@ORTIb?hZ[IlIoNM@i]FGOVKV[IF?cZ[I1\�E���@OJKIo?�G6?�r-@ n B-@OJLE�W-EK`B�@ONP]FB�?-@�EH?�-B�Ib?�Dv@xJKB n B�IFNPNM@~\�E]FG6NPNHIbZKZKGOV[IOÖ?�IFN8]v@OJKGy\�IFN8ZKV[@O?�JKEHJLZKGOV[IQ�Æ ¬ NM@�J[@YZ[BV[@ODFEHG6?�I�]FGOVKVKEHJLW8G6?�\�Iu@ONPNM@�]FG6?�\�EPDFEHG6?�I�\�EACB�?�DFEPG6?-@ORTIF?cZ[Gt@YZKZ[E^jcGg]ar�Iu]FG6?�JKIF?cZ[I�\�E¡GOZKZ[Ib?�IbV[IXB�?®��@OReW-NHE^�-]v@ODFEPG6?�IOf¼�IF\�EM@ORTG�GOVa@yB�?-@gVa@YW�W�V[IbJKIF?cZa@ODFEHG6?�IXUOVa@Y�-]v@e\�E n B-@O?cZ[Gk`IuJLZ[@YZ[Gg�-? n B�E¡\�IF]bV[E^ZKZ[G�f

¾�NHN"�¸@OB�RTIb?hZa@YVKIk\�E�º,s§¡m�NH@�\�EHJLZa@O?�DF@�Ü ¤ JKE¯V[EP\�B�]FIOm�@O?�]ar�IiJKI1\�E�W7G)]bG�m�I n B�IFJLZ[G�A;@YZKZKG\q`@xNHB�G6U6G�@ONPNp��EP?�]FNHEP?-@ODFEHG6?�Ik\�IFNHNPI1]v@YVa@YZKZ[I_V[EHJLZKEH]ar�I1\�E�B�JK]FE^Za@f Ø�@YZ[Gx]ar�I1Za@ONHIoVKEH\�B�DFEPG6?�I�`IW-EHBZLZ[G6JLZ[GXW-EP]F]FG6NH@�I�]}r�I�NH@uZ[IF?�JLEHG6?�I�ºÞÝq`I�W�Va@YZ[EH]F@ORTIF?cZ[I�]FG6JLZ[@O?hZ[IYmNM@X]bGOVKV[IF?cZ[I�À��§%JKE�W-Bq`G]FG6?�JKEP\�IbVa@YV[IYm�@ONHReIF?�GSEH?�W�V[EHRt@S@YW�W�V[G6JLJKEHRt@ODbEHG6?�IOm{EH?�\�E^W7IF?�\�IF?cZ[Io\-@iºK�§Ó?�IFNPNM@SDFG6?-@�\�EJ[@YZ[BV[@ODFEHG6?�IOf

��?o]FG6?�\�EPDFEHG6?�E¡\�E¡J[@YZ[BV[@ODFEHG6?�IuNM@g]bGOVKV[IF?cZ[Ie`Iu\-@YZa@y\-@

À ¥ Ê �Öß àá� �pºKÉ'§ ¨ º,È �   -\�G/jcIâÊTV[@YW�W�V[IFJKIF?cZa@TB�?%W�@YVa@ORTIbZKVKGg\�E¡W�V[G)]bIFJKJKG�m ß `IuNH@gNM@YVKU6r�IFDFDv@�EH?k\�E^V[IFDFEPG6?�IuW8IbVKW7Ib?)�\�EH]bG6NM@YV[Iu@ON¡\�EHJKIFU6?�GeI à `IuNH@gNHB�?�U6r�IbDFDv@T\�IFN ]v@O?-@ONHIYm�]bEHG�`I�NM@g\�EPJLZa@O?�Dv@�ZKVa@g\V[@OEH?oIuJKG6BV[]FIOf��N'W�@YVa@OReIbZKV[Gt\�EqW�VKG)]FIFJLJKG9Êkr-@tNPI�\�EHRTIb?�JKEHG6?�E3\�E'B�?-@%]bGOVKV[IF?cZ[I�\�EPj)EHJ[@eW8IbV�B�?-@tZ[IF?�JKEPG6?�I@ON n B-@O\Va@YZKGgI�W-Bq`GTIFJKJKI_V[IXIFJ�W�V[IFJKJKGt]bG6RTIÊ ¥1ã£ä³åçæ�èÔ -\�G/jcI åÅæ�è `IsNM@�]v@YW�@O]FE^ZY`@�\�IFNPNp��G6JLJKEH\�G�W8IbV�B�?�EPZ=`@�\�E�JKBW7I_VK�-]FEHIu� åçæ�è ¥êé ­�Ë æ�è � mO]bG6? é W�@YV[E)@ONHNH@]FG6JLZ[@O?hZ[I�\�EHIbNHIbZKZLV[EH]v@�\�IFNHN"��G6JKJLEH\�GeIQË æ�è W�@YV[E @ONHNPGgJ�W7IFJKJLGOV[IX\�IFNPNp��G6JKJKEH\�G � I ã£ä `I�NM@�RTGO�-EHNPEPZY`@\�IFEqW8GOVKZa@YZ[GOVKE'EP?hZ[I_V[IFJKJ[@YZKE�@ONHNH@T]FG6?�\�B�DFEHG6?�I�ZKV[@TJKG6BV[]FI�I�\Va@OEP?®m7EH? n B�IFJLZ[Gt]v@OJLG%IbNHIbZKZLV[G6?�Epf

öc¹

Page 14: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

� @ONPI�IFJ�W�V[IFJKJKEPG6?�I�`I�jY@ONHEP\-@�?�G6?eJKG6NHG�W7IbV5ºK�§ ¥ º,Éq§ ¨ º,È�mhRt@�@O?�]}r�I�W7IbV�jO@ONPGOV[E�JKBW7I_V[EHGOV[E\�E®º,s§¡mJKI�A;@O]F]bEM@ORTG�N"��EPW8GOZ[IFJKE�\�E8]bGOVKV[IF?cZ[I�EH?tDFG6?-@�\�E�J[@YZ[BVa@ODFEPG6?�I�EH?�\�E^W7IF?�\�IF?cZ[I�\-@�ºK�§ fz�G6EH]arswI~@ONHNp��IF?cZKVa@YZa@�EH? JK@YZ[BVa@ODFEPG6?�IxºK�§ ¥ ºKÉ'§ ¨ º,È�m�W7G6JKJKEH@ORTG�V[EH]v@vjY@YV[I~A;@O]FEPNHRTIb?hZ[INp��IFJLW�V[IbJKJKEHG6?�I�\�IFNHNH@u]FBVLjO@X]ar�I�JKIbW�@YVa@XJLB�N-W-EH@O?�GX\�IFNPNHI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I¯\�E-B�JK]bEPZa@mhNM@�V[IFU6EPG6?�I]FG6JKEP\�\�IbZKZa@k��ZKV[EPG)\�G6�g�:W7I_V5º,s§TRTEP?�GOV[I�\�E n B�IFNPNM@�\�E�JK@YZ[BVa@ODFEPG6?�I � I n B�IbNHNM@�\�E�J[@YZ[BV[@ODFEHG6?�IO¢JKE®ZKVa@YZLZa@�\�E¡B�?-@gW�@YV[@Y�7G6NM@�\�IFJK]bVKEPZKZa@�\-@ONHN"��I n B-@ODFEHG6?�I

À ¥ Êë� ß à �Sº  s§ «� IX]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�E¡B�JK]FEPZ[@e]FG6J�` ·¡GOZKZ[Ib?�BZ[IuJKG6?�GgV[@YW�W�V[IFJKIF?cZa@YZ[IX?�IFNHNH@��-U6BVa@eJLIFU6B�IF?cZ[IOf

¬ IOm3?�IbNHNp��IFJLW�V[IbJKJKEHG6?�It\�IbNHNM@l]FGOVKV[IF?cZ[ITEP?�J[@YZ[BV[@ODFEHG6?�IOm'jcG6U6NHEM@OReGlEP?�]FNHB�\�IbVKIQ@O?�]}r�IeNp��I_¶7IbZKZKG\�E�@O]F]FGOVK]FEM@ORTIb?hZ[G�\�IFN�]F@O?-@ONHI�@ONHN"�¸@OB�RTIF?cZa@YV[Ik\�IFNHNH@�º,s§ m�]ar�I�\q`@�NPB�G6U6G�@�B�?-@�NHIFU6U6IbV[@EH?�]bNHEH?-@ODbEHG6?�I�jcI_V[JKGXN"�¸@ON^Z[Gu\�IbNHNHI�]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�E�B�JL]FEPZa@mcW7G6JLJKEM@ORTGuB�J[@YV[I�Np��IbJLW�V[IFJKJLEHG6?�I¯\�EZ[E^W7GeACIb?�G6RTIF?�G6NHG6U6EP]FG

À ¥ Êë� ß à ���pºKÉ'§ ¨ º,È �   ��´³*Gì8º,s§ � -\�G/jcI5EHN�W�@YV[@ORTIbZKV[GSì�Va@YW�W�V[IFJLIF?hZ[@�N"��EH?cjcIbV[JLG�\�E�B�?-@�Z[IF?�JKEPG6?�IOmc]}r�I5j)EHIF?�I�\�E)JKG6NHE^Z[G�]ar�EM@ORt@YZa@Z[IF?�JLEHG6?�I�\�E�·�@YV[N�Ycm=EP?y@O?-@ONHG6U6EM@�@ n B-@O?cZ[G�@O]F]F@O\�I5?�IFE)��� � mY@O?�]ar�I5JKI�EP? n B�IFJ�Z[G�]v@OJKG�EPN�ACIb?�GY�RTIF?�G��-JKEH]bGT]ar�IXW7GOVKZ[@T@ONHN"��EH?�]bNHEH?-@ODbEHG6?�I�\�IFNHNPIX]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�Iu\�E B�JL]FEPZa@o`Iu]FG6ReW-NPIbZa@ORTIF?cZ[I\�EPjcI_V[JKGe\-@ n B�IFNPNHG�\�IFNHNH@�V[EP\�B�DFEHG6?�Iu\�IFNHNH@gNHB�?�U6r�IbDFDv@TIbÙe]v@O]FIX\�E®��@OJKIu\�IFE'��� � f

¬ B�NPNM@l��@OJKIe\�IFNHNPITIFJLW�V[IbJKJKEHG6?�E{�-?�GOVa@o\�IbV[E^jO@YZKI1`IT@O?�]ar�ITW7G6JLJKEP�-EPNHIgZLVa@O]F]FEH@YV[IeNH@lZKVa@O?�J��]v@YVa@YZLZ[IbV[EPJLZ[EH]F@QEP?�UOV[IFJKJLGY�ÕB�JK]FE^Za@%W8IbV�B�?iZKV[@O?�JKEHJLZKGOV[Ií�Æ ¬ ¢¡JKE3ZKVa@YZLZa@T\�E�B�?-@%W�@YVa@Y�8G6NM@t]ar�IEH?�EPDFEM@SW7IbVtºKÉ'§ ¥ º,Èsf�Ø�E�JKG6NPEPZ[G�JKE�ZKVa@OJK]bBVa@~NM@�\�EPW8IF?�\�IF?�Dv@x\�IFNPNM@�ZLVa@O?�JK]v@YVa@YZLZ[IbV[EPJLZ[EH]F@\-@ONHNH@Tº,s§oI�JKE ZLVa@O]F]FEH@�B�?®��B�?�EH]v@e]bBVKjO@m�EH?�\�E^W7IF?�\�Ib?hZ[IbRTIF?cZ[I�\-@ON®jO@ONPGOV[I�\�Eqº,s§¡f

z�IbVTE�ZKV[@O?�JKEHJLZKGOV[Eç�Æ ¬ IFJKEPJLZ[G6?�G~jcIbVKJKEHG6?�E�]FG6ReW-NHIbRTIF?cZa@YV[E�@�]v@O?-@ONPI�Í m5?�IFNPNHI n B-@ONHEEHN�JKB�-J�ZKVa@YZ[GÓ`Ik\�E5Z[EPW8G~οIlNPIl\�E^¶7B�JKEPG6?�E�\�E�JKG6BV[]bIkIk\�E�\Va@OEP?ÓJKG6?�G~\�E�ZKEPW7GQÍ f���?ÓZ[@ONHEZKVa@O?�JLEHJLZ[GOVKE'EPN'ZKVa@OJ�W7GOVKZ[GgZKVa@TJKG6BV[]bI�I�\Va@OEH?x`IXGOZKZ[IF?hBZ[GTZKVa@OReEPZ[IuB�?-@T]FGOVKV[IF?cZ[I�\�E'NM@O]FB�?�IOm]ar�I�jcIb?�U6G6?�GuEP?�\�GOZKZ[I�@ONHNH@�JLBW7IbVK�-]bEHI�ZLVa@ORTEPZKI�Np��@YW�W-NHEH]F@ODFEHG6?�I�\�E�B�?-@�ZKIF?�JKEHG6?�I�?�IFUc@YZKEPjY@�ZKV[@Uc@YZ[IuIX�-B�NPÑ8f5z�IbVKZa@O?cZ[GTNPI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�IX\�E'B�?oZKVa@O?�JKEPJLZ[GOV[IX@e]v@O?-@ONPI�ÍSJKG6?�GtI n B�EPjY@ONHIF?cZ[E@ n B�IFNPNHIt\�E�B�?xZKV[@O?�JKEHJLZKGOV[I%@o]v@O?-@ONHIQÎ�m3W-BV[]arswI%JKE�JK]v@OR��-EP?�G�EsJKIFU6?�E�\�E�]bGOVKV[IF?cZ[E5ITZ[IF?)�JKEPG6?�Epf��ç�U ¬ @g]v@O?-@ONHI�Í1r-@O?�?�GTW�V[IFJLZa@ODbEHG6?�EqEP?�ACIbV[EPGOV[Epm�@gW�@YV[E^ZY`@g\�Eq@ONPZKV[Iu]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�IOmV[EPJLW7IbZLZ[G�@OE�]FGOVKV[EPJLW7G6?�\�IF?cZ[EZKV[@O?�JKEHJLZKGOV[E-@�]v@O?-@ONHI�Î�mcEH?�]FG6?�JKIFU6B�Ib?�Dv@u\�IFNPNM@�V[EH\�GOZLZa@�RTGO�-EHNPEPZY`@\�IFNPNHIXNH@O]FB�?�IXV[EPJLW7I_ZKZ[GT@OU6NPE¡IFNHIbZLZKV[G6?�Epf ¬ E¡W-Bq`Gt]bG6ReW7IF?�JK@YV[IuW8IbVa@ONPZLV[GgZa@ONPIuV[EP\�GOZKZa@�RTGO�-EHNPEPZY`@

ö6ö

Page 15: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

]FG6?xB�?�@OB�RTIb?hZ[Gk\�IFNHNH@oNM@YV[U6r�IFDbDv@o\�E�]F@O?-@ONHI ß m3]FG6J[@o]ar�ITJKE�A;@oRTG6NPZKGlAMV[I n B�IF?cZ[IFRTIb?hZ[IYm\-@YZ[Gl]}r�IgNM@%\�EHJLW8G6?�EP�-EHNPEPZY`@%\�E�ZKVa@O?�JKEPJLZ[GOV[EÁ�U ¬ ]FG6ReW-NHIbRTIF?cZa@YV[E5`Ig@ONHNM@Q��@OJKIe\�IbNHNM@QZ[IF]F?�GY�NHG6U6EH@ ½ �U ¬ m�]ar�IkVa@YW�W�V[IFJLIF?hZ[@m5]FG6RTIQjcIF\V[IFRTG�W-EK`B�@vjY@O?hZ[E"m�B�?�G�\�IFE�RTGOZ[GOVKE�ZKVa@OEH?-@O?cZ[E\�IFNPNp�¸@YZLZ[B-@ONHI�EH?�\�B�J�ZKV[EM@gRTEH]bVKG)IFNPIbZKZKV[G6?�EP]v@f

�®ZKV[@O?�JKEHJLZKGOV[E7�U ¬ �-?�GOVa@�jEPJLZ[EcJKG6?�G¯\�EcZ[E^W7G�@O\�@YVKV[EP]F]ar�EHRTIF?cZ[G��"G¯IF?�r-@O?�]bIFRTIF?cZ � mYW8G6E^�]ar�wI5W7IbV�Z[Ib?�JKEHG6?�I5\�EUc@YZKI�?�B�NPNM@�EHNh]v@O?-@ONPI5?�G6?�IbJKEHJLZKI5I5NM@�JKB-@�ACGOV[Rt@ODbEHG6?�I�`I�B�?-@�]FG6?�JKIbU6B�IF?)�Dv@t\�IFNPNp�¸@YVLV[EH]F]ar�EPRTIF?cZ[GQ\�E3W7GOVKZa@YZKGOV[Eq\�IFN3ZKEPW7GtGOW�W8GOVKZ[B�?�G%GOW7IbV[@YZ[GtZKVa@ORTE^Z[I�Np��@YW�W-NHEP]v@ODFEHG6?�I\�E®B�?-@�Z[IF?�JKEPG6?�I�\�E8Uc@YZ[IOf{·sJKEPJLZ[G6?�G�@O?�]ar�I�ZKV[@O?�JKEHJLZKGOV[E7\�E8Z[E^W7Gy\�EPjcI_V[JKG�m�?�IFE n B-@ONHE8EPN7]v@O?-@ONPI`IlW�VKIFIFJKEPJLZ[IF?cZ[IOm�GOZKZ[Ib?�BZ[G�ZKVa@ORTE^Z[IQEHReW-EH@O?hZ[@ODFEHG6?�I%\�E�\V[G6Uc@O?hZKE�?�IFNPNHGiJLZKVa@YZ[GiJKBW7I_VK�-]FEM@ONPII�NHGkJLEdW-Bq`GkA;@YV�JK]FG6RgW�@YV[EPV[Iy]FG6?~Np�¸@YW�W-NPEH]v@ODbEHG6?�I�\�E{B�?®��GOW�W7GOVKZKB�?-@lZ[IF?�JKEPG6?�Ie\�EdUc@YZ[IOf � @=�NHE�ZKVa@O?�JKEPJLZ[GOV[E¯JKE�\�Ib�-?�EPJK]FG6?�G�@�J�jB�GOZa@ORTIb?hZ[G<�:G�\�I_W-NHIbZ[EPG6? � fÿ��IFN�]F@OJKG�\�IFN¯ZKVa@O?�JLEHJLZ[GOVKI\�IbW-NPIbZ[EHG6?S@T]F@O?-@ONHI�ÎxNH@gZ[IF?�JKEPG6?�I�\�EqJKG6U6NPEM@tº"È�V[EPJKB�NPZ[@ n B�EP?�\�Eq?�IFUc@YZ[E^jO@TIXNM@gZKV[@O?�JK]v@YVa@YZL�Z[IbVKEHJLZ[EP]v@tEH?�UOV[IbJKJKGY�ÕB�JL]FEPZa@TV[EPJKB�NPZ[@tZLVa@OJKNM@YZ[@t@ONHNp��EH?�\�EPIbZKV[GTV[EPJLW7I_ZKZ[GQ@ n B�IFNPNM@T\�IFNPNp��I n B�E^jO@ONPIF?hZKIIF?�r-@O?�]FIbRTIF?cZv¢

