Detect Probable Malfunctions
Feature Description
What is the purpose of this algorithm?
The fault detection algorithm Detect Probable Malfunctions is similar to the algorithm Detect Malfunction with Fewest Tests. Both algorithms, for example, privilege tests that are more likely to detect a failure (in fact, the two algorithms use identical Test Weightings). The main difference is that the non-intrusive tests, although still performed before intrusive tests, are now split into two different Test Candidate Groupings. In this algorithm, non-intrusive tests that are located at internal output flags are performed before tests located at terminal output flags. Although diagnostics generated using this algorithm will tend to require more tests to detect a failure than those developed using the algorithm Detect Malfunction with Fewest Tests, the diagnostics for this algorithm will require less fault isolation (since better isolation is achieved during detection). Furthermore, this algorithm makes better use of all defined test points (the other algorithm will ignore tests defined at internal output flags when their functional coverage is also associated with tests defined at terminal output flags). For both algorithms, however, the prioritization of instrusive tests is the same.
How was this algorithm implemented?
The full set of test selection criteria for this algorithm are as follows:
1. Test Candidate Grouping 1 of 6: Non-Terminal BIT Tests
a) Candidate Test Types (3)
b) Weightings: uses algorithm defaults
c) Cutoffs: uses algorithm defaults
2. Test Candidate Grouping 2 of 6: Terminal BIT Tests
a) Candidate Test Types (3)
b) Weightings: uses algorithm defaults
c) Cutoffs: uses algorithm defaults
3. Test Candidate Grouping 3 of 6: Intrusive Tests
a) Candidate Test Types (2)
b) Weightings: uses algorithm defaults
c) Cutoffs: uses algorithm defaults
4. Test Candidate Grouping 4 of 6: Individual Net Functions
a) Candidate Test Types (1)
b) Weightings: uses algorithm defaults
c) Cutoffs: uses algorithm defaults
5. Test Candidate Grouping 5 of 6: Non-Terminal Output Flags
a) Candidate Test Types (1)
b) Weightings: uses algorithm defaults
c) Cutoffs: uses algorithm defaults
6. Test Candidate Grouping 6 of 6: Terminal Output Flags
a) Candidate Test Types (1)
b) Weightings: uses algorithm defaults
c) Cutoffs: uses algorithm defaults
1. Test Weighting 1 of 8: Sum Failure Probability
a) Priority: 80
b) Entity: Failure Probability
c) Type: Sum
d) Domain: Suspect Functions Detected
e) Best Equals: Highest
2. Test Weighting 2 of 8: Sum Failure Probability
a) Priority: 60
b) Entity: Failure Probability
c) Type: Sum
d) Domain: Suspect Failure Modes Detected
e) Best Equals: Highest
3. Test Weighting 3 of 8: Sum Failure Probability
a) Priority: 40
b) Entity: Failure Probability
c) Type: Sum
d) Domain: Suspect Functions Proven
e) Best Equals: Highest
4. Test Weighting 4 of 8: Sum Failure Probability
a) Priority: 30
b) Entity: Failure Probability
c) Type: Sum
d) Domain: Suspect Failure Modes Proven
e) Best Equals: Highest
5. Test Weighting 5 of 8: Count Number of Functions
a) Priority: 20
b) Entity: Number of Functions
c) Type: Count
d) Domain: Suspect Functions Detected
e) Best Equals: Highest
6. Test Weighting 6 of 8: Count Number of Failure Modes
a) Priority: 15
b) Entity: Number of Failure Modes
c) Type: Count
d) Domain: Suspect Failure Modes Detected
e) Best Equals: Highest
7. Test Weighting 7 of 8: Count Number of Functions
a) Priority: 10
b) Entity: Number of Functions
c) Type: Count
d) Domain: Suspect Functions Proven
e) Best Equals: Highest
8. Test Weighting 8 of 8: Count Number of Failure Modes
a) Priority: 5
b) Entity: Number of Failure Modes
c) Type: Count
d) Domain: Suspect Failure Modes Proven
e) Best Equals: Highest
C. Default Test Cutoffs (0)
