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ESTRO IMRT course 2015
IMRT optimization: algorithms&cost functions
Brussels October 5th, 2015
-49-
) (
Df
N
D
i
Dose in volume element
i
of an organ/tumour
Number of volume elements
number of
regret
assigned to the dose
D
in this volume
element
Purpose: to
quantify
our concept of
quality
of a dose distribution
By convention: if
D
1
is
better
than
D
2
, then
F(D
1
) < F(D
2
)
:
search the
minimum
of
F
.
Commonly, the cost function has the form:
∑
=
=
N
i
i
Df
N
F
1
) (
1
Properties of Cost Functions