� Ii]v@YV[@YZKZ[IbV[EPJLZ[EP]}r�Ii\�E�B�JK]FE^Za@ÓJKG6?�G�W�Va@YZ[EH]F@ORTIF?cZ[ISI n B�E^jO@ONPIF?hZKEu@ n B�IbNHNHI�\�IFN�ZKVa@O?�JLEHJLZ[GOVKIIF?�r-@O?�]FIbRTIF?cZvmO]FG6?�N"��B�?�EP]v@�jY@YV[EM@O?cZ[I�\�IFEhjY@ONHGOVKE6\�EcZKIF?�JKEHG6?�I5ºKÉ'§�]bGOVKV[EHJ�W7G6?�\�IF?cZ[E�@¯]FEM@OJL]FB�?-@\�E®Za@ONHE®]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�IOm-]}r�IuV[EHJKB�N^Za@O?�GgZLVa@OJKNM@YZKE7jcIbV[JKGgEHN®��@OJKJKG�fî�G+jcIFJL]FEM@O?�\�G%EqJKIbU6?�E�\�Eq]FGOVKVKIF?hZKE3I�Z[IF?�JKEPG6?�EqW7G6JLJKG6?�GQA;@O]FEHNPRTIF?cZ[I�GOZKZ[IF?�I_V[JKE3NPI�]v@YVa@YZL�Z[IbVKEHJLZ[EP]ar�IX\�IFE®ZKVa@O?�JLEHJLZ[GOVKE'@�]v@O?-@ONHI5Í m-JKEM@�IF?�r-@O?�]FIFReIF?hZ�JKEM@�\�IbW-NHIbZKEHG6?®f

öï/

Page 16: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

·sJLEHJLZ[G6?�G�\�EPjcIbVKJKEcJKEHR��7G6NPEO]FE^V[]FB�EPZ[@ONHEOW7I_VqEOZKV[@O?�JKEHJLZKGOV[E0�Æ ¬ f�D�B�IbNHNHE6W-EK`B�]FG6RyB�?�IFRTIF?cZ[I{B�J[@YZ[E?�G6?�\-@O?�?�GSEH?�ACGOV[Rt@ODbEHG6?�E{JKB�N�Z[E^W7G��p@O\�@YVLV[EH]F]ar�EPRTIF?cZ[G1GS@oJLjB�GOZ[@ORTIF?cZ[G � mqRT@kEH?�\�EP]v@O?�GJKG6N^Za@O?hZKGeJKI�EHN¡]v@O?-@ONPIe`I5Í1GeÎ�¢

¬ E8BZKEHNHEPDFDv@XZa@ON^jcG6NPZa@u@O?�]ar�I�B�?%JLEHR��7G6NPG�@O?�]FGOV�W-EK`BtU6IF?�IbVa@ONPIOm)jY@ONHEH\�G�JLEM@XW7I_Vð�U ¬ @�]v@O?-@ONPIÎ~JLEM@�W8IbVÍ�U ¬ @g]F@O?-@ONHI5Í ¢

·sJLEHJLZ[G6?�GQEP?�-?�Ig\�IFEqJKEHR��7G6NPEpm7ReG6NPZ[GeW8G)]FGQB�J[@YZKEpm®]ar�Iy\�EHJLZ[EP?�U6B�G6?�G%ZLVa@±�Æ ¬ @O\~@YVKVKEH]F]ar�E^�RTIF?cZ[Go�p@�JLEH?�EHJ�ZKVa@ � IÞ�U ¬ @gJLj)B�GOZa@ORTIF?cZ[Gk�p@g\�IFJ�ZKVa@ � ¢

¶8�M÷�ÃF9s,/(+*�&3üv2:üb,/.�(+$oË#ñ�ú�Ì��N8ZKVa@O?�JLEHJLZ[GOVKI��0ò�· � �"�cB�?�]_Z[EHG6?óò�EHIFNP\Q·�¶7Ib]bZ � Va@O?�JKEPJLZ[GOV � `I�EPN�W�V[EPRTG�ZKVa@O?�JLEHJLZ[GOVKI�@�Ib¶7IbZLZ[G\�E�]v@ORgW7Gx]ar�I1ACB<VKIv@ONHEPDFDv@YZ[GxI1]FG6?cZ[EPIF?�IOm¯]bG6RTI�`I1]ar�EM@YV[G�\-@ON�?�G6RTIOm�B�?-@�U6EPB�?�DFEHG6?�IeÍ��Î�f�z�VKIF?�\�EM@ORTG�\-@YW�W�V[EPRt@�EH?Ð]bG6?�JKEH\�IbV[@ODFEHG6?�IiEHN¯ZKV[@O?�JKEHJLZKGOV[I~�7ò�· � @�]v@O?-@ONPIiÎ�m�EHN�]FB�EACB�?�DFEPG6?-@ORTIF?cZ[GlW-Bq`G%IFJKJKI_V[Ie]FG6RgW�V[IFJKG%EH?S��@OJKIg@ONHNHGQJK]ar�IFRT@%\�E3W�V[EP?�]FEPW-EPGlV[E^W7GOVKZ[@YZ[GQ?�IFNHNH@�-U6BVa@eJLIFU6B�IF?cZ[IOf

ö0F

Page 17: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

�'@�]FGOVLV[IF?cZ[I~JK]bGOVKV[ISZKVa@xNp��IFNHIbZLZKV[G)\�G�\�E�JKG6BV[]bIiI n B�IFNPNHG�\�E�\Va@OEP? @YZKZKV[@/jcIbVKJKG�B�?<W7IFDbDFG\�E�JKIFRTEP]FG6?�\�BZKZ[GOVKIi\V[G6Uc@YZKG�Î�m�?�IFN n B-@ONHI�JKG6?�G�V[IF@ONHEHDbDv@YZ[I�\�B�I~\�EP¶8B�JKEHG6?�E�\�E�Z[E^W7G1Í × m]ar�Io]FG6JLZKEPZ[B�EPJK]FG6?�GxNp��IFNHI_ZKZKV[G�\�G~\�E�Uc@YZ[IOf|·�JKJKIF?�\�GxNPIo\�EP¶8B�JKEHG6?�E�\�E�Uc@YZKIlW-EK`B�\VKG6Uc@YZ[IOm�NH@DFG6?-@�\�E�JLjB�GOZ[@ORTIF?cZ[GxJKE�IFJLZKIF?�\�I�W�VKIbjO@ONPIF?cZ[IFRTIF?cZ[I�?�IFNHNH@�V[IFU6EHG6?�ISÎ�f ¬ I�JLBW�W7G6?�EM@OReG\�E5@YW�W-NPEH]v@YV[ItB�?-@oZ[Ib?�JKEHG6?�ItRTG6N^Z[GkW-EP]F]FG6NM@oZKV[@o\Va@OEH?�ItJKG6BV[]bItItB�?-@1ZKIF?�JKEHG6?�IQ?�IFUc@YZKEPjY@ºKÉ'§lZKVa@yUc@YZ[I�I�JKG6BV[]FIYm�EP?lReG)\�G�\-@�W8G6NM@YV[EPDFDv@YV[I�EP?hjcI_V[J[@ORTIF?cZ[I�NM@�U6EHB�?�DbEHG6?�IOm-NM@�]FGOVLV[IF?cZ[IJK]FGOVLV[IbVY`@TEP?1B�?�]F@O?-@ONHI�]FG6?1\�EPRTIF?�JKEPG6?�IXjcIbVKZKEH]v@ONPIXjO@YVKEM@Y�-EHNPI�@ON¡jO@YVKEM@YV[I�\�E3ºKÉ'§ m�]FG6ReW�V[IFJLGZKVa@�E��7GOV[\�E�\�IFNHNPI�\�B�I�DbG6?�I�\�E7JLjB�GOZ[@ORTIF?cZ[G�\�G+j)BZ[I�@ONHNPI�\�EP¶8B�JKEHG6?�EhÍ8×5fdz�IbV5W-EP]F]FG6NPE�jY@ONHGOV[E\�IFNPNM@�Z[IF?�JKEPG6?�I�ºK�§k@YW�W-NHEP]v@YZa@�ZKVa@�\V[@OEH?QI�JKG6BV[]FIYm�EHN®�7ò�· � JKE8]bG6ReW7GOVKZ[@ n B�EH?�\�E8EH?QRTG)\�GJKEPRTEHNPIt@ n B-@O?hZKG�U6EÇ`@ojEHJ�Z[G1W7IbV�EHN³�Æ ¬ m�]FG6RTItB�?-@1V[IFJLEHJLZ[Ib?�Dv@iEPN�]FB�E�jY@ONHGOV[ITW-Bq`G�IFJKJKI_V[IjY@YV[EM@YZ[GtW8IbV�RTIFDFDFG%\�IFNPNM@lºKÉ'§ ¢�EP? n B�IFJLZ[G%]v@OJKG%Za@O?hZKGQW-EK`B~UOVa@O?�\�I%`IyEH?�RTG)\�B�NPGtEHN3jY@ONHGOV[I\�IFNPNM@1º,Éq§~Za@O?cZ[GoRt@OU6U6EPGOV[I�V[EHJLB�NPZa@%EHN�jO@ONPGOV[I�\�E{V[IbJKEHJLZKIF?�Dv@kW�V[IFJLIF?hZKIeZKVa@k\V[@OEH?�IgJKG6BV[]FIOf� BZKZKGk]FEÇ`GlW-Bq`GoIFJLJKIbV[I�Va@YW�W�V[IFJKIb?hZa@YZKGoZKVa@ORTE^Z[I�NHIg]v@YVa@YZKZ[I_V[EHJLZKEH]ar�Ig\�E{B�JK]FE^Za@l?�IbNHNM@QV[IFU6EPG6?�IW7I_VTº,s§�W-EH]F]FG6NH@md]}r�IQJKG6?�G�JKG6JLZ[@O?�DFEM@ONPRTIF?cZ[It\�IFNHNPITV[IbZKZKIt]}r�I%]FG6?�-B�EPJK]FG6?�G�?�IFNHN"��GOV[EPU6EH?�IOm]FG6RTItEPNHNPB�JLZKVa@YZ[G1?�IbNHNM@o�-U6BVa@SJKIFU6B�Ib?hZ[IYfi�'@SW8IF?�\�IF?�Dv@�\�IFNHNH@1]v@YVa@YZKZ[I_V[EHJLZKEH]v@o]FGOVLV[EHJLW8G6?�\�I@ONHN"��EP?hjcIbVKJKGe\�IFNPNM@yV[IFJKEPJLZ[IF?�Dv@gIu\�EPRTEH?hB�EHJK]bI�@ONHN"�¸@OB�RTIb?hZa@YVKI�EP?kRTG�\�B�NHG�\�IFNHNH@Tº,Éq§¡f

z�IbV�º,Éq§S@Y����@OJLZa@O?�DF@T?�IFUc@YZ[EPjY@eNPIX\�B�I�DFG6?�I�\�E JLj)B�GOZa@ORTIF?cZ[GTJKE ]FG6?�U6EPB�?�U6G6?�GtIXEHN ]v@O?-@ONPIJK]FG6RgW�@YV[IOm�W7IbV¯]FB�E NM@g]bGOVKV[IF?cZ[IXJLEq@O?�?hB�NHNH@¢�EPN¡jY@ONHGOVKIu\�EqºKÉ'§kW7IbV¯EHN n B-@ONPI n B�IFJLZ[Gt@vj)j)EHIF?�IJKE�\�Ib�-?�EHJK]bI�Z[Ib?�JKEHG6?�I1\�E�W-EH?�]ar)�ÕGO¶ IoJLE�EH?�\�EP]v@�]FG6?¿ºKô5f z�IbVtZKIF?�JKEHG6?�E�ºKÉ'§<EP?<ReG)\�B�NHGRt@OU6U6EPGOV[E7\�E'ºKô|EPN7ZKVa@O?�JKEPJLZ[GOV[IX�0ò�· � JKE¡]FG6ReW8GOVKZa@y]FG6RTI�B�?oEH?cZ[IbVLV[BZKZ[GOV[IX@YW7IbVLZ[G�fD�B-@O?�\�GeJKE¡@YW�W-NPEH]v@�EP?hjcIF]bIuB�?-@gºK�§k?�G6?%ZLVa@OJK]FBVa@Y�-EPNHIg�"JKBW8IbV[EPGOV[I�@ n B-@ONH]ar�I�\�IF]FEHReG\�E3jcG6NPZ � m®EHN�]FG6RgW7GOVKZa@OReIF?hZKGt\�IFNd\�EHJLW8G6JKEPZ[E^jcGQ?�G6?iW-Bq`GlW-EK`B~IFJLJKIbV[Ig@OJKJKEPRTEHNH@YZ[G%@ n B�IFNHNPG%\�EB�?-@XV[IFJLEHJLZ[Ib?�Dv@�NHEP?�Iv@YV[IO¢3W8IbV5B�?-@�º,s§QJKEHU6?�E^�-]v@YZ[EPjY@mhNM@X\�E^¶7IbV[Ib?�Dv@�\�E�W8GOZ[IF?�DFEH@ONHI�ZKVa@X\Va@OEP?I%]v@O?-@ONHI%V[EHJKB�N^Za@iRT@OU6U6EHGOV[ItEP?ÓRTG�\�B�NHG�\�E n B�IFNHNH@SZKV[@iJKG6BV[]bIkIk]F@O?-@ONHIOm{W7IbVe]FB�E�NPIlDbG6?�I\�E�JLjB�GOZa@OReIF?hZKG~]ar�Io\�Ib�-?�EPJK]FG6?�G�EHN�]v@O?-@ONPIoJLZ[IFJLJKG�@OJKJKB�RTG6?�GiB�?-@�ACGOV[Rt@i@OJKEHRTReIbZKV[EP]v@mV[EPJKB�NPZa@O?�\�G�W-EK`B1@ORgW-EHI�EH?l]FGOVKV[EPJLW7G6?�\�IF?�DF@T\�IFNHNH@�V[IFU6EPG6?�IX\�E¡\Va@OEP?®f¾�N3]bVKIFJK]FIbVKIg\�E{º,s§¡m®EHN3]v@O?-@ONPIy\�EPjEPIF?�I�JKIFRgW�V[I�W-E[`B�JLZKV[IbZLZ[Gt�-?�Gk@tV[EHJLB�NPZa@YV[I�J�ZKV[G6DFDv@YZKG%EP?]FGOVKVKEHJLW8G6?�\�IF?�Dv@l\�IbN�\Va@OEH?®m®]FG6ReI�EH?�\�EP]v@YZ[GQ?�IFNHNH@Q�-U6BV[@QJLIFU6B�IF?cZ[IOfu��? n B�IFJ�Za@%]bG6?�\�EHDFEPG6?�IEHN�]F@O?-@ONHIyJKEdIFJLZ[Ib?�\�Ie\-@ONHN"��IFJ�ZKV[IFRTE^ZY`@T\�EdJKG6BV[]FIy�-?�Go@ON3W-B�?cZ[Gl\�G+jcI�EH?�EPDFEM@QNM@QJLZKV[G6DbDv@YZ[BVa@f¬ E¯r-@iEH?|Za@ON�]v@OJKG�B�?�ACIF?�G6ReIF?�G�\�E¯JK@YZ[BVa@ODFEPG6?�Io\�IFN�ZKBZKZ[Gx@O?-@ONPG6U6G�@ n B�IbNHNHGiU6E�`@ij)EHJLZKGW7I_VTE�ZKVa@O?�JKEPJLZ[GOV[EÅ�U ¬ f ¬ E�r-@ n B�EH?�\�E�B�?�]FG6ReW8GOVKZa@ORTIb?hZ[G�]ar�I1@YW�W�V[G6JKJLEHRt@ n B�IFNHNPG~\�IFNU6IF?�IbV[@YZ[GOV[I5EH\�IF@ONHI�\�E�]FGOVKV[IF?cZ[I�]FG6?cZKV[G6NPNM@YZ[G�EP?�Z[IF?�JKEPG6?�IOf�� I5]v@YVa@YZKZ[I_V[EHJLZKEH]ar�I�]FGOVKVKEHJLW8G6?�\�IF?hZKE@�jO@ONPGOV[EhI n B�EPJLW�@ODFEM@YZKE\�IFNHNH@¯Z[IF?�JKEPG6?�I�ºKÉ'§g?�G6?yJKG6?�G�W7IbVY`G�I n B�EHJLW�@ODbEM@YZ[IO¢'JKE)W-Bq`G�\�EHReG6JLZKVa@YV[I]ar�I�EH?tJ[@YZKBVa@ODFEHG6?�I�NH@X]FGOVKVKIF?hZKI�\�E8\Va@OEP?%À<EP?tB�?Q�0ò�· � r-@�B�?-@�\�E^W7IF?�\�IF?�DF@ n B-@O\Va@YZ[EH]F@\-@ONHNH@�Z[Ib?�JKEHG6?�I�ºKÉ'§¡m-JKIF]bG6?�\�GtNM@yJKIFU6B�IF?cZ[I�I n B-@ODFEHG6?�IY¢

