Sensitività
1) relative Sensibility:
The sensibility is the coefficient of proportionality
between the variation 
of one characteristic
y(x) and the 
variation of an element, obtains from
the development in series of Taylor 
considering
the single linear term has in fact 
whose 1° member
goes divided for y(x0) and 2° the
member for x0 obtaining the
relative sensibility 
.
2) Property of the relative sensibility:
3) multiparametric Sensibility:
Esplica it the effects on the function of N(s) net of the
simultaneous variation of various parameters 
.
Analysis of the effects of the variations of the members and optimization
4) bilinear Theorem:
One whichever function of H net of a linear and permanent
circuit is esprimibile, in function of the stiffness of its bipolar
member, by means of the expression 
in which Z
it is the stiffness of the interest member, Zth is the stiffness that is obtained applying the
theorem of Thevenin to the heads of the interest member; H(0)
and H(¥) represents the values
that H assumes when the member is replaced respective from a short
circuit and an open circuit.
5) Expression of the sensibility by means of the bilinear theorem:
a great improvement in how much is obtained therefore is not necessary to carry out the calculation of the derivatives while H(¥) and H(0) they are in kind enough simple to calculate.
6) Calcolo of the multiparametric sensibility with the added net:
The bilinear theorem concurs to avoid the calculation of
the derivatives but it demands the analysis of the circuit for many
times how many are the present members, in order to obviate to that
has developed the method of the added net, considering the function of
transfer in tension of a circuit constituted from bipoles Zk , generators it controls and nullori and
applying to the theorem of Tellegen (for… two having
circuits the same one to you graph oriented the product to scale of
the carrier currents of one for the carrier tensions of the other
turns out null) obtains the 
relation that it must
be satisfied from the elements of the added net. It is obtained
che:
to) the bipole of income it is a short circuit
b) the bipole of escape is a generator of current with unitary current impressa
c) to every stiffness of the departure net corresponds the same stiffness in the added net
d) to every nullatore of the departure net a noratore in the added net is replaced and viceversa
and) to every generator of tension controlled in tension a generator of tension is replaced controlled in current
and therefore it is reached 
the
. Following sensibilità of the function of transfer to the
variation of the members of the circuit are obtained therefore:
, 
,
, 
.