الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Problems or op~imal con~rol have received a grea~ deal or
aLLen~ion during ~he past decade owing to ~he increasing demand
for sy.Lens or high performance and to the ready availabili~y of
~e digital coaputer. The concept at control sy5Lem optimization
comprises a selection of a performance criterion and a design
which yields the optiaal con~ol sy5Lem within limi~ imposed by
physical constrain~. Such an optimal control sys~ea differs from
an ideal one in that the for.er is the best a~tainable in the
presence of physical cons~rain~s whereas the la~ter aay well be an
unatLainable goal. In solving proble.s or op~i.al con~rol sys~e.a,
~he goal is ~o find a rule tor de~erMinimc the presen~ control
decision, subjec~ to cerLain cons~rain~s which will minimize some
-asure ot a deviation from ideal behaviour. Such a •easure is
usually provided by a cri~erion or op~imization, or performance
index. The performance index is a runction whose value indicates
how well the actual perroraance or Lhe system ma~hes the desired
performance. In mos~ practical cases, sys~e• behavior is opti•ized
by choosing the control vec~r in such a way tba~ ~he performance
index is mini•ized (or maximized) £L,5,13,321.
Tbe perfor~~~ance index is import..ant becuase i~, ~o a large
degree, determines the na~ure or the resulting optimal con~rol.
That is, ~he resulting control may be linear, nonlinear,
sta~ionary or ~ime varying, depending on ~he tor• or
performance index. The control engineer formulates this index
based on the requirements or the proble•. Thus, he intluences the
nature of ~he resulting syste.. The requirements or the problem
usually include not only perrormnce requirements bu~ also
res~rictions on ~e form or ~he control to ensure physical
realizability. The optimization process should provide not only
control policies, parameter conricura~ions which are optimal, but
also a measure or the decradation in performance by ~he departure
at the perrormance index runc~ion tram its minimum Cor maximum>
value which results rrom the use of nonoptimal con~rol policies.