À ¥ À�s§�§ � ´ ¨ ºKÉ'§º,ô �   -

öïX

Page 18: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

\�G/jcIXÀ��§)§�`I�NM@g]bGOVKV[IF?cZ[IX\�E \Va@OEP?k]ar�I�JKE¡r-@�W8IbV�º,Éq§o?hB�NHNH@f � @ONPI�VKIFNM@ODFEPG6?�IuVa@YW�W�VKIFJKIF?cZa@NM@�ZKVa@O?�JK]v@YV[@YZKZ[IbV[EPJLZ[EP]v@~EH?�UOVKIFJKJKGY�ÒB�JK]FEPZ[@�IkW-Bq`GxIFJKJKI_V[IoV[EPW8GOVKZa@YZa@�UOVa@Y�-]v@ORTIb?hZ[IkJKB�N�W-EH@O?�GºKÉ'§��ÒÀ��f

��?�W�VKEHRt@t@YW�W�V[G6JLJKEHRt@ODbEHG6?�I�W7G6JLJKEM@ORTG%@OJKJLB�RTIbV[Iy]ar�IyNM@TZKVa@O?�JK]F@YVa@YZKZ[IbVKEHJLZ[EP]v@tJKEM@tEP?�\�EPW7Ib?)�\�IF?cZ[Io\-@ON�jO@ONPGOV[Ik\�E�º,s§ �"]FG6J[@�]}r�I1A;@YVKIFRTG~EP?ÓZ[BZKZKIkNHIl@YW�W-NHEP]v@ODFEPG6?�E�?hB�RTIbV[EP]ar�I � m5]ar�I]FGOVKVKEHJLW8G6?�\�IX@O\l@OJKJKB�RTI_V[IOm�]FG6RTI�@Y���-EH@ORTG�A;@YZKZ[GyEP?%W�V[Ib]FIF\�IF?�Dv@m�GOV[EPDFDFG6?cZa@ONHE7NPI�]v@YVa@YZKZ[I_V[E^�JLZ[EP]ar�I�\�E8B�JK]bEPZa@XEP?tJ[@YZ[BVa@ODbEHG6?�IOf���?eV[Iv@ON^ZY`@ n B�IFJLZ[I�?�G6?tJLG6?�G�W7IbV[ACI_ZKZa@ORTIF?cZ[I�GOV[EHDFDbG6?hZa@ONPEpm)@]v@OB�J[@�\�IFN A;@YZKZ[G�]}r�IuEHN®W-B�?cZ[GeEP?k]FB�E¡EH?�EPDFEM@�NM@yJLZKV[G6DbDv@YZ[BVa@�JKE¡JLW7G6JLZ[@gNHIbU6U6IbV[RTIF?cZ[I�jcIbV[JKGgEHNJKG6BV[]bI�@ONHNp��@OB�RTIF?cZa@YV[I�\�IFNHNH@XZ[IF?�JKEPG6?�I�ºK�§QW8IbV�]FB�E�NM@XJLZKIFJKJ[@XZ[Ib?�JKEHG6?�I�º,��j)EHIF?�I�@YW�W-NPEH]v@YZ[@@�B�?l]F@O?-@ONHI�\�E®NHB�?�U6r�IFDbDv@�ReEH?�GOV[IOm)\-@O?�\�Gg]FG6JÇ` ·®NHB�G6U6G�@�B�?-@�]FGOVLV[IF?cZ[I�\�E®\Va@OEH?QRt@OU6U6EPGOV[IOf�{�¸@O?�\-@ORTIF?cZ[Gg\�IFNHNPIX]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�E'B�JL]FEPZa@�EH?lDFG6?-@e\�E¡J[@YZ[BVa@ODbEHG6?�Ie`I�W7IbVK]FE�`GgEH?�]FNPEH?-@YZ[G�mEH?tReG)\�G�JKEPRTEHNPI�@ n B-@O?hZ[Gy@O]b]v@O\�I�?�IFE7��� � @�]v@OB�J[@�\�IFNPNp��I_¶7IbZKZKG�·�@YV[N�Ycf��'I�]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I\�E¡B�JK]FE^Za@e\�E¡B�?1�7ò�· � @�]v@O?-@ONHI�Î~r-@O?�?�GeW8IbV[]FEÇ`GTNp��@OJLW7I_ZKZ[G�JKGOZKZ[G�Va@YW�W�V[IFJKIb?hZa@YZKG�f

�'@eU6EHB�?�DFEPG6?�IXZKVa@gUc@YZ[IuIX]v@O?-@ONHIe`IuW7G6NH@YV[EHDbDv@YZa@eEP?hjcIbVKJ[@ORTIF?cZ[IOm n B�EP?�\�E j)EHIF?�IX@YZKZKVa@vjcIbV[J[@YZ[@\-@¯B�?-@¯]bGOVKV[IF?cZ[IsReG6NPZ[G�W-EH]F]bG6NM@�\�EcjY@ONHGOV[I{]FG6ReW�V[IbJKG¯ZKVa@�NHI{\�IF]FEP?�I�\�EhW-EP]FGc@OReW8IbV[I{I n B-@ONP]ar�I

ö 6

Page 19: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

?-@O?�Gc@OReW8IbV[IOm®@TJLIF]FG6?�\-@Q\�IFNHN"�¸@YV[Iv@T\�EqU6EHB�?�DFEPG6?�I�I�\�IFNHNH@tZKIFReW7I_Va@YZ[BVa@f�z�IbVuºK�§iIFNPIbjO@YZ[@NM@�Z[IF?�JKEPG6?�I�EH?cjcIbV[J[@t@YW�W-NPEH]v@YZa@gJKB�NHNH@eU6EHB�?�DFEPG6?�I�ZKVa@eUc@YZKIXI�]v@O?-@ONPIXW-Bq`GtJKBW8IbVa@YV[I�EPN jY@ONHGOV[I\�E¡��V[Iv@YÑ\�G�õ�?1I�JKE'@OJKJKEHJ�Z[I�EH?lZa@ON']F@OJKGt@eB�?oVa@YW-EP\�GQ@OB�RTIF?cZ[GT\�IFNPNM@e]bGOVKV[IF?cZ[I�\�E \Va@OEH?®f `·\-@u?�GOZ[@YV[I¯]ar�I¯EPN���V[Iv@YÑ\�G�õ�?t@/j�jEPIF?�I�W8IbVsjY@ONHGOVKE�\�E7º,s§eZa@O?cZ[GXReEH?�GOV[E n B-@O?hZ[G�W-EK`BTUOV[@O?�\�I`IOm�EP?%ReG)\�B�NHG�m)NM@�ºKÉ'§ fÛD�B�IFJLZ[G�W7IbV[]arswI�NM@�Z[IF?�JLEHG6?�I�Ib¶7I_ZKZ[EPjY@ORTIF?cZ[I�W�V[IbJKIF?cZ[I�@OE7]F@YW-E®\�IFNHNH@U6EHB�?�DbEHG6?�IX?�IbNHNp��@YV[Iv@�\�E \V[@OEH?lVKEHJKB�N^Za@�W�@YV[E @eºK�§ ¨ ºKÉ'§ f

ò�EH?�GOV[@o@Y���-EM@ORTGlW�@YV[NM@YZ[Gk\�E�ZKVa@O?�JLEPZ[GOV[E��7ò�· � ]FG6?�]v@O?-@ONPITÎ|ITUc@YZ[IgV[Iv@ONHEPDFDv@YZ[Gk]FG6?xB�?-@\�EP¶8B�JKEHG6?�I�Í × Ös`IyW7G6JKJKE^�-EHNPIe@vjcIbV[Ie@O?�]}r�IgB�?-@lV[Iv@ONPEHDFDF@ODFEHG6?�I�\�E�Z[EPW8Gl]FG6RgW-NHIFRTIb?hZa@YVKIOm¡]FG6?]v@O?-@ONPI�ÍSI�\�EP¶8B�JKEHG6?�E \�E¡Uc@YZ[I�\�E¡ZKEPW7GgÎ × f{��N¡ACB�?�DFEHG6?-@OReIF?hZKG1`Iu\�IbN Z[BZLZ[Ge@O?-@ONPG6U6G�m�]FG6?oNH@JKG6NH@g\�EP¶8IbV[IF?�DF@e]ar�IuZ[BZKZKIuNPI�Z[Ib?�JKEHG6?�E IuNPIu]bGOVKV[IF?cZ[E'@/j�Va@O?�?�GeJKIbU6?�GTEH?cjcIbVKZ[E^Z[G�¢dNM@yZ[IF?�JKEPG6?�IºKÉ'§e\�G/j)VY`@�IFJKJKI_V[I�W8G6JKEPZ[E^jO@m6ReIF?hZLV[I�NM@uºK�§eJ[@YVY`@u?�IbUc@YZ[EPjY@f3� I�W�V[IbJLZa@ODFEPG6?�E�\�IFE�ZKVa@O?�JKEPJLZ[GOV[E�7ò�· � @%]v@O?-@ONHI�Íx\�EP¶8IbV[EPJK]FG6?�G�m3@QW�@YV[EPZ=`@l\�Ed\V[G6Uc@OU6U6EdIg\�Ed]v@YV[@YZKZ[IbV[EPJLZ[EP]}r�IgU6IFG6RTIbZLV[EH]ar�IOm\-@ n B�IFNHNPIg\�IFE��7ò�· � @l]F@O?-@ONHIeÎ�mq@l]v@OB�JK@o\�IFNHNH@l\�EPjcI_V[J[@kRTGO�-EPNHE^ZY`@t\�IFNHNPIeNM@O]bB�?�IeV[EHJ�W7IbZKZKG@OU6NHE8IFNHIbZLZKV[G6?�Epfd��?lU6Ib?�IbV[IXNPI�W�V[IFJLZa@ODbEHG6?�E¡\�IFE¡�7ò�· � @y]v@O?-@ONHI�Î�JKG6?�Ge\�B�? n B�IuRTEPU6NHEPGOV[Epm�IF\`I n B�IFJLZKGTEHN®RTGOZKEPjcG�W7IbV¯]FB�E IFJKJKE®V[EPJKB�NPZa@O?�GgRTG6NPZKG�W-EK`BkBZ[EPNHEHDbDv@YZ[Epf

��NdJKEHR��8G6NHGQ]FEPVK]FB�EPZa@ONPIg\�IbN��7ò�· � `IgJKGOZLZ[G%V[@YW�W�V[IFJKIF?cZa@YZ[G�m'JKEM@tW7I_V�EHN3ZKEPW7Gl@l]F@O?-@ONHI�ÎJKEH@�W7I_V n B�IbNHNHGg@g]F@O?-@ONHI�Í f

ö 4

Page 20: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

ö��¹÷¿� ���±®��ø´��5���{8�>ù#ù �úù ���5 ��û®�"!�üt$�,+2�0q2sÄ�.�9;*�(=2;ÈhÈc*-Èh2:.�&q$1Ä{$)(T,/(+*�&3üv2"üb,/.�(=2sÊ�Ë¡Ì�'@kV[IbZ[IT\�E{W7G6NH@YV[EHDFDF@ODFEHG6?�IeW-EK`BxJKIFReW-NPEH]FIgW7G6JKJKE^�-EHNPIT\-@oB�?xW-B�?hZ[GS\�E{jEHJ�Za@k]FG6?�]FI_ZKZ[B-@ONHIo`In B�IbNHNM@�\�E¡JKIFU6B�EPZKGgV[E^W7GOVKZa@YZ[@¢

+

−+

CR

I

I

B

C

BBV BEVCCV

CEVBR

� I n B-@O?cZ[EPZY`@�EP?�]FG6U6?�EPZKI5JKG6?�GuºK����m6À���mhºK?���m6À�?�f�¾����-EM@ORTG n B�EH?�\�E)NM@�?�IF]FIbJKJKEPZ=`@�\�E n B-@YZKZKVKGI n B-@ODFEHG6?�E®]ar�IXNPIFUc@O?�GyZKVa@gNPGOV[G n B�IFJ�Z[I n B-@O?hZ[E^ZY`@f � @ONHE8I n B-@ODFEPG6?�E7W7G6JKJLG6?�GeIFJKJLIbV[IXV[EP]v@vjO@YZ[I\-@ONHNPIlV[IbNM@ODFEPG6?�E�ZKV[@~NHI%jO@YV[EPIkUOVa@O?�\�IbDFDFI1EHRgW7G6JLZ[I%\-@ON�]FEPV[]bB�EPZ[G�IbJLZ[IbV[?�GxIk\-@ONHNHI%V[IFNH@ODFEHG6?�EEHRgW7G6JLZ[I�\-@ON®ZKVa@O?�JLEHJLZ[GOVKIuJLZKIFJKJKG�f

º,?�� ¥ ¸®�"À�? - ºK��� �À�� ¥Bý �:À�? - º,��� �º,?�? ¥ ¦¼?{À�?�*�ºK?��ºK��� ¥ ¦¼�dÀ��L*|º,��� -

\�G/jcIgNPIyW�VKEHRTI�\�B�I�I n B-@ODbEHG6?�E3Va@YW�W�V[IbJKIF?cZa@O?�GoNHIy]v@YV[@YZKZ[IbV[EPJLZ[EP]}r�I�\�IFN3ZKV[@O?�JKEHJLZKGOV[Il�:V[EHJ�W7IbZL�Z[E^jO@ORTIb?hZ[I�\�E EH?�UOV[IbJKJKGeIu\�E¡B�JK]FEPZ[@ � I�NHIX@ONPZKV[I�JKG6?�GeJKIFReW-NPEH]FIFReIF?hZKIuNPIuI n B-@ODFEHG6?�E @ONPNHI�\�B�IRt@OU6NPEHIX\-@ONPNHI n B-@ONHE'EHNq]bEPV[]FB�E^Z[G�`I�]FG6JLZ[E^Z[B�EPZKG�f ¬ I�NHI�]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I�\�E3EH?�UOV[IbJKJKGQ]FGOVKV[EPJLW7G6?)�\�IF?cZ[E�@1\�EPjcIbVKJKEsjY@ONHGOV[E�\�E�ºK��� ?�G6?�\�EP¶8IbV[EHJL]FG6?�GiJLEHU6?�EP�-]F@YZ[EPjY@ORTIF?cZ[IeZKV[@SNPGOV[G�m3W7G6JLJKEM@ORTG\�IbZ[I_V[RTEH?-@YVKI�EHNhjO@ONPGOV[I�\�E)V[E^W7G6JKG�À?�þ~\�IFNPNM@�À�?�ZKVa@O]F]FEH@O?�\�G�JKB�NUOVa@Y�-]FG�\�IbNHNHI5]F@YVa@YZKZ[IbVKEHJLZ[EP]ar�I\�E¡EH?�UOV[IbJKJKGTJLZKIFJKJKIuNM@�VKIbZKZa@�\�E ]F@YV[EH]FGg\�Ib�-?�EPZ[@e\-@ONHNH@yZ[I_V[Dv@eI n B-@ODFEHG6?�IYf

ÿ����

ÿ ������

ÿ

����

�����

ÿ ���30.02

0.04

0.06

0.08

0.1

0.12

0.14

0 0.5 1 1.5 2 2.50

/ 2

Page 21: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

¾ n B�IbJLZ[GtW-B�?hZKG%W8G6JKJKEM@OReGT]FG6JLZKVKB�EPV[I�NH@tVKIbZKZa@T\�E3]F@YV[EH]FGt]bGOVKV[EHJ�W7G6?�\�IF?cZ[Ig@ONHNM@g· n f3� ö � JKB�NW-EM@O?�GS\�IFNPNHIQ]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�It\�E�B�JL]FEPZa@1IQEH?�\�E^jEP\�B-@YV[ItEsjY@ONHGOV[E�\�EsV[EPW8G6JKGS\�IFNHNH@1À���þ \�IFNHNH@À��|I�ºK����þ�\�IFNHNH@tºK����\-@ONHN"��EH?cZ[IbVKJKIFDFEPG6?�IX\�E®Za@ONHI�V[IbZKZ[@g]FG6?oNH@g]v@YV[@YZKZ[IbV[EPJLZ[EP]v@�V[IbNM@YZ[E^jO@�@ONHNH@À�?�þ�W�V[EPRt@g\�I_Z[IbV[RTEP?-@YZa@m-]FG6ReW-NPIbZa@O?�\�Ge]bG6J�` ·'NH@e\�IbZ[I_V[RTEH?-@ODbEHG6?�IX\�IbN W-B�?cZ[Gt\�E NM@vjcGOV[Ge\�IFNZKVa@O?�JLEHJLZ[GOVKIO¢

����� ��� ��� ��� ��� ��

�� �� ���

���

���

� ���� �

� �! #"

$ ��" %'&

(�)

�'@kW�V[G)]FIb\�BVa@�JLIFU6B�EPZa@kW-Bq`G1IbJKJKIbV[IQJKIbReW-NHE^�-]v@YZa@o?�GOZa@O?�\�G1]ar�ItEH?�DFG6?-@1@YZLZ[EPjY@k\�EPVKIbZKZa@oNH@ºK?���?�G6?kJKE¡\�EHJL]FG6JLZa@�\-@tº,[eW-EK`Bk\�E�2fH´b��2fH´ / ¼ym�W7IbV�]FB�E®W7G6JLJKEM@ORTGg@OJKJKB�ReIbV[IOm-JKIF?�DF@e]FG6Rg�RTIbZLZ[IbV[I�IbVKV[GOVKE'JKEPU6?�EP�-]v@YZKEPjE"m�ºK?��+*Ϻ,[-f���?kZa@ON ]v@OJKGT?�G6?x`I�W-E[`Bo?�IF]bIFJKJ[@YV[EPGTV[EH]bGOVKV[IbV[I�@ONHNHI]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�EdEH?�UOV[IFJLJKG�fgØ�@ONPNM@QI n B-@ODFEPG6?�Ig\�IbNHNHI�]v@O\�BZ[Ig\�E�Z[IF?�JKEPG6?�IeJKB�NPNM@lRT@OU6NHEM@T\�EEH?�UOVKIFJKJKGTGOZLZ[IF?�EM@OReG�\�E^V[IbZKZ[@ORTIF?cZ[I

