INDIAN INSTITUTE OF TECHNOLOGY ROORKEE

NAME OF DEPTT./CENTRE: Department of Electrical Engineering

1. Subject Code: EE-684 Course Title: System Reliability

2. Contact Hours: L: 3 T: 1 P: 0

3. Examination Duration (Hrs.): Theory: 3 Practical: 0

4. Relative Weight: CWS: 25 PRS: 0 MTE: 25 ETE: 50 PRE: 0

5. Credits: 4 6. Semester: Both 7. Subject Area: PEC

8. Pre-requisite: NIL

9. Objective: To introduce the concepts of reliability modeling of systems and their applications in

assessing the system adequacy in terms of relevant reliability indices.

10. Details of Course:

S. No. Contents Contact Hours1. Review of Probability Theory: Probability concepts, rules for

combining probability, probability distributions, random variables, density and distribution functions, mathematical expectations, variance and standard deviation.

3

2. Catastrophic failure models: Component reliability from test data, MTTF, time dependent hazard models, stress dependent hazard models, treatment of field data

5

3. Basic Reliability Evaluation: General reliability functions, probability distributions in reliability evaluation, and evaluation of series, parallel, series –parallel, and complex systems, event space method, cut-set method, tie-set method, and other methods, discrete Markov chains, continuous Markov process, frequency and duration technique concepts, standby and k out of n:G systems, application to multi-state problems, approximate system reliability evaluation, fault tree technique

12

4. Reliability enhancement: Component improvement, proper design and simplicity, creative design, conservative design and derating, redundancy and redundancy allocation

10

S. No. Contents Contact Hours

5. Drift failures: Concept of drift failures, failure mechanism, change in device and unit performance with time and loading/stresses, accelerated stress testing, creative design for drift failures.

5

6. System with repair: Availability, maintainability, MTBF, MTTR, UTR, k-out of n:G system with repair and installation, preventive maintenance.

7

Total 42

11. Suggested Books:

S. No. Name of Authors /Books / Publishers Year of Publication/

Reprint1. Shooman M.L., Probabilistic Reliability, an Engineering Approach, McGraw Hill 19682. Sinha S.K., Reliability and Life Testing, Wiley Eastern Limited 19863. Gupta A.K., Reliability, Maintenance and Safety Engineering, University Science

Press2009

4. Fuqua N.B., Reliability Engineering for Electronic Design, Marcel Dekker Inc. 1986