1.
Define TPM in your own words.
Technical performance parameters (TPMs) are the quantitative measures used to describe design-dependent parameters (DDPs). TPMs may be used to measure functional parameters, system reliability, system maintainability, usability, and system sustainability.
TPM’s allow designers to evaluate system performance and ensure the system meets the design requirements from the customer. 2.
Explain the differences between DDP and TPM.
Design-dependent parameters (DDPs) are design characteristics derived from performance and constraint parameters that are defined in system design models. Technical performance parameters (TPMs) provide a quantitative value for measuring these design characteristics, or DDP’s.
3.
A system has an MTBF of 2500 h. What is the probability that this system will survive 3000 hours without any failure if the failure is distributed exponentially?
P
(
t
)
=
e
−
t
/
MTBF
P
(
3000
)
=
e
−
3000
/
2500
P
(
3000
)
=
0.3012
The probability that the system will survive 3000 hours is 30.12%
4.
A system ABCD consists of four components, connected in a series structure. What is the probability that System ABCD will survive for 2500 hours without any failure if all the failures are distributed exponentially? R
ABCD
=
R
A
×R
B
×R
C
×R
D
=
(
0.0821
) (
0.2865
) (
0.2865
) (
0.3679
)
=
0.0025
The probability that system ABCD will survive for 2500 hours is 0.25%.
1.
Component A: MTBF = 1000 h
λ
=
1
MTBF
=
1
1000
=
0.001
R
=
e
−
λt
=
e
−
0.001
(
2500
)
=
0.0821
2.
Component B: MTBF = 2000 h
λ
=
1
MTBF
=
1
2000
=
0.0005
R
=
e
−
λt
=
e
−
0.0005
(
2500
)
=
0.2865