À�? ¥ º,?�? ¨ º,[¦B? -

I�W7IbV¯EHN®V[IFJLZKGeJKE®W�V[G�]FIF\�I�?�IFN¡RTG�\�GgU6EÇ`@�j)EHJLZ[G�f��N8]bEPV[]FB�E^Z[G�\�E8W8G6NM@YV[EPDFDv@ODFEPG6?�I�IFJ[@ORTEP?-@YZ[GXW�V[IbJKIF?cZa@�EHN�jY@O?cZa@OU6U6EHG�\�IbNHNM@�A;@O]FEPNHE^ZY`@X\�E7@O?-@=�

NHEPJKEpmhRt@�r-@�@O?�]ar�I�UOVa@vjE-EH?�]FG6?cjcIF?�EPIF?hZKEpm)Za@ONPE-\-@uV[IF?�\�IbVKNHGXVa@YV[@ORTIF?cZ[I¯BZ[EPNHEPDFDv@YZ[GuEH?eW�Va@YZKEH]v@f, NPEsEP?�]FG6?hjcIb?�EHIF?cZ[E5]FG6?�JKEPJLZ[G6?�G�?�IFN�A;@YZKZKG1]}r�I%EHN{W-B�?hZKGi\�E�NM@vjcGOV[G�`ItACGOVKZ[IFRTIb?hZ[ItNPIFUc@YZ[GS@OEW�@YVa@ORTI_ZKV[Es\�IbN5\�EHJLW8G6JKEPZ[E^jcGSIOm�JLGOW�Va@YZKZ[BZKZKG�m3jO@YV[EH@S@ONsjO@YVKEM@YV[It\�IFNPNM@1Z[IFReW8IbVa@YZ[BV[@fS��?�A;@YZL�Z[E"m JLIgW7I_VXIFJLIFReW-EHGlNM@tZ[IFReW8IbVa@YZ[BV[@l@OB�RTIb?hZa@m¡\�EPRTEH?hB�EHJK]bIgNH@oºK?��ÿ?�IF]FIFJKJK@YV[EM@lW8IbVX@/jcIbVKIB�?-@�\-@YZa@�À�?¯fÿØ�E�]FG6?�JLIFU6B�IF?�Dv@�@OB�RTIF?cZa@�NM@x]FGOVKVKIF?hZKI�\�E���@OJKI1I n B�EH?�\�E�@O?�]}r�I n B�IFNHNH@\�EsIbRTIbZKZ[E^Z[GOV[IOm']v@OB�J[@O?�\�GSB�?xB�NPZKIbV[EHGOVKITEH?�]bVKIFRTIF?cZ[G1\�IFNPNM@lZ[IbReW7IbV[@YZ[BVa@o\�IFNPNM@kU6EPB�?�DFEHG6?�IOf¬ Esr-@ n B�EH?�\�E�B�?�ReIF]F]v@O?�EPJKRTGk]ar�It]FG6?�\�B�]bIl@oACGOVLZ[E�JL]FG6JLZa@ORTIb?hZ[E�\-@ON�W-B�?cZ[GS\�E{VKEPW7G6JLG1IW-Bq`GtW7GOVKZ[@YV[I�@O?�]ar�I�@ONHNM@T\�EPJLZKV[B�DbEHG6?�I�\�IFN3\�EPJLW7G6JLEPZ[E^jcG�f���?�JKIbV[Ib?�\�GkB�?-@TV[IFJKEPJLZ[IF?�DF@QEP?SJKIbV[EPI@ONHN"��IFReIbZKZ[E^Z[GOV[I�JKEqGOZLZ[EHIF?�IXB�?1?�GOZ[IbjcG6NHIXRTEHU6NPEHGOVa@ORTIb?hZ[G�mW8IbV[]arswI�B�?SIbjcIF?cZ[B-@ONHIXEH?�]bV[IbRTIF?cZ[G\�E7]FGOVLV[IF?cZ[I�W7GOVKZa@y@�B�?l@OB�RTIF?cZ[Gy\�IFNHNH@y]F@O\�BZa@�JLB�NHNM@�V[IbJKEHJLZKIF?�Dv@y\�E7IFRTIbZLZ[EPZ[GOVKI�I n B�EP?�\�E¡@B�?-@e\�EPRTEH?hB�DFEHG6?�I�\�IFNPNM@Tº,?���m�]ar�Iu]FG6?hZLVa@OJLZa@eN"��GOV[EPU6EH?-@YV[EPG�@OB�RTIF?cZ[Ge\�E¡]FGOVKVKIF?hZKIO¢

+

−+

IB

ER

C

CR

BBV BEVCCV

CEVBR

I

/ ´

Page 22: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

��N�]F@ONH]FG6NPG�\�IFN�W-B�?cZ[G�\�EhV[EPW8G6JKG�EH?uW�V[IFJKIF?�DF@�\�E�B�?-@¯V[IFJKEPJLZ[IF?�DF@�\�E)IFRTI_ZKZ[EPZKGOV[I�`I�W-E[`B�]FG6RgW-NHIFJ��JKG�mW8G6EH]ar�wIuNPIu\�B�I�Rt@OU6NPEHIOm n B�IFNHNH@�\�E B�JL]FEPZa@yI n B�IFNPNM@y\�E®EH?�UOV[IFJLJKG�m-?�G6?kJKG6?�G�W-E[`B%\�EHJ[@O]F]bGOW�W-EM@YZKIOm n B�EP?�\�E®?�G6?x`I�W-E[`BlW8G6JKJKE^�-EHNHI�]v@ONP]FG6NM@YVKI�NH@�À?�EP?�\�EPW8IF?�\�IF?cZ[IFRTIF?cZ[Iu\-@ONHNM@y]FG6?�G6JK]bIF?�Dv@\�IFNPNM@�À���f�z�IbV{B�?-@�jY@ONHBZa@ODbEHG6?�I5IFJ[@YZLZa@�\�IFNW-B�?hZKGu\�EV[E^W7G6JKG��-EPJKG6U6?-@�VKEH]FGOVKVKIbV[I�@�W�V[G)]FIb\�BV[IUOVa@Y�-]ar�I5@Y����@OJLZ[@O?�Dv@¯]FG6ReW-NPIFJKJKI�G�@�W�V[G�]FIF\�BV[Is?�B�RTI_V[EH]ar�I�E^Z[IbVa@YZ[E^jcIOm+]}r�Is?�G6?�W�V[IF?�\�IbV[IbRTGEH?~IFJ[@ORTIOf ½ G6?�JKEH\�IbVKIbV[IFRTGkEH?cjcIF]FIeB�?~]v@OJKGkW�@YVKZKEH]FG6NH@YV[RTIF?cZ[IyJKIFReW-NPEH]FIYmq]ar�Ie]FGOVLV[EHJLW8G6?�\�I@ONHNH@�RT@OU6U6EHGOVa@O?�Dv@y\�IFNPNHI�JKEPZ[B-@ODbEHG6?�E¡]ar�IXJKE¡EH?�]bG6?hZKV[@O?�GT?�IFNHNH@�W�Va@YZKEH]v@f

��?�?-@O?�DFE^Z[BZKZ[G%jO@Q\�IbZKZ[Gl]ar�Ig?�IFEd]FE^V[]FB�E^Z[E�\�E�W7G6NM@YVKEHDFDv@ODbEHG6?�I�jEPJLZ[E3�-?�GOVa@i`I�?�Ib]FIFJKJ[@YVKEHG\�EHJ�W7GOVKV[I�\�Eq\�B�I�U6Ib?�IbVa@YZ[GOV[E'\�EHJLZKEH?cZ[Ep¢¯ºK?�? IyºK����f ½ E�`GTV[@YW�W�V[IFJKIF?cZ[IbVKIb���7IgEH?oW�Va@YZ[EP]v@tB�?UOV[G6JKJLGQW�VKGO�-NHIFRt@tI�JKEq]FIbV[]v@QEH?cjcIF]FIy\�E�@vjcIbV[IyB�?�B�?�EH]FGQU6IF?�I_Va@YZ[GOV[Iy\�E�@ONPEHRTIF?cZa@ODFEPG6?�IXW7I_VRTG6N^Z[E�ZKV[@O?�JKEHJLZKGOV[Epf�¼�IF\�EM@ORTG�]bG6RTI�JKE7W-Bq`GgW�@OJLJ[@YV[I�\-@�\�B�I�U6IF?�IbV[@YZ[GOV[E®\�E¡@ONHEPRTIF?cZa@ODFEPG6?�I�@B�?�GkJLG6NPZa@O?cZ[GQ?�IFNd]FEPVK]FB�EPZ[Gl@YW�W7Ib?-@l]FG6?�JKEP\�IbVa@YZ[G�¢���@OJ�Za@%BZKEHNHEPDFDv@YV[Igº,��� @ON3W8G6JLZ[G%\�E{ºK?�?IXjY@YV[EM@YVKI�¦¼?¿GOW�W7GOVLZ[B�?-@ORTIF?cZ[IOm7EP?1RTG)\�Gg\-@tGOZKZ[IF?�IbVKI�NM@TJLZKIFJKJ[@T]FGOVLV[IF?cZ[I�\�Eq��@OJKI�]ar�I�JKEJ[@YV[I_���7IXGOZLZ[IF?hBZa@e]FG6?oºK?�?�f{Ø�Ib�-?�EM@OReGg¦¼Ý? NM@y?�B�G/jO@g¦B?�f

+

−+

ER

ICCR

IB

BEVCCV

CEVBR’

�{�¸@ONPZLV[GkEP?�]FG6?hjcIb?�EHIF?cZ[ITW�V[EPRt@%]bEPZa@YZ[Gl]FG6?�JKEPJLZ[IT?�IFN{A;@YZKZ[Gk]}r�IeEHN�W-B�?hZKG1\�E�NH@/jcGOV[Gl\�EPW8IF?�\�IACGOVKZ[IbRTIF?cZ[It\-@ONHNPIT]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�ItEH?cZKV[EP?�JKIF]ar�I%\�IFNsZKVa@O?�JLEHJLZ[GOVKIOm�NHI n B-@ONHE�W8G6JKJKG6?�G1jY@YV[EM@YV[I?�GOZ[IbjcG6NPRTIF?cZ[IOm'@l]v@OB�JK@k\�IFNHNH@l\�E^W7IF?�\�IF?�DF@o\-@lW�@YVa@ORTIbZLV[E�]FG6JLZKVKBZKZ[EPj)E�]FG6RTI�NM@%NM@YV[U6r�IFDbDv@\�Eq��@OJKI�]ar�Iy?�G6?SW7G6JKJKG6?�GQIFJLJKIbV[Iy]FG6?cZKV[G6NPNM@YZ[E']FG6?SUOVa@O?�\�I�W�V[IF]FEPJKEHG6?�IOf���Nq]bEPV[]FB�E^Z[GQ]ar�IyW-EK`BJLW8IFJKJKG�JKE5BZ[EPNHEHDbDv@oW7IbVyNH@1W8G6NM@YV[EPDFDv@ODFEPG6?�It\�IFE���� � V[EPJKG6NPjcIQ@O?�]ar�I n B�IFJLZKGSW�VKGO�-NHIFRt@1ItJKE��@OJ[@�JKB�NHN"��EHRgW-EHIFU6G�\�E¡B�?kW�@YVKZ[E^Z[GOV[Ik��W7IFJ[@O?cZ[IF�gW7IbV��-JKJ[@YV[IXNM@�Z[IF?�JKEPG6?�IX\�E¡��@OJKIOfz�IbV%W�@YVKZ[E^Z[GOV[ISW7IFJ[@O?cZ[IiJKE�EH?cZ[IF?�\�I~B�?¿W�@YVKZ[EPZKGOV[I1V[Iv@ONHEPDFDv@YZ[G�]FG6?ÐVKIFJKEHJ�Z[IF?�DFI�Za@ONHE�\-@�A;@YVW�@OJKJ[@YVKI�B�?-@X]FGOVKVKIF?hZKI¯RTG6N^Z[GuRT@OU6U6EHGOV[I�\�E n B�IFNPNM@u]ar�I�\-@uZa@ONHI�W�@YVKZ[E^Z[GOV[I�jEHIb?�I�\�IbVKEPjY@YZa@m�EP?n B�IbJLZ[GQ]v@OJKGtW�@YVKZ[EP]FG6NM@YVKI�NM@t]FGOVKVKIF?hZKI�\�E'��@OJKIOf���?SB�?-@QZa@ONPI�JKE^Z[B-@ODFEHG6?�I�NH@TZ[IF?�JKEPG6?�I�]}r�IyJKEGOZKZ[EPIF?�I�]FG6?�EHNqW�@YVLZ[EPZ[GOVKIQ`I�JLG6JLZa@O?�DFEH@ONHRTIF?cZ[I�\�IbZKIbV[RTEP?-@YZa@T\-@ONqVa@YW�W8GOVKZ[G%\�IFNHNPI�V[IFJKEPJLZ[IF?�DFIYfz�IbV[]arswI n B�IFJ�Za@y@YW�W�V[G6JKJKEPRt@ODFEHG6?�I�JLEM@�jO@ONPEH\-@t`I�?�IF]FIFJLJ[@YV[EHG�]ar�I�NM@�]FGOVKV[Ib?hZ[I�?�IFNPNHI�V[IFJLEHJLZ[Ib?�DFIJKEH@1@ONHRTIF?�G%jcIF?cZ[E�jcG6N^Z[IgW-EK`BxUOVa@O?�\�It\�E n B�IFNHNH@k\�E���@OJKIYflØ�E{JKG6NHE^Z[G�m3?�IFNPNM@lV[EPJKG6NHB�DbEHG6?�IT\�IFE]FE^V[]FB�EPZKEpmJKE8A;@yN"��E^W7GOZ[IFJLE8\�E8W�@YVKZKEPZ[GOV[I�W8IFJ[@O?cZ[I�I�W7G6E7JLE8jcIbV[E^�-]v@g@ON�Z[IbV[ReEH?�I�JKI�NH@yÀ?�ZKV[G/jO@YZ[@`I�]FG6?�JKEHJ�Z[IF?cZ[I�]FG6?oN"��E^W7GOZ[IFJLE®JLZ[IFJKJK@f

��IFNPNp��EPW7GOZKIFJKE8W�@YVKZKEPZ[GOV[I�W8IFJ[@O?cZ[I�W7G6JKJKEH@ORTG�\�B�? n B�I�JK]bVKEPjcIbV[I�]ar�I�NM@�Z[IF?�JKEPG6?�IXº,?�\�IFNHNH@��@OJKI�V[EHJLW8IbZKZ[Ge@gRt@OJLJ[@l`I�\-@YZa@g\-@

ºK? ¥ ºK��� ¦u ¦ ¤ *Ó¦u  «/6Ô

Page 23: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

+

−+

E CCVBE

CR

V

CEV

ER

IB

1R

2R

IR2

IR1

IC

I

¬ I�JKBW�W8G6?�EM@ORTGt]ar�IyNM@eZ[Ib?�JKEHG6?�IgºK?��¿JKEH@TW�@YV[E3@%º,[-m8W8G6JKJKEH@ORTGTJKB�-E^Z[GQ\�IbZ[IbV[ReEH?-@YV[Iyº,��¢ºK� ¥ º,? ¨ º,[-fÖD�B�EH?�\�E

À�� ¥ ºK? ¨ º"[¦B� «

¬ E�?�GOZ[E-]}r�I¯EH? n B�IFJLZ[G�]F@OJKG�À���`I¯J�Za@YZa@XJK]bIFNPZa@u]FG6RTI�B�JK]FIF?cZ[I�\-@ONHN"��IFReIbZKZ[E^Z[GOV[IOm6EP?TRTG)\�G�]ar�I@Y���-EM@gJKIFU6?�GeW8G6JKEPZ[E^jcG�mW7IbV¯B�?-@eRt@OU6U6EPGOV[I�]FG6RTG)\�E^ZY`@y?�IFE¡]v@ONH]FG6NPEpfÛò8@O]F]bEM@ORTG�GOVa@gN"��E^W7GOZ[IFJLEpm@O?�]ar®��IFJLJ[@Ó\-@�jcI_V[EP�-]v@YVKI~@ON�Z[I_V[RTEH?�IYm�]ar�IiÀ�?.- À���f²��?¿Za@ON�]v@OJLGÓÀ��/* À�� I n B�EH?�\�EW7G6JLJKEM@ORTGX]v@ONH]FG6NH@YV[I¯NH@�]v@O\�BZa@�JKBQ¦¼�xBZ[EHNPEHDFDF@O?�\�G�EHN-jO@ONPGOV[I�\�E8À��]ar�I�@Y���-EM@OReG�GOZKZ[IF?hBZ[G�¢

