TECH SPOT: SAMPLE CRE QUESTIONS (Part 2)
1. The predicted reliability is higher than the long term realized probability. Which of the following is the MOST likely cause of this difference ?
A. Deterioration of the manufacturing processes and procedures.
B. Lack of adequate employee training and process audits.
C. The accumulation of random process variations.
D. A poor initial estimation of reliability.
2. In a corrective action system, trend analysis can be defined as :
I. Long-term movement. III. A cyclical component of a time series.
II. The short term status of problems. IV.. Seasonal variations.
A. I only
B. II and III only
C. I, II and III only
D. I, II, III and IV
3. The MOST valid source of failure rate data is :
A. Test data obtained under very closely controlled conditions.
B. Environmental test data.
C. The manufacturing process.
D. Operational data.
4. A comprehensive failure analysis and corrective action feedback loop must determine :
I. What failed. II. How it failed. III. Why it failed.
A. I only
B. I and II only
C. II and III only
D. I, II and III
5. What is this system’s reliability at 700 hours?
Where component failure data is :
– Failure rate of A = 0.0007 failures/hr – Reliability of B = 0.92
– MTTF of C = 1400 hours – Reliability of D = 0.85.
6. Given mean-time-to-failure of 200 hours for each of two components, what is the probability of system failure if both components operate in parallel for one hour ?
A. P = 0.010
B. P = 0.005
C. P = 0.001
D. P = 0.000025
7. Reliability prediction is :
A. A one time estimation process.
B. A continuous process starting with paper predictions.
C. More important than reliability attained in the field.
D. A popular method as simulation theory.
8. Ideally for a FRACAS to be effective, how many failures should be allowed to pass before corrective action is to be undertaken ?
A. First occurrence of a failure mode.
B. Second occurrence of a failure mode.
C. Third occurrence of a failure mode.
D. Fourth occurrence of a failure mode.
9. All of the following Boolean algebra expression are incorrect EXCEPT ?
A. 1 + 1 = 2
B. 1 – 1 = 1
C. 1 – 0 = 0
D. 1 + 0 = 1
10. What is the MOST accurate method to verify that the maintainability requirement of a design is being met ?
A. By analysis of the design.
B. By performing maintainability prediction.
C. By thorough design reviews.
D. By demonstration at the customer’s facility.
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