º,� ¥ ºK��� ¨ ¦¼�dÀ�0*ÿºK��� ¨ ¦¼�{À���«Ø�B�? n B�I

ºK��� ¥ ºK��� ¨ ¦¼�{À� ¨ ºK?�*�º"[�«·sJLJKIF?�\�G�@ n B�IFJLZ[G~W-B�?cZ[Gx?�GOZ[IoºK��� IlÀ���msW7G6JKJLEM@ORTGi\�IbZ[IbV[ReEH?-@YV[IlÀ�? \-@ONPNHIl]v@YVa@YZKZ[I_V[E^�JLZ[EP]ar�Ii\�E�B�JK]bEPZa@�ISIFRTIbZKZKEPZ[GOV[I1]bG6R�B�?�IYm�EH?�\�E^jEH\�B-@O?�\�G�EHN�W-B�?hZ[G�\�E�V[EPW8G6JKG�EH\�IF?cZ[EP�-]F@YZ[G\-@�Z[@ONHE�jY@ONHGOV[E5IlGOZKZ[IF?�IF?�\�GiNM@�À�?�]FGOVKV[EPJLW7G6?�\�IF?cZ[IkW8IbVgEH?cZ[IbVKW8G6NM@ODFEPG6?�IOf�Ø�GO���-EH@ORTGiGOV[@jcIbV[E^�-]v@YV[It]ar�ItJKEH@O?�G1Ib¶7IbZLZ[EPjY@ORTIF?cZ[ITJKG�\�\�EHJKA;@YZLZ[ItNHIT\�EPJKB�U6B-@OU6NHEH@O?�DFITV[IFNH@YZ[EPjcIe@ONHNPITEPW8GOZ[IFJKEW�V[IF]bIF\�IF?cZ[IFRTIF?cZ[I�A;@YZKZKIO¢

À?+- À �3¤À?+- À���«

¬ E�?�GOZ[E�]ar�IlW7I_VeJKG�\�\�EHJKA;@YVKIkNM@SW�V[EHRT@S\�IbNHNHIl\�B�Ik\�EPJKB�U6B-@OU6NHEH@O?�DFIl?�G6?ÓJKE�W-Bq`G�EH?�]_V[IFRTIF?)�Za@YV[Ig@YVK�-E^ZKVa@YV[EH@ORTIF?cZ[I�À �3¤ m¡\�EHRTEP?�B�Ib?�\�GoEHN3jY@ONHGOV[Iy\�IFNPNHIyV[IFJKEPJLZ[IF?�DbIe\�IFN�W�@YVKZ[E^Z[GOV[IOm®W8IbV[]ar�wI@ONPZLV[EHRTIb?hZ[Eq@/j�V[IFRTReGTB�?~IF]b]FIFJKJKE^jcGl]bG6?�JKB�RTG%\�E3]FGOVKV[Ib?hZ[I�IyB�?®��IF]b]FIFJKJKE^jO@%\�EHJKJLEPW�@ODFEPG6?�I�\�EW7GOZKIF?�Dv@¯JKB�NhW�@YVKZ[E^Z[GOV[IOf ¬ GOZKZ[G6NHEP?�IFEM@OReG¯@O?�]ar�I�EPNhA;@YZLZ[G�]ar�I�]FG6?�N"��E^W7GOZ[IFJLEh\�EcW�@YVKZ[E^Z[GOV[IdW7IFJK@O?)�Z[I�JKG/j)Va@OJLZKEHRTEH@ORTGyNM@y]FGOVKV[IF?cZ[I�\�E®��@OJKIT�:W7G6EP]ar�wIXEPW8GOZ[EHDbDFEM@ORTGyB�?kjY@ONHGOVKIu\�EqºK?���RT@OU6U6EHGOV[I\�E n B�IFNHNPG¯V[Iv@ONPI � m n B�EH?�\�E�?�G6?�]O�H`IsEHNcV[EHJK]ar�EPG�]}r�I5NH@�jcIbV[E^�-]v@�@�W8G6JLZ[IbV[EPGOV[Eh]FE�ZKV[@OU6Uc@¯EH?�EP?�Uc@O?�?�G�"N"��Ib¶8IbZKZ[E^jO@y]FGOVKV[Ib?hZ[Iu\�E®��@OJKIXJ[@YV=`@e]FG6RyB�? n B�I�RTEH?�GOVKI�\�E n B�IbNHNM@yJLZ[EPRt@YZa@ � f

Ø�@OE¡V[EHJKB�N^Za@YZ[E¡GOZKZ[Ib?�BZ[E ?�IFNPNp�¸@O?-@ONPEHJKE \�IFN ]FEPVK]FB�EPZ[Ge\�E W8G6NM@YV[EPDFDv@ODFEPG6?�IX]FG6?oW�@YVKZKEPZ[GOV[I�W7I_�J[@O?cZ[IgVKEHJKB�N^Za@%I_jEH\�Ib?hZ[Ig]FG6RTIyEHN3W-B�?cZ[Go\�EdNH@/jcGOV[G%JKEH@%�-JKJ[@YZKG�m'IF]b]FIbZKZ[Gl]ar�IgW7I_VXNH@%À�?�m'\-@OEjY@ONHGOV[E\�IbNHNHI n B-@YZLZKV[G�V[IFJKEPJLZ[IF?�DbI�BZ[EPNHEPDFDv@YZ[I�I�\�EPW7Ib?�\-@uRTG6N^Z[G�W7G�]FGu\-@ONPNHI�]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�EH?)�ZKV[EP?�JKIF]ar�I¯\�IbNZKVa@O?�JKEPJLZ[GOV[IOm6V[EPJKG6NPjcIb?�\�G n B�EH?�\�E�EHNW�VKGO�-NHIFRt@�]ar�I�IbVa@uJ�Za@YZ[G�W�V[IF]FIb\�IF?hZKIFRTIF?cZ[IRTIFJLJKGeEP?kIbj)EH\�IF?�Dv@f

/O¹

Page 24: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

û®�;ÂÆüt$�,+2�0q2sÄ�.�9;*�(=2;ÈhÈc*-Èh2:.�&q$1Ä{$)(T,/(+*�&3üv2"üb,/.�(=2s*�$21�$�,v,/.~032546*�É�Ä�.�'@XW7G6NM@YVKEHDFDv@ODbEHG6?�I¯\�IbE�ZKVa@O?�JLEHJLZ[GOVKE8@XI_¶7IbZKZKG�\�E8]v@ORgW7GXJLE8GOZKZ[EPIF?�I¯]bG6?TV[IbZ[E�RTG6NPZKGuJKIbReW-NHEP]FEpmUOVa@ODFEPIe@ONdA;@YZKZKGk]ar�ITNp��@OJKJKGOVK�-EPRTIF?cZ[Gk\�Ed]FGOVLV[IF?cZ[IT\-@%W�@YVLZ[Ie\�IFN{Uc@YZ[Il`IgZKV[@OJK]FBVa@Y�-EPNHIeI�]ar�IEHN�W�V[GO�-NPIFRt@%\�IFNHNH@lACB�Uc@lZ[I_V[RTEH]F@%?�G6?�JLE{W8G6?�IOfez{V[IF?�\�EM@OReGkEH?�?-@O?�DbEPZ[BZKZKGkEH?~IFJ[@ORTI n B�I_�JLZv��B�NPZ[EPRTGeW-B�?cZ[G�¢�@vjcIbjY@ORTGej)EHJLZ[Gt]ar�Iy?�IFN3]F@OJKGQ\�IFE���� � NH@eV[IFJKEPJLZ[IF?�Dv@Q\�E3IFReIbZKZ[E^Z[GOV[IXI_Va@EH?�\�EPJLW7Ib?�J[@Y�-EHNPIlW7I_VTGOZKZ[Ib?�IbV[I%B�?-@~JLZa@Y�-EPNHEHDbDv@ODFEHG6?�I%\�IFN5W-B�?cZ[G�\�E�NM@vjcGOV[G�\�IFN�ZLVa@O?�JKEHJ�Z[GOV[IOfD�B�IFJLZa@xIbVa@�NH@~]FG6?�JKIbU6B�IF?�Dv@�\�IFN¯A;@YZKZKGx]}r�I1?�IbN���� � NH@�]FGOVKV[Ib?hZ[Ix`IlZKVa@OJLW8GOVKZa@YZa@iW�VKIbjO@=�NHIb?hZ[IbRTIF?cZ[It\-@oW7GOVKZa@YZKGOV[EsRTEP?�GOV[EPZ[@YV�Ç·pm'NM@o]FB�E�]bG6?�]FIF?cZKVa@ODFEPG6?�Il\�E^W7IF?�\�IQACGOVKZ[IbRTIF?cZ[It\-@ONHNH@Z[IFRgW7IbVa@YZKBVa@f���IFN-]v@OJKGu\�IFE�ZLVa@O?�JKEHJ�Z[GOV[E�@uIb¶8IbZKZ[GX\�E�]F@OReW7GuNM@�]FGOVKV[IF?cZ[I¯j)EHIF?�I�ZKVa@OJ�W7GOVKZa@YZ[@\-@�W7GOVKZ[@YZ[GOV[E�Rt@OU6U6EHGOV[E^Za@YV�Ç·5NH@�]FB�E¯]FG6?�]bIF?hZLVa@ODFEHG6?�I�`IoW�Va@YZKEH]v@ORTIb?hZ[IkEH?�\�EPW8IF?�\�IF?cZ[IS\-@ONHNH@Z[IFRgW7IbVa@YZKBVa@gIuNM@g]bB�E'RTGO�-EPNHE^ZY`@�\�EHRTEP?�B�EPJK]FI�@ONPNp��@OB�RTIF?cZa@YV[I�\�IFNHNH@gZ[IFRgW7IbVa@YZKBVa@f�z�I_VKZa@O?cZ[G?�IFE{ZKVa@O?�JKEPJLZ[GOV[E�@kIb¶8IbZKZ[Go\�E�]v@OReW8GkNM@l]FGOVKV[IF?cZ[ITZ[Ib?�\�It@k\�EHReEH?hB�EPV[Ie@ONHNp��@OB�RTIF?cZa@YV[Ig\�IFNHNH@Z[IFRgW7IbVa@YZKBVa@m�]FG6?oB�?-@�]FG6?�JKIFU6B�IF?cZ[I�JLZ[@Y�-EHNHEPDFDv@ODFEPG6?�I�ZKIbV[RTEP]v@�EP?hZLV[EH?�JKIb]v@f

z�IbV�W7G6NH@YV[EHDbDv@YV[I�B�?iZKVa@O?�JLEHJLZ[GOVKIe�7ò�· � JK@YV[Ib���7I n B�EP?�\�E{JLBÙT]FEPIF?hZKIeB�?�GkJL]}r�IbRt@l\�IFNZ[E^W7GoV[E^W7GOVKZa@YZKG1EH?x�-U6BVa@md\�G+jcI%º,ÛµACGOV[?�EHJK]bI%NH@kZ[IF?�JKEPG6?�IQ\�EsW7G6NH@YV[EHDFDF@ODFEHG6?�IT?�Ib]FIFJKJ[@YVKEM@W7I_V�EHNd\Va@OEP?~ITºKÉ�É ACGOV[?�EHJK]bITNp��GOW�W7GOVKZ[B�?-@QZ[IF?�JKEPG6?�Ie?�IFUc@YZKEPjY@k@ONdUc@YZ[Ik�"NM@QW�V[IFJKIF?�DF@o\�IFNHNH@V[IFJLEHJLZ[Ib?�Dv@�¦¼É `I1?�Ib]FIFJKJ[@YVKEM@�W8IbV%IbjE^Za@YV[Io\�E�]bGOVKZ[G)]bEPV[]FB�E^Za@YV[I1N"��IbjcIF?cZ[B-@ONPI�U6Ib?�IbVa@YZ[GOV[I1\�EJKIFU6?-@ONPIX]FG6?�?�IbJKJKGt@ON¡Uc@YZ[IOf

>�?kZa@ONPIu]bEPV[]FB�E^Z[Ge?�G6?oVKEHJKB�N^Za@�W8IbVY`GT]FG6?cjcIF?�EPIF?hZKI�\-@ON®W-B�?hZ[Gt\�E¡jEPJLZa@�W�Va@YZ[EP]FG�m�W8IbV[]arswI�]FG6?)�Z[EPIF?�Io\�B�IoU6IF?�I_Va@YZ[GOV[E�\�E�ZKIF?�JKEHG6?�IYm�B�?�Gx\�IbE n B-@ONPE�\�IbjcIoACGOV[?�E^V[IoB�?-@~Z[IF?�JLEHG6?�Io?�IFUc@YZKEPjY@V[EPJLW7IbZLZ[Gt@gRT@OJKJ[@eIu?�G6?kW-Bq`G n B�EP?�\�E'IFJLJKIbV[IXVKIv@ONHEPDFDv@YZ[Gg]FG6?1B�?-@eJKIFRgW-NHEH]bIuW�@YVKZ[EPDFEHG6?�Iu\�IFN^�NM@QZ[IF?�JKEPG6?�Ie\�E�@ONHEPRTIF?cZa@ODFEHG6?�Igº,Û�fgz�IbVuZa@ONHI�RTGOZ[E^jcG n B�IFJLZKGo]FEPVK]FB�EPZ[Gl?�G6?|`I n B-@OJKEdRt@OEBZ[EPNHEHDbDv@YZ[GeEP?lW�Va@YZKEH]v@�I�@ON¡JKB�GeW8G6JLZ[GeJLE V[IF@ONHEHDbDv@ n B�IFNHNPGgV[E^W7GOVKZa@YZKGg\�E JKIFU6B�E^Z[G�m-]FG6?�JKEHJ�Z[IF?cZ[I?�IFNPNM@g]bG6JKEH\�\�IbZLZa@T@OBZ[GOW8G6NM@YV[EPDFDv@ODFEPG6?�I�\�IbNq�7ò�· � ¢��? n B�IFJLZKGt]FEPV[]bB�EPZ[GQNM@�V[IFJKEPJLZ[IF?�Dv@Q¦u§�\q`@TNPB�G6U6GQ@TB�?-@Q]F@O\�BZa@t\�EqZ[IF?�JKEPG6?�I�]FGOVKV[EPJLW7G6?�\�Ib?)�Z[IQ@ONPNM@SºKÉ'§�?�IF]bIFJKJ[@YV[EH@�W8IbVyNM@oW7G6NH@YV[EHDbDv@ODFEHG6?�I��:JKEsW�@YV[NH@kW�V[GOW�V[EHGSW7I_V n B�IFJLZKG�ReGOZ[EPjcGo\�E@OBZ[GOW8G6NM@YV[EPDFDv@ODFEPG6?�I � m�RTIF?cZKV[ItNH@o¦¼É r-@1NM@oACB�?�DFEPG6?�IQ\�Es�-JKJ[@YV[IQEPN�Uc@YZ[It@ON{W7GOZ[IF?�DbEM@ONHIt\�ERt@OJKJK@m�JKIF?�Dv@eW8IbVa@ONPZLV[Ge]FGOVLZ[G)]FE^V[]FB�E^Za@YV[I�EHN¡Uc@YZ[I�JLZ[IFJLJKGt@gRT@OJKJ[@f{�q@�¦BÉÓW-Bq`GT@O?�]}r�I�@/jcIbVKI\�IFEsjY@ONHGOVKE{W-EPBZKZ[G6JLZ[G1IbNHIbjY@YZ[Epmq\�IFNHN"��GOV[\�EP?�It\�IFEsRTIbUc@OG6r�RomqJKIb?�Dv@1]}r�IQJKB�\�E�IFJKJ[@1JKE�Rt@O?�E^�ACIFJLZKE{B�?-@%]v@O\�BZa@%\�E3Z[IF?�JKEPG6?�IgRTEPJKBVa@Y�-EPNHIOm¡\-@YZ[G%EHNqW-EP]F]FG6NPEHJKJKEPRTGQjO@ONPGOV[Iy\�IFNHNH@%]FGOVLV[IF?cZ[Ig\�EUc@YZ[Il�"]ar�IgVKEH]FGOV[\�EH@ORTGQ]FGOVKV[EPJLW7G6?�\�Ie@ONHNH@%]FGOVLV[IF?cZ[Ie@YZLZKVa@vjcIbV[JKGlB�?-@lU6EHB�?�DbEHG6?�IyW7G6NM@YVKEHDFDv@YZ[@EH?cjcIbV[JK@ORTIF?cZ[I � f{z�G6JKJKEH@ORTGgJL]bV[EPjcI_V[IXB�?®��I n B-@ODFEPG6?�IXRTG6N^Z[GyJKIFReW-NPEH]FIY¢

À ¥©¨ ºKÉ'§¦u§ -/Yö

Page 25: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

]ar�I�]FGOVKV[EPJLW7G6?�\�IYm8JKB�N W-EM@O?�GT\�IFNPNM@gZLVa@O?�JK]v@YVa@YZLZ[IbV[EPJLZ[EH]F@eEH?�UOV[IbJKJKGY�ÕB�JL]FEPZa@m7@eB�?-@eV[IbZKZ[@m�W�@OJ��J[@O?cZ[IeW8IbV�Np��GOV[EHU6EP?�IgIg]FG6?�W7Ib?�\�IF?�Dv@oW�@YV[E�@ ¨ ´+­Y¦u§¡fT��NdW-B�?cZ[G1\�E�NH@/jcGOVKGo]FGOVKV[EPJLW7G6?�\�I_VY`@@ONHN"��EP?hZ[I_V[JKIFDFEPG6?�I�ZLVa@%Za@ONPI�V[IbZKZa@%IgNH@QZLVa@O?�JK]v@YVa@YZLZ[IbV[EPJLZ[EH]F@lJLZ[IbJKJ[@f�z�IbV n B-@O?hZKGlV[EPU6B-@YV[\-@lNH@Rt@OU6NPEM@T\�E�B�JK]FE^Za@i`I�W8G6JKJKEP�-EPNHIyJK]bVKEPjcIbV[I�B�?®�¸@ON^ZKVa@QJKIFReW-NPEH]FIyI n B-@ODFEHG6?�IYm ]ar�Ig]FE3W7IbVKRTIbZKZ[I�\�E]v@ONP]FG6NM@YV[I�NM@eºK�§ ¢

ºKú ¥ À�u�"¦¼ *Ó¦u§ � *�ºK�§ «

`· n B�EH?�\�E¡W7G6JLJKEP�-EPNHIuVKIv@ONHEPDFDv@YV[I�B�?k]FEPV[]bB�EPZ[GT]ar�Iy@YW�W�V[G6JLJKEHRt@�B�?1U6IF?�IbVa@YZKGOV[I�EH\�IF@ONHIX\�E ]FGOVL�V[IF?cZ[IlBZ[EHNPEHDFDv@O?�\�G�JKIFRgW-NHEH]bIFRTIF?cZ[I%B�?�ZKVa@O?�JLEHJLZ[GOVKIk�7ò�· � I%B�?-@�VKIFJKEHJ�Z[IF?�Dv@m�]bG6RTIQ?�IFNHNPGJK]ar�IFRt@�\�E7JLIFU6B�EPZ[G�V[E^W7GOVKZ[@YZ[G�f3��N8jO@ONPGOV[I�\�IFNPNM@�]FGOVKVKIF?hZKI�I_V[G6Uc@YZa@�\�EPW8IF?�\�IbVY`@�\-@ONHNH@XZKVa@O?�JK]v@=�Va@YZKZKIbV[EHJ�Z[EH]v@y\�IFN \�EHJLW8G6JKEPZKEPjcG�IX\-@ON®jO@ONPGOV[I�\�IFNHNH@�V[IFJLEHJLZ[Ib?�Dv@e\�E¡JKG6BV[]FIYf

/7/

Page 26: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

z�IbVuNM@QW7G6NM@YVKEHDFDv@ODbEHG6?�I�\�IFE�ZKVa@O?�JKEPJLZ[GOV[EÁ�U ¬ JKE�V[EH]FGOVLV[Ie@%JK]ar�IFRTEd\�E{@O?-@ONHG6Uc@QJKIFReW-NPEH]FE^ZY`@f½ G6?�JKEH\�IbVKEM@ORTG�W7IbV�IFJKIbReW-EHG�EHN�]v@OJLGX\�E-B�?gZKV[@O?�JKEHJLZKGOV[I(�U ¬ @�]v@O?-@ONHI�Îk@O\e@YVKV[EP]F]ar�EHRTIF?cZ[G�f

��N�W�@YVKZKEPZ[GOV[IeACGOV[Rt@YZ[Go\-@1¦ ¤ It¦u g]FG6?�JKIb?hZ[I%\�E�@YW�W-NPEH]v@YVKIQ@ONsUc@YZ[IT\�IbNsZKVa@O?�JKEPJLZ[GOV[I �Æ ¬B�?-@1Z[IF?�JKEPG6?�Ikº,É�É W�@YV[E5@�ºKú�¦u F­��:¦ ¤ *Цu  � fSz�G6EP]}rswIlº,Éq§ ¥ ºKÉ�É ¨ À��¦u§ m{@/j�V[IFRTGNp��I n B-@ODbEHG6?�I

À� ¥²¨ ´¦u§ º,Éq§ * ºKÉ�É

¦X§ -]ar�I�Va@YW�W�V[IFJKIb?hZa@yB�?-@�V[IbZKZ[@yJLB�N8W-EM@O?�Gy\�IFNPNM@XZKVa@O?�JL]v@YVa@YZKZ[I_V[EHJLZKEH]v@�\�E7B�JL]FEPZa@fd�{��EP?hZ[I_V[JKIFDFEPG6?�IZKVa@yZa@ONHI�V[IbZLZa@�IuNM@�ZKVa@O?�JK]F@YVa@YZKZ[IbVKEHJLZ[EP]v@gEP?�\�EPj)EH\�B�IbVY`@�EHN®W-B�?cZ[GT\�E®V[EPW8G6JKGe]bIbV[]v@YZ[G�f

`· ]ar�EM@YV[Go]ar�IOmq@ONHRTIb?�Gl\-@ONdW-B�?hZKGo\�E�jEHJ�Za@l\�IFNdACB�?�DFEPG6?-@ORTIF?cZ[GoEP?�]FG6?cZ[EH?hB-@mqJKE�W-Bq`GoA;@YVKI@eRTIb?�GTJKIF?�Dv@TW�V[GO�-NPIFRTE¡\�IFNPNM@gV[IbJKEHJLZKIF?�Dv@t\�E'JLG6BV[]FI�¦u§¡m�\-@YZ[GT]ar�I�NH@gZ[IF?�JKEPG6?�IyºKÉ'§�\�I_jcI]FG6RyB�? n B�IeIFJKJKIbVKIQW8G6JKEPZKEPjY@lW7IbV n B�IFJLZKGoZ[EPW8Go\�Es\�EPJLW7G6JKE^Z[EPjcGkIt?�G6?xIFJKEHJ�Z[G6?�GoW�V[GO�-NHIbRTE�\�EJLZa@Y�-EPNHEPDFDv@ODFEPG6?�I�Z[I_V[RTEH]F@f

/�F

Page 27: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

3 �5476� Sù ���5 ��Û²³�3 ���� �L�� ��q�{8�>ù�ù¡����� ´��q ´���°#°®�5�L�T�)�985 ����L�: �"!�þ©.¡0q$)9"9;.x9:2"&'$)*-(Y2;ÈcÈc*-,/.iÄ�$�(T,/(=*�&3üv2:üb,/.�(Y2sÊ�ˡ̽ G6RTIy?�IFNd]v@OJKGkU6EÇ`@Qj)EHJLZKG%W8IbVXEPN�\�EHG�\�G�m�`I�W7G6JLJKEP�-EPNHI�JLjEPNHBW�W�@YV[I�B�?�RTG�\�IFNHNPG%NPEH?�Iv@YVKEHDFDv@YZKG@O?�]ar�I�W8IbV�E3]FG6RgW7G6?�IF?cZ[E�@YZKZKEPjE'IOm®EH?1W�@YVKZKEH]FG6NH@YV[IOm®@O?�]ar�IyW7IbV�EqZLVa@O?�JKEHJ�Z[GOV[E���� � f£D�B�IbJLZ[GRTG�\�IFNHNPGS`I�jO@ONPEH\�GtJKG6N^Za@O?hZKGTW7IbV�W-EH]b]FG6NHE'JLW7G6JLZ[@ORTIF?cZ[E3EH?cZ[GOV[?�G%@ON W-B�?hZ[G%\�E3NH@/jcGOV[G�m�Za@ONHE'\-@W7GOZKIbV�@YW�W�V[G6JKJLEHRt@YV[I�EPN']bG6ReW7GOVKZ[@ORTIF?cZ[GT\�IFNqZLVa@O?�JKEHJ�Z[GOV[I�]FG6?�JLEH\�IbVa@O?�\�G%EqJLG6NHE'ZKIbV[RTEP?�E'\�IFNW�V[EPRTGXGOV[\�EP?�I¯\�IFNPNHG�J�jEHNPBW�W7GuEH?TJKI_V[EHIy�:?�IFN-]v@OJKG�\�IFN�ZKVa@O?�JKEPJLZ[GOV[I�JKE-ZKVa@YZKZ[@m�@u\�EP¶7I_V[IF?�Dv@�\�IFN\�EHG�\�G�m-\�IFNHNPGeJLj)EHNHBW�W8GeEP?kJKIbVKEHIX\�E¡ACB�?�DFEPG6?�E'\�E®W-EK`BkjO@YVKEM@Y�-EHNPE � f

��N�ZLVa@O?�JKEHJ�Z[GOV[I�`I�B�? n B-@O\VKEPW7G6NPG�m n B�EP?�\�E)EPN)JKB�G�RTG�\�IFNHNPG¯NHEP?�Iv@YV[EPDFDv@YZ[G�\�G/j)VY`@�IbJKJKIbV[I5Va@YW�W�V[IFJLIF?hZ[@Y�-EHNHIX]FG6?kB�? n B-@O\V[EPW8G6NHGgNHEH?�IF@YV[IOfd��N¡]FG6RgW7GOVKZa@OReIF?hZKG�IbNHIbZKZLV[EH]FGg\�E¡B�? n B-@O\V[E^W7G6NPGNHEP?�Iv@YV[I�W-Bq`G�IFJKJKIbVKIu]FG6RgW-NHIbZa@OReIF?hZKI�\�Ib�-?�EPZKG�ZKV[@ORTEPZ[I¯NHI�V[IFNH@ODFEHG6?�E7ZLVa@ n B-@YZKZKVKG�UOVa@O?�\�IFDFDFIY¢£K¤ m-� ¤ m £  Ym-�O Ym�NPI n B-@ONHE®JKG6?�GgJK]FIFN^Z[IX]bG6?oE®jcIbV[JKE¡EHNPNHB�JLZLVa@YZ[E®?�IFNPNM@��-U6BV[@gJKIFU6B�Ib?hZ[IY¢

;<�=> = > ;+

+

<

·s]b]FIbZKZ[G�]ar�I5EP?�]F@OJKE�W�@YVKZKEH]FG6NH@YV[Epm)`I5\�E)JKG6NPEPZ[G¯W8G6JKJKE^�-EHNHIsIFJLW�V[EPRTIbV[I5\�B�I�@�JK]bIFNPZa@�\�IbNHNHI n B-@YZKZKVKGUOVa@O?�\�IFDbDFI�EH?yACB�?�DFEHG6?�I�\�IFNPNHI5\�B�I�V[EPRt@O?�IF?cZ[Epfq�'I�V[IbNM@ODFEPG6?�E�ZKVa@¯Z[@ONHE)UOV[@O?�\�IFDFDFI5V[EPJKB�NPZ[I_Va@O?�?�G@O?�]ar®��IFJLJKITNHEP?�Iv@YV[E"f ¬ ]FIbU6NHEM@OReGl\�EdIFJLW�VKEHRTIbVKIg� ¤ I £  �EH?iACB�?�DFEHG6?�Ie\�E £L¤ Ig�O k� n B�IFJLZa@~`IgNH@JK]FIbNPZa@y\�E7JKG6NPEPZ[GyA;@YZKZa@�W8IbV�NM@�Va@YW�W�V[IFJLIF?hZ[@ODFEHG6?�I�NHEP?�Iv@YV[EHDbDv@YZa@�\�IFE7ZKVa@O?�JLEHJLZ[GOVKE � fúÂ�ZKZ[IbVLV[IFRTG�¢

? � ¤5¥ P ¤[¤[£L¤ * P ¤  b�6 £   ¥ P-  ¤[£L¤ * P� [ b�6 Y«

�sW�@YV[@ORTIbZKV[E#PA@�Bu]ar�I�\�I_�-?�EHJK]FG6?�G n B�IFJLZKGgRTG�\�IFNHNPG�JKG6?�G�\�IbZKZ[E8W�@YV[@ORTIbZKV[E8EP��V[EP\�Ed�:W7I_V[]ar�wIuNPIUOVa@O?�\�IFDbDFI�EH?�\�E^W7IF?�\�IF?cZ[E3JLG6?�GT\�E'Z[E^W7G�ZKVa@eNPGOV[GT\�EPjcI_V[JKG�¢�B�?-@eZ[Ib?�JKEHG6?�I�IXB�?-@T]FGOVKV[IF?cZ[I � IJKE¡EH?�\�EP]v@O?�GT]FG6?lNM@�NHIbZKZKIbVa@ÀP%\-@��LrïY���V[EH\���f

·�J[@ORTEH?�EH@ORTGQEH?i\�IbZKZa@OU6NPEHG%]FEM@OJK]bB�?�Go\�IFE�W�@YVa@ORTIbZLV[E³P7m EH?�\�E^jEP\�B-@O?�\�GoNHIyV[IFNH@YZ[EPjcIy\�E^�RTIF?�JLEHG6?�Ep¢ P ¤[¤�¥ P#CÕ�"EP?W-BZ �{¥ � ¤

£L¤EDDDDGF�H!IKJ LGMENP ¤   ¥ P#OF�;V[IbjcIbV[JLI ��¥ � ¤�6  DDDD @QP IRJ

Va@YW�W8GOVKZ[G @O\�EHReIF?�JKEHG6?-@ONPI

P-  ¤�¥ P2Sb�"ACGOV)õ�@YV[\ �{¥ £  £K¤TDDDDGF�HUIRJ

Va@YW�W8GOVKZ[G @O\�EHReIF?�JKEHG6?-@ONPI

P- [  ¥ P#Vh�"G6BZKW-BZ �{¥ £  �O  DDDD @QP IKJ LGM

< ¤N�'@y?�GOZ[@ODFEHG6?�I�]bG6?%W8IF\�EH]FE8NHIbZKZKIbVa@ONHE�EH?�\�EP]v@�Np��Ib¶7IbZLZ[G�]FG6?�?�IFJKJLGe@�]FEH@OJK]FB�?�Gy\�IFE8W�@YVa@OReIbZKV[E P7¢P#@5IFJLW�V[EPRTIyEHNqVa@YW�W8GOVKZ[GtZKVa@tNH@QZ[Ib?�JKEHG6?�IyIyNM@t]FGOVKVKIF?hZKIgEP?iEP?�UOV[IFJKJKG�m n B�EH?�\�E�B�?-@ n B-@O?cZ[EPZ=`@

V[IFNH@YZ[EPjY@�@ONPNM@~JKG6NH@�Rt@OU6NHEH@i\�E�EH?�UOV[IFJLJKG�ÖBP#W1EH?�\�EH]F@�Np�¸@ODbEHG6?�Io\�IFNPNM@~Z[Ib?�JKEHG6?�Io\�E¯B�JK]FEPZ[@�JKBn B�IbNHNM@l\�EsEH?�UOVKIFJKJKG�m n B�EH?�\�EsB�?xI_¶7IbZKZKG1\�E�Z[E^W7GoEP?hjcIbVKJKG�ÖçP,VlVa@YW�W�V[IFJKIb?hZa@1EPN{Va@YW�W8GOVKZ[GoZKV[@NM@%]FGOVKV[Ib?hZ[Ie?�IFNHNH@lRt@OU6NPEM@Q\�E{B�JL]FEPZa@lI n B�IbNHNM@%?�IFNHNH@kRt@OU6NPEM@t\�E�EP?�UOV[IFJKJLG�mq\�B�? n B�IeNp��I_¶7IbZKZKG/7X

Page 28: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

\�EPVKIbZKZ[G�Is\�IFJKEH\�I_Va@YZ[G�Ö�P æ EH?�-?�I5IFJLW�VKEHRTI�EPNhV[@YW�W7GOVKZ[G�ZKVa@¯NH@¯]FGOVKV[Ib?hZ[I5IsNM@�Z[Ib?�JKEHG6?�I5\�EhB�JK]FE^Za@IF\i`I n B�EP?�\�E8V[IFNH@YZ[EPjcGy@ONPNM@�JKG6NH@�Rt@OU6NHEH@u\�E7B�JL]FEPZa@f{Ø�E8JKG6NPEPZ[G�j)EHIF?�I�W�VKIFJKGyEH?Q]FG6?�JKEP\�IbVa@ODFEPG6?�IEHN n B-@O\V[E^W7G6NPG%]bGOVKV[EHJ�W7G6?�\�IF?cZ[Ig@ONqRTG6?cZa@OU6U6EHGe\�IFN3ZKVa@O?�JKEPJLZ[GOV[Iy@tIFReIbZKZ[E^Z[GOV[I�]FG6RyB�?�IOm7jY@ONHI@o\�EPVKIt]FG6?�Np��IbRTIbZKZ[E^Z[GOV[Ig@1]FG6RyB�?�IeZKVa@1Np��EH?�UOV[IbJKJKG1ItNp��B�JK]FE^Za@fl��? n B�IFJ�Za@o]FG6?�-U6BVa@ODFEPG6?�I� ¤¯¥ �YXdW/m7�6  ¥ º[Z>W/m £K¤¯¥©£ X�I £   ¥ £ Z/f�z�IbV�J�W7IF]FE^�-]v@YV[Iy]ar�IyEqW�@YVa@ORTIbZLV[EúPoJKEqV[EPACIbV[EHJL]FG6?�G@ON¡RTG6?cZa@OU6U6EHG�@gIbRTIbZKZ[E^Z[GOV[I�]FG6RyB�?�I�JKEq@OU6U6EPB�?�U6IuB�?kJKIF]FG6?�\�GeW8IF\�EH]bIÑ�6¢

? �YXdW ¥ PA@tW £ X�* PAW%Wa�YZ>W£ Z ¥ PKV�W £ X�* P æ W_�YZ>Wv«

z�G6EH]arswIiNHI1V[IFNH@ODFEHG6?�E�@YW�W7Ib?-@�jEPJLZ[I�\�Ib�-?�EHJL]FG6?�G|B�? n B-@O\V[EPW8G6NHG�NHEH?�IF@YV[IOm¯W8G6JKJKEM@OReG�Va@YW�W�V[IFJLIF?hZ[@YV[I~Za@ONPI n B-@O\V[EPW8G6NHGÓ]bG6? B�?ÿ]FEPVK]FB�EPZ[G�I n B�E^jO@ONPIF?cZ[IOm�]FIbV[]F@O?�\�G�\�E�EP\�IF?cZ[EP�-]v@YVKI�EHNJKEPU6?�EP�-]v@YZ[G��-JKEH]bGT\�IFE®W�@YVa@ORTIbZLV[E®EP��V[EP\�Ep¢

1/

ie\be ]

re

]fe

\ce

^b

^b

^c

oe

]]

ò�EH?�GQ@gGOVa@T@Y���-EM@OReGeVa@YW�W�V[IFJLIF?hZ[@YZ[GQE W�@YVa@OReIbZKV[E¡EP��VKEH\�Eq]bG6RTIuVa@YW�W8GOVKZ[E¡ZKVa@eNPI�UOVa@O?�\�IFDbDFI\�EH?-@OReEH]ar�IOm5jO@ONPIS@�\�EPV[I1]bG6RTIkVa@YW�W8GOVKZ[E�ZLVa@�W-EH]F]FG6NPIojO@YVKEM@ODFEPG6?�E�\�IFNPNHI1UOVa@O?�\�IbDFDFI1Z[GOZa@ONPEpfz�G6JKJKEH@ORTG n B�EP?�\�E�@O?�]ar�ISEH?�\�EH]F@YV[NHE�I1]F@ONH]FG6NH@YV[NHE�]FG6RTI1NHEPRTEPZKIk\�IFE¯V[@YW�W7GOVKZ[E¯EH?�]bV[IbRTIF?cZa@ONHE\�IFNPNHI~UOV[@O?�\�IFDFDFI�Z[GOZ[@ONHE�IOm�\�E�]FG6?�JKIFU6B�IF?�DF@mu]FG6ReI~\�IbV[E^jO@YZKIiW�@YV[DFEH@ONHE�\�E�Za@ONHE�UOVa@O?�\�IFDbDFI�"?�IFNPNHI�I n B-@ODFEHG6?�E8]}r�I�JKIbU6B�G6?�G�B�JLIbV[IFRTG�m�W7IbV�]FG6?�ACGOV[ReEPZY`@�]FG6?QN"��B�JKGy]FG6RyB�?�IOmNH@�?�GOZa@ODFEPG6?�I]FG6?QJKEPRy�8G6NHGuI�W7IF\�EP]FI�Rt@OEHB�JL]FG6NHGXW8IbV5EP?�\�EH]v@YV[I�NPI�UOVa@O?�\�IFDbDFI�Z[GOZa@ONHE"m)@O?�]ar�I�JKI�JK@YV[Ib���7I�W-EK`B]FGOVKVKIbZKZ[GlEH?�\�EH]F@YV[NHI�]FG6?~JLEHR��7G6NPGlRTEP?�B�JL]FG6NHG%I�W8IF\�EH]bIeRt@OEPB�JK]FG6NHG�m¡]FG6ReI�JLE{A;@%EH?iU6IF?�IbVa@ONPI?�IFNPNp�¸@O?-@ONPEHJKE®\�IbE']FE^V[]FB�E^Z[E � fdz�IbV¯IFJKIFRgW-EHG�mW7G6JLJKEM@ORTG�JK]bVKEPjcIbV[IíPKV�W�]FG6RTIO¢

P,V�W ¥ NPEHR_U` �[a Jcb À��bÀ? DDDD�d $&� IRd $��2e ¥ f À�f À�? DDDDgd $�� Ihd $��2e -\�G/jcI�NH@u\�IbV[E^jO@YZ[@�W�@YV[DbEM@ONHI�jEPIF?�I�jO@ONPBZa@YZa@�W7IbV5ºK����]FG6JLZa@O?cZ[I�I�W�@YVKE�@ONjY@ONHGOVKI�?�IFN�W-B�?cZ[GX\�E

V[E^W7G6JKG�m]ar�I�]FGOVKV[EPJLW7G6?�\�Iu@O\%@OJKJKB�RTI_V[I�B�?-@�jY@YV[EM@ODFEPG6?�I�?�B�NPNM@�V[EHJ�W7IbZKZKGg@ON�W-B�?hZ[G�\�E7V[E^W7G6JKG�mI n B�EH?�\�E B�?-@g�iZ>W�?hB�NHNH@f

¼�IF\�EM@OReG�GOVa@�]FG6RTI�JKE8\�IbZ[IbV[ReEH?-@O?�GyE8W�@YVa@ORTI_ZKV[E8E^��V[EH\�E7@yIbRTIbZKZ[E^Z[GOV[I�]bG6R�B�?�I�@�W�@YVL�Z[E^V[I5\-@ONHNPI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I5\�IFN)ZLVa@O?�JKEHJ�Z[GOV[IOm6A;@O]FIb?�\�GuV[EPACIbV[EHReIF?hZKG�mYW7IbVdJLIFReW-NHEP]FEPZ=`@m6@ON)]v@OJLG�\�EB�?SZKVa@O?�JKEPJLZ[GOV[I���z���f ½ G6?�JKEH\�I_V[EM@ORTGt\-@YW�W�VKEHRt@tB�?-@TW�V[G)]bIF\�BVa@QIFJK]FNPB�JKEPjY@ORTIF?cZ[IyUOVa@Y�-]v@m��@OJ[@YZa@�JKB�NHNPIX]v@YV[@YZKZ[IbV[EPJLZ[EP]}r�I�\�E¡EH?�UOV[IbJKJKGTI�\�E'B�JL]FEPZa@fØ�@ONHNH@�\�Ib�-?�EPDFEHG6?�IYm#P#@zW�W-Bq`GTIFJKJLIbV[I�@YW�W�VKG6JKJKEHRT@YZ[Gg]bG6?oEHN®Va@YW�W8GOVKZ[GyZKVa@gNH@�jY@YV[EM@ODbEHG6?�I�\�IFNHNH@ºK?��ÐI n B�IFNPNM@t\�IFNPNM@tÀ�?¯m7W8IbVXºK���¿]FG6JLZ[@O?hZ[IyI�W�@YV[Ed@ONqjY@ONHGOVKI�\�EqV[EPW8G6JKG�f ¬ EqZKVa@YZKZ[@ n B�EH?�\�E\�EsW�V[Ib?�\�IbV[IQEH?�]FG6?�JKEP\�IbVa@ODFEPG6?�IQNM@o]v@YVa@YZLZ[IbV[EPJLZ[EH]F@o\�EsEH?�UOVKIFJKJKG�@1IFRTIbZLZ[EPZ[GOVKIe]FG6RyB�?�ITW7I_VºK��� ¥ ºK����þ�I�RTEHJKBV[@YV[I�NH@�W8IF?�\�IF?�Dv@�\�IFNPNM@�Z[@O?�U6IF?hZKI�?�IFNcW-B�?hZ[G¯]FGOVKV[EPJLW7G6?�\�IF?cZ[I5@�ºK?���þ¯f�{��EH?cjcIbV[JLGT\�E®Za@ONHI�Za@O?�U6IF?cZ[I�]FGOVKV[EPJLW7G6?�\�IXW�VKGOW�V[EHGe@ÀP#@zW+f

/ 6

Page 29: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

j

klQmonqp lrmKn

mk lts n lts nup

mup

Ø�@ONHNH@y\�I_�-?�EHDFEPG6?�IOm#P#W%W�W-Bq`GgIFJKJKIbVKI�@YW�W�V[G6JKJLEHRt@YZ[Gy]FG6?lEHN8V[@YW�W7GOVKZ[GyZKVa@yNM@�jY@YV[EM@ODFEPG6?�I�\�IFNHNH@ºK?��ÐI n B�IFNPNM@t\�IFNPNM@%ºK����m7W8IbV�À�?Ð]FG6JLZ[@O?hZ[IyI�W�@YV[Ed@ONqjY@ONHGOVKI�\�EqV[EPW8G6JKG�f ¬ EqZKVa@YZKZ[@ n B�EH?�\�E\�E¯W�V[Ib?�\�IbV[ISEH?�]FG6?�JKEP\�IbVa@ODFEPG6?�ISNHI1]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�Io\�E¯EH?�UOV[IFJLJKG�@�IbRTIbZKZ[E^Z[GOV[Il]FG6RyB�?�I1IjY@ONHBZa@YV[I�NH@g\�EP¶8IbV[IF?�DF@gZKVa@yNHIuºK?���]}r�IuJKE¡GOZKZ[IF?�U6G6?�G�JKG6RTRT@O?�\�G�GgJKGOZKZKV[@OIF?�\�G

bºK���s­ Ô @

ºK����þ�fd��N®Va@YW�W8GOVKZ[GyZKVa@yZa@ONHI�jO@YVKEM@ODFEPG6?�IbºK?���I n B�IFNPNM@y\�IFNHNH@�Z[Ib?�JKEHG6?�Iu\�E B�JL]FEPZa@

bº,���|]FE

ACGOV[?�EPJK]FIXEPN®jO@ONPGOV[Iu\�E P#W%W+fδ

vwrxKy

xv z|{~}�z�{~}~��z|����z������ z����� �� � ��� � ����� � ���� ��

wrxKyδ

δ

xu�

��NqW�@YVa@ORTI_ZKV[G3P,V�WuW-Bq`G%IFJKJKI_V[Ie@YW�W�VKG6JKJKEHRT@YZ[Gt]FG6?�EHNqVa@YW�W8GOVKZ[GtZKVa@tNH@tjY@YV[EH@ODFEHG6?�I�\�IFNPNM@QÀ��I n B�IbNHNM@�\�IbNHNM@xÀ�?�m�W8IbVlºK��� ]FG6J�Za@O?hZKI1IoW�@YV[E�@ON�jY@ONHGOVKI1\�E¯V[EPW8G6JKG�fÿØ�GO���-EM@ORTG n B�EH?�\�EW�V[IF?�\�I_V[I�EH?t]FG6?�JLEH\�IbVa@ODbEHG6?�I�NPI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I¯\�E�B�JK]FE^Za@�@XIFReIbZKZ[E^Z[GOV[I�]FG6RyB�?�I�I¯jY@ONHBZa@YV[INM@�\�EP¶7I_V[IF?�Dv@�ZKVa@�NHIsÀ�S]ar�I5JKEhGOZKZ[Ib?�U6G6?�G�JKG6RTRt@O?�\�G�G�JKGOZKZKV[@OIF?�\�G

bÀ?~@¯À�?�þ¯fq��NcVa@YW�W7GOVKZKG

ZKVa@eZ[@ONHIXjY@YV[EM@ODbEHG6?�I

bÀ�<I n B�IFNHNH@T\�IFNHNH@Q]bGOVKV[IF?cZ[Iy\�EqEP?�UOV[IFJKJKG

bÀ�? ]FEqACGOVK?�EHJK]FIyEPN'jY@ONHGOV[I�\�EP,V�W/f

δ

���

��

�G�'� ���'�'��

��� ����� ¢¡  £¡ �  �   ���   ��r�

�r¤ ¥ ¦§�¥ ¨©

δδ

δ

ª��?�-?�I¯EPN)W�@YVa@ORTIbZLV[GÑP æ WsW-Bq`GuIFJKJKIbVKI�@YW�W�V[G6JKJLEHRt@YZ[G�]FG6?�EHNV[@YW�W7GOVKZ[G�ZKVa@�NM@�jY@YV[EM@ODFEPG6?�I�\�IFNHNH@/ 4

Page 30: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

À��ÐI n B�IFNHNH@Q\�IbNHNM@%º,����m7W7IbV�À�?ÿ]FG6JLZ[@O?hZ[IyI�W�@YV[Ed@ONqjY@ONHGOVKI�\�E3V[EPW8G6JKG�fXØ�GO���-EM@OReG n B�EH?�\�EW�V[IF?�\�I_V[I�EH?t]FG6?�JLEH\�IbVa@ODbEHG6?�I�NPI�]v@YVa@YZKZKIbV[EHJ�Z[EH]ar�I¯\�E�B�JK]FE^Za@�@XIFReIbZKZ[E^Z[GOV[I�]FG6RyB�?�I�I¯jY@ONHBZa@YV[INM@QW7IF?�\�Ib?�Dv@k\�IFNPNM@%Z[@O?�U6IF?hZKIT@ONHNH@%]F@YVa@YZKZ[IbVKEHJLZ[EP]v@tW7IbVXÀ�? ¥ À?�þÿ?�IFNdW-B�?hZ[Gl\�E{VKEPW7G6JLG�fy��NjY@ONHGOV[IQ\�E(P æ WT]FGOVKV[EPJLW7G6?�\�I_VY`@SW�VKGOW�V[EHGi@SZ[@ONHITW7Ib?�\�IF?�Dv@fxØ�E5JKG6NHE^Z[GSNM@oZa@O?�U6IF?cZ[Ii`I n B-@OJKEGOV[EPDFDFG6?cZa@ONHIOm�\-@YZKG�EPN8W-EH]b]FG6NHGyjO@ONPGOV[I�\�E�P æ W=m n B�EH?�\�E®]FG6?cjEPIF?�Iu]bG6?�JKEH\�IbV[@YV[IuNH@�jO@YV[EH@ODFEHG6?�I�\�EÀ��|JKBkB�?oEH?cZ[IbVKjY@ONHNPGgReG6NPZ[Gg@OReW-EHG�m�W7IbV¯GOZKZ[IF?�IbVKIuB�?-@gW�VKIF]FEHJLEHG6?�I�@O]b]FIbZKZa@Y�-EPNHIOf

δ

«9¬

«­

®�¯�° ®g¯�°�±²

³Q´µ~¶ ³�´U±

· ¶¹¸ · ¶¹¸¹º ·�¶¹¸» ¼½ δ® ¶¹¸ ® ¶¹¸¹º ® ¶¹¸» ¾¿ δ

²

À��IFNPNM@gW�V[@YZ[EH]v@ÀP æ W�IâP,V�W�JKE jO@ONPBZa@O?�GTIb¶8IbZKZ[E^jO@ORTIb?hZ[I�]FG6?1NH@gW�V[G)]bIF\�BVa@ejEPJLZa@m PAW�W�JKEW7G6?�IX\�EqJKG6NPEPZ[G�W�@YV[Eq@TDbIbV[GtIâP#@zW�JKE'jY@ONHBZ[@eEH?cjcIF]FI�EP?oRTG�\�GT\�EPjcIbVKJKG�m�W8IbV[]arswI�NHIX]v@YVa@YZKZ[I_V[E^�

JLZ[EP]ar�IX\�E¡EH?�UOV[IbJKJKGTJKG6?�GgVa@YVa@ORTIF?cZ[I�\�EHJ�W7G6?�EP�-EPNHE"f��?�?-@O?�DFE^Z[BZKZ[G�\�GO���-EH@ORTGuW�VKIF]FEHJK@YV[I¯]ar�IBP#@zW�`I¯]FG6J�Z[EPZ[B�E^Za@u\-@u\�B�I¯]FG6ReW8G6?�IF?cZ[E�EP?eJKI_V[EHIOmÁ X'X�®I Á X�ÂZWvfd�q@�]bG6ReW7G6?�IF?cZ[I Á X'X�®]FGOVKVKEHJLW8G6?�\�I�@�B�?-@XV[IFJKEPJLZ[IF?�DF@yEP?�\�IFJKEP\�IbVa@YZa@m\�G/jBZ[@�@ONHNH@

W7GOVKDFEHG6?�IQ\�E���@OJKIQ]ar�I%jY@1\-@ON5]FG6?cZa@YZKZ[GS\�E5EH?�UOVKIFJKJKGi@ONHNH@SDbG6?-@i@YZKZKEPjY@��:��@OJKIQEH?cZKV[EP?�JKIF]v@ � f� @ONPIeV[IFJKEPJLZ[IF?�DF@1W�@YV[@OJKJKEPZ[@kW-Bq`Gi@vjcIbV[IgjO@ONPGOV[E�]bG6ReW�V[IFJKE{ZKVa@kW8G)]ar�E�G6r�R IeB�?�Ñ)EHNPG)G6r�Romq@JKIF]bG6?�\-@l\�IFNPNHI�]v@YVa@YZKZ[I_V[EHJLZKEH]ar�Iy]FG6JLZKV[BZLZ[EPjcI�\�IFN3ZKVa@O?�JLEHJLZ[GOVKIk�:\�E�JKG6NHE^Z[Gi`IyRTEP?�GOV[Iy?�IFE3ZKVa@O?)�JKEPJLZ[GOV[E�\�E�W8GOZ[IF?�Dv@1Rt@OU6U6EPGOV[I � f1�'@ Á X�ÂZWl`IQEP?hjcIF]bI%N"��Ib¶8IbZKZ[E^jO@oV[IbJKEHJLZKIF?�Dv@�@OJKJKG)]bEM@YZa@1]FG6?�EHNACB�?�DFEPG6?-@ORTIF?cZ[GT\�IFN®ZKVa@O?�JLEHJLZ[GOVKIOf�z�I_V¯]v@ONP]FG6NM@YVKI Á X�Â�W¯]FG6?�JKEP\�IbV[EM@OReGeB�?oRTG�\�IFNHNPG�W7IbV�NHI�jO@=�V[EH@ODFEHG6?�EW8IbVsEPN)ZKVa@O?�JLEHJLZ[GOVKI�EP?g]FB�E-EP?hZKVKG)\�B�]FEH@ORTG�B�?-@�V[IFJLEHJLZ[Ib?�Dv@X\�EP¶8IbV[IF?�DbEM@ONHI Á W�@�]FG6RyB�?�IZKVa@�NM@yRt@OU6NHEH@�\�E¡EP?�UOV[IFJKJKGgI n B�IFNHNH@g\�E¡B�JK]FE^Za@¢

Ãe

ÃÄbe

Åb

Åc

Åb

Æfe Ä

ce

bb’

� @ONPI�V[IFJKEPJLZ[IF?�Dv@%\�EP¶8IbV[IF?�DFEH@ONHIl`I n B�IFNPNM@t\�IFNHNH@%U6EPB�?�DFEHG6?�I���@OJKI}�ÕIFRTI_ZKZ[EPZKGOV[IOm¡]ar�I�W-Bq`G%IFJKJKI_V[IjY@ONHBZa@YZa@�@�W�@YVLZ[EPV[I�\-@ONHNPIuI n B-@ODFEPG6?�E \�E ·��8IbV[J����SG6NHNp¢

À� ¥ À��q§ÈÇ�� d ����É d � ¨ ´ËÊÌ*ÐÀ��'§K� d ���ÍÉ d � «F 2

Page 31: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

��N¯Z[IbVKRTEH?�IoV[IbNM@YZ[E^jcG�@ON¯U6IF?�IbVa@YZ[GOVKI�]bG6Rt@O?�\-@YZ[G�\-@ONHNH@�]FGOVKV[IF?cZ[I�?�IFN�\�EHG�\�G�\�E�]FG6NHNPIbZKZ[GOV[I?�G6?ÿ`I%JLZa@YZ[GiEH?�\�EH]F@YZ[G�\-@YZa@�NM@iW8G6NM@YV[EPDFDv@ODFEPG6?�IlEP?hjcIbVKJ[@�\�IFNHNH@iU6EPB�?�DFEHG6?�Il]FG6NHNPIbZKZ[GOV[I}�Ò��@OJKIOf¬ E�W-Bq`G�EH?�G6N^ZKV[IlZLVa@OJK]FBVa@YVKIkNp��B�?�EPZY`@SV[EHJ�W7IbZKZKGx@Æ� d ���ÍÉ d � m5\-@YZ[G~]ar�ISº,?���* º,[xI n B�EH?�\�E� d ���ÍÉ d �ÏÎ ´6f

z�G6JKJLEM@ORTG n B�EP?�\�E�GOZKZKIF?�IbV[IgEHN�V[IF]FE^W�V[G)]bGk\�E Á W�\�I_V[EPjY@O?�\�GoNM@%]FGOVKV[Ib?hZ[Ig\�E�IbRTIbZKZ[E^Z[GOV[IV[EPJLW7IbZLZ[GT@ONPNM@�Z[IF?�JKEPG6?�Iu��@OJKIuEH?cZKV[EH?�JLIF]v@=�ÕIbRTIbZKZ[E^Z[GOV[IO¢

´Á W ¥ f À�f º,?�� ¥ À���þº,È -\�G/jcIuÀ���þ `I�NM@y]FGOVKV[Ib?hZ[I�\�E®IFRTI_ZKZ[EPZKGOV[I�?�IFN7W-B�?cZ[Ge\�E®NH@/jcGOV[G�f���?�G6NPZLV[IOmW7G6EP]ar�wIuÀ���þ0*ÐÀ���þ�m

Á W ¥ º,ÈÀ���þ * º,È

À���þ «>�U6B-@OU6NHEH@ORTGTNH@Q�iXdWX?�IFN�]FE^V[]FB�EPZKGk@YW�W8IF?-@%IbJ[@ORTEH?-@YZKGl@ n B�IFNHNH@Q?�IbN�]FEPV[]bB�EPZ[G%I n B�E^jO@ONPIF?cZ[I�@W�@YVa@ORTI_ZKV[E®EP��VKEH\�Epm-JKIbReW-NHE^�-]v@YZ[GyZKVa@OJK]FBV[@O?�\�GëPAW�W�I P æ W=¢

\be ]

fe

\ce

^b

^b

^c

Ðbb’ Ð

b’e

z�IbV¯EHN®]FE^V[]FB�EPZKGe]FG6? Á W�@Y���-EH@ORTG�¢�YXdW ¥

LÁ X'X�Â�* Á W=�dP,V�W *д �

N£ X -RTIF?cZKV[I�W7I_V�EHN®]bEPV[]FB�E^Z[GT@yW�@YVa@ORTIbZLV[E®EP��V[EP\�E¡GOZKZ[IF?�EH@ORTG�¢

�YXdW ¥ � Á X'X�Â�* Á X�Â�W ��£ XF«Ø�@ON¡]FG6?�AMV[G6?cZ[GeZKVa@ n B�IFJ�Z[Iu\�B�IXI n B-@ODFEPG6?�E¡JKE®V[EH]v@vjY@g]ar�I

Á X�ÂZW ¥ Á W+�dPKV�W *д � * º"ÈÀ��þ �dP,V�W *д � * º,È

À���þ P,V�W/«�{��B�NPZKEHRt@QI n B-@ODbEHG6?�IT]FEdW7I_V[RTIbZKZKIg\�E�]v@ONH]FG6NH@YV[I Á X�ÂZWy@lW�@YVKZ[E^V[Ie\-@ONdjY@ONHGOV[Ig\�E{V[E^W7G6JKGk\�IFNHNH@]FGOVKVKIF?hZKIl\�E�]FG6NPNHIbZKZKGOV[ItIl\-@ n B�IFNPNHGS\�EÍPKV�W+f~z�IbVgZLV[G+jY@YV[I9P#@zWTJ[@YVY`@SJKBÙT]bEHIF?cZ[IkJLG6RTRt@YV[IÁ X�Â�W�I Á X'X�ÂÕm8JKBW�W8G6?�IF?�\�G n B�IFJLZv��B�NPZ[EPRt@e?�G6?S\�EPW8IF?�\�IF?cZ[Iy\-@ON'W-B�?cZ[GQ\�E'V[E^W7G6JKG�m8\-@YZ[Gt]ar�IQ`INHIbUc@YZa@�JLG6NPZa@O?cZ[GT@yW�@YVa@ORTIbZLV[E®]FG6JLZKVKBZKZ[EPj)E®\�IFN¡ZKVa@O?�JKEPJLZ[GOV[IOf

� @ON^jcG6NPZa@�EHN6U6Ib?�IbVa@YZ[GOV[I�\�Ec]FGOVKV[IF?cZ[I�]bG6Rt@O?�\-@YZ[G�EH?XB�JL]FEPZa@�jEHIb?�I{Va@YW�W�VKIFJKIF?cZa@YZ[G�m6EP?hjcIF]bI]ar�IQ]FG6RTITB�?�U6IF?�IbV[@YZ[GOV[IQ\�Es]FGOVLV[IF?cZ[IQ]FG6Rt@O?�\-@YZ[G1EP?x]FGOVKV[IF?cZ[IOm{]FG6RTIeB�?�U6Ib?�IbVa@YZ[GOV[It\�E]FGOVKVKIF?hZKIX]FG6Rt@O?�\-@YZKGgEP?kZ[IF?�JKEPG6?�IOm-JKIF]FG6?�\�GtNPGgJL]}r�IbRt@eJKGOZKZKGgVa@YW�W�V[IbJKIF?cZa@YZ[G�f

b’e Ñ Ò ce

m Ò b’e

Ób

Óc

Ôbb’ Ô

b’eÒ be Ò F ´

Page 32: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

�'@%Z[IF?�JLEHG6?�I�\�E{]bG6?hZKVKG6NHNHG�`I��YX�Â�W+m¡]FGOVKV[EPJLW7G6?�\�Ib?hZ[IT@ONHNM@t\�E^¶7IbV[Ib?�Dv@k\�E�W7GOZ[Ib?�DFEM@ONPI�W�V[IbJKIF?cZ[I@OEs]F@YW-E5\�IFNHNH@ Á X�ÂZW/f `·²JKIFReW-NPEH]FIt\�I_Z[IbV[RTEP?-@YV[ItNM@kVKIFNM@ODFEPG6?�ItZKVa@ë¸7º IQE�W�@YV[@ORTIbZKV[E{W�V[IF]FI}�\�IF?cZ[IFRTIb?hZ[I�]bG6?�JKEH\�IbV[@YZ[Epm�EHReW8G6?�IF?�\�GTNp��B�U6B-@OU6NHEH@O?�Dv@g\�IFNPNHI�]bGOVKV[IF?cZ[Eq\�E']FG6NHNPIbZKZ[GOVKIX?�IFE \�B�I]FE^V[]FB�EPZKEp¢ PKV�W £ X ¥ ¸7º��iX�ÂZW/«Ø�@YZ[G¯]ar�I��iX� W ¥ Á X�Â�W £ XFmYGOZKZ[IF?�EH@ORTG�]ar�IÛ¸�º ¥ P,V�W_­ Á X�ÂqW+fq��N6W�@YVa@ORTIbZLV[GŸ�º|r-@¯NHI�\�EHRTIb?�JKEHG6?�E\�IFNPNp��EP?hjcI_V[JKG�\�E�B�?-@�V[IFJLEHJLZ[Ib?�Dv@m n B�EH?�\�E

M< ¤ G ¬ �"JKEPIFRTIF?�J � f ¬ W7IFJLJKGXJKE�BZKEHNHEPDFDv@�]FG6RTI5B�?�E^ZY`@

\�E3RTEPJKBVa@TW7I_VQ¸�º Np�¸@ORgW7IbV[IXJKB�jcG6N^Zg�"¾¼»=¼ � GQEHNqRT¾¼»=¼ �"\�EPRTIF?�JKEPG6?-@ONHRTIF?cZ[I�I n B�EPjY@ONHIF?cZ[E@ONHN"��EP?hjcIbVKJKGe\�E¡B�?-@�VKIFJKEHJ�Z[IF?�Dv@ � f

: �;Â~þ©.¡0q$)9"9;.x9:2"&'$)*-(Y2;ÈcÈc*-,/.iÄ�$�(T,/(=*�&3üv2:üb,/.�(Y2s*~$21�$�,v,/.x032s4c*�É�Ä{.¬ E�BZ[EPNHEPDFDv@xNHG�JLZ[IbJKJKG�RTG)\�IFNPNHGxNPEH?�Iv@YV[EPDFDv@YZ[G�m�RTG6N^Z[G�JKIFRgW-NHEH]bIOm�W8IbVQZ[BZKZ[E¯E¯ZKVa@O?�JKEPJLZ[GOV[E�@Ib¶8IbZKZ[Gx\�E�]F@OReW7G<�"JLEM@¹�U ¬ ò�· � JKEH@x�7ò�· ��� fs·�JKJKG<`I1]FG6JLZ[E^Z[B�EPZKGx\-@�B�?<U6Ib?�IbVa@YZ[GOV[I1\�E]FGOVKVKIF?hZKIg]FG6RT@O?�\-@YZ[GlEP?�ZKIF?�JKEHG6?�IYm']FG6?iEH?�W�@YVa@ONHNPIFNHGQB�?-@%VKIFJKEHJ�Z[IF?�Dv@ ÁËÕ m¡]ar�IgVa@YW�W�VKIFJKIF?cZa@Np��Ib¶7I_ZKZ[Ge\�G/jBZKGT@ON®ACIF?�G6RTIb?�GT\�E @O]F]FGOV[]FEH@ORTIF?cZ[Ge\�IbN ]F@O?-@ONHI�@ON®]_V[IFJK]FI_V[I�\�EqºK�§ f

��NOjO@ONPGOV[I{\�IFNHNH@�ZKV[@O?�JK]FG6?�\�BZKZa@O?�DF@Ÿ7º �"\�IFNHN"��GOV[\�EP?�I�\�E n B-@ONH]ar�I�Re¾¼»=¼�W8IbV'NM@�Rt@OU6U6EHGOV®W�@YVKZKI\�IFE ZKVa@O?�JKEPJLZ[GOV[E'@TIb¶7I_ZKZ[GT\�E']v@OReW7G � JKE W-Bq`GTV[EH]v@vjY@YV[I�\-@ONHNH@gZKVa@O?�JL]v@YVa@YZKZ[I_V[EHJLZKEH]v@eACGOVK?�EPZa@eEP?ACGOV[Rt@�UOVa@Y�-]v@�\�IbZ[I_V[RTEH?-@O?�\�G�NH@�W7IF?�\�Ib?�Dv@�\�IbNHNM@¯Z[@O?�U6IF?hZKI�@ONHNM@�JLZ[IFJKJK@�?�IbN�W-B�?cZ[G�\�ENM@vjcGOV[G�m]ar�I5]FGOVKV[EPJLW7G6?�\�I�W�VKGOW�V[EHG�@(¸�º�f3JKI5NM@�]v@YVa@YZKZ[I_V[EHJLZKEH]v@X`IsEH?cjcIF]FI5ACGOV[?�E^Za@�EH?�Rt@O?�EPIbVa@�@O?-@ONPEPZ[EP]v@m¸7º JKE¡W-Bq`GeGOZKZ[Ib?�IbV[IX\�I_V[EPjY@O?�\�GTÀ�ÐV[EPJLW7I_ZKZ[GT@eºKÉ'§ f{z�IbV�B�?1�7ò�· � GOZKZ[IF?�EH@ORTG

¸7º ¥ ¨ Ô À��§)§ºKô �¡´ ¨ º,Éq§

ºKô ��«

D�B�IFJLZa@�ACGOV[RyB�NH@|`IljY@ONHEP\-@iW7IbVt�0ò�· � JKEM@�@i]v@O?-@ONHIgÍ�JKEM@�@i]v@O?-@ONHIoÎÐIk\q`@�NHB�G6U6G�@~B�?jY@ONHGOV[I%\�EÖ¸7º JKIbReW�V[IlW8G6JKEPZKEPjcG�f `· EHReW8GOVKZa@O?cZ[IQJKGOZKZ[G6NPEH?�Iv@YV[I%]ar�IoJKIlNM@i]F@YVa@YZKZ[IbVKEHJLZ[EP]v@�`IACGOV[?�E^Za@TEH?SRTG�\�GTUOVa@Y�-]FGS`I�GOW�W7GOVLZ[B�?�GQBZ[EHNPEHDFDv@YVKI�EHN'RTIbZ[G�\�Gt\�IFNHNH@eZa@O?�U6IF?cZ[I�W7IbV�VKEH]v@vjO@YVKI¸7º�mqEH?cjcIF]FIt\�E{\�IbZ[IbV[ReEH?-@YV[IQº,ôÿITÀ��§)§�W7IbV�W8G6E{W�VKG)]FIF\�I_V[It]FG6?xNp��IFJLW�V[IbJKJKEHG6?�IQ@O?-@ONPEPZ[EP]v@fD�B�IFJLZv��B�NPZ[EPRTGQRTIbZ[G�\�G�m®@OJKJ[@OE�JK]bG6?�JKEHU6NPEM@Y�-EHNPIOm7W-Bq`GlW8GOVKZa@YV[Iy@tV[EPJKB�NPZa@YZKE3JKEHU6?�E^�-]v@YZ[E^jO@ORTIb?hZ[I\�EPjcI_V[JKE-\-@ n B�IFNHNPGuUOVa@Y�-]bGuW7I_V[]ar�wI¯NM@�ZKVa@O?�JK]F@YVa@YZKZ[IbVKEHJLZ[EP]v@�?�G6?k`I�IFJ[@YZKZa@OReIF?hZKI�B�?-@�W�@YVa@Y�7G6NH@�"N"��IFJLW�VKIFJKJKEPG6?�I�@O?-@ONHE^Z[EH]F@l`I�JKG6NPZa@O?cZ[G�B�?®�¸@YW�W�V[G6JLJKEHRt@ODbEHG6?�I � f

��NjY@ONHGOV[I�\�IFNPNM@�V[IFJKEPJLZ[IF?�Dv@�\�EP¶8IbV[IF?�DFEH@ONHI ÁËÕ JKEV[EP]v@vjO@�@O?�\-@O?�\�G�@�jO@ONPBZa@YV[I�NM@�W7Ib?�\�IF?�Dv@\�IFNPNM@�Za@O?�U6IF?cZ[IX@ONPNHI�]v@YVa@YZLZ[IbV[EPJLZ[EH]ar�I�\�E®B�JK]FE^Za@gEP?l]bGOVKV[EHJ�W7G6?�\�IF?�Dv@g\�IFN7W-B�?hZKGe\�E®NM@vjcGOV[G�¢ ÁËÕ]FGOVKVKEHJLW8G6?�\�I�@ONHN"��EP?hjcIbVKJKGe\�IFN¡]FG�IbÙT]bEHIF?cZ[I�@O?�U6G6NH@YV[I�\�E¡Z[@ONHI�Za@O?�U6IF?cZ[IOf

z�IbV n B-@O?hZ[G�VKEHU6B-@YV[\-@�E)ZKV[@O?�JKEHJLZKGOV[E��U ¬ m6JKI�NM@¯ZKVa@O?�JL]v@YVa@YZKZ[I_V[EHJLZKEH]v@�`I5ACGOV[?�E^Za@�EH?yRTG)\�GUOVa@Y�-]FGxJLE�W�V[G�]FIF\�ISEH?�RTG�\�Gx@O?-@ONHG6U6G�@ n B-@O?cZ[GxU6E�`@ij)EHJLZKG�W7IbVtE¯�7ò�· � f ¬ IOm�EH?cjcIF]FIYm�NH@ZKVa@O?�JL]v@YVa@YZKZ[I_V[EHJLZKEH]v@l`Iu\-@YZa@�EH?lACGOV[Rt@e@O?-@ONPEPZ[EP]v@mNH@gJKE¡\�IbV[E^jO@�V[EHJLW8IbZKZ[Gg@Tº,Éq§¡m-GOZKZ[IF?�IF?�\�G

¸7º ¥ Ô Ê � ß à � �Òº,Éq§ ¨ º"È � «FcÔ

Page 33: £K¤ - unipi.itbrahms.iet.unipi.it/esd/sez2.pdf · JKGOZKZKG6JLZa@O?cZ[I m ]ar IOm{]FG6RTIejcIb\ V[IFRTG m \q` @1NHB G6U6G @ONPNp EP?hZKIbVa@ODFEPG6? IeZKVa@oNPIt\ B I%U6EPB ? DFEHG6?

�'@ ÁËÕ \�IFE�ZLVa@O?�JKEHJ�Z[GOV[EÅ�Æ ¬ JKE�V[EH]v@vjY@~]FG6RTIlU6E�`@ij)EHJLZ[G�W7IbVTE¯�7ò�· � JKIkNHIo]v@YV[@YZKZ[I_�V[EPJLZ[EH]ar�IT\�E�B�JK]FE^Za@oJKG6?�G1\�EHJ�W7G6?�EP�-EPNHE{EH?xACGOV[RT@lUOVa@Y�-]v@f ¬ ITJKG6?�G1EP?hjcIb]FIT\�EHJ�W7G6?�EP�-EPNHE�?�IFNHNH@ACGOV[Rt@�\�IFNHN"��IFJLW�VKIFJKJKEPG6?�I�ACIb?�G6RTIF?�G6NHG6U6EP]v@¯]ar�I�EH?�]FNPB�\�I5NM@�ZKIF?�JKEHG6?�I5\�E�·�@YV[N�YcmYJKE�GOZKZ[EPIF?�I�]FG6RTIEH?cjcIbV[JLGT\�IFNHNH@g\�IbVKEPjY@YZa@g\�E®Za@ONPIuIFJ�W�V[IFJKJKEPG6?�IXV[EPJLW7IbZLZ[GT@eºK�§ ¢

ÁËÕ ¥ �×Ö À�Ö ºK�§ � < ¤ ¥ ´³*áì8ºK�§ì�À «

¬ I ì�ºK�§Ø- ´6m�@Y���-EM@OReG ÁËÕ *©´+­��¡ì�À� � f

F6¹