13.19) An Introduction to reliability and maintainability engineering

The B. A. Tester Company provides a product-testing service specializing in small household appliances. A new product line of Major Electric toaster ovens is tested with the following results: Unit Time (operating hr.) Outcome # 1 380 failure #2 35 # 3 #3 65 failure inadvertently disconnected from test stand failure #4 220 # 5 28 failure #6 500 #7 # # 500 415 #8 #9 183 test terminated test terminated failure damaged by tester and removed test terminated an test terminated failure #10 500 #11 500 #12 110 (a) Based on the product limit estimator, is the manufacturer's claim that only 10 percent of the units will fail over the first 50 hr of use supported? (b) Based on the exponential distribution and using the maximum likelihood estimator, what is the reliability at 50 hr and a 90 percent design life? (c) Based on the Weibull distribution and using the maximum likelihood estimator, what is the reliability at 50 hr and a 90 percent design life? a The B. A. Tester Company provides a product-testing service specializing in small household appliances. A new product line of Major Electric toaster ovens is tested with the following results: Unit Time (operating hr.) Outcome # 1 380 failure #2 35 # 3 #3 65 failure inadvertently disconnected from test stand failure #4 220 # 5 28 failure #6 500 #7 # # 500 415 #8 #9 183 test terminated test terminated failure damaged by tester and removed test terminated an test terminated failure #10 500 #11 500 #12 110 (a) Based on the product limit estimator, is the manufacturer's claim that only 10 percent of the units will fail over the first 50 hr of use supported? (b) Based on the exponential distribution and using the maximum likelihood estimator, what is the reliability at 50 hr and a 90 percent design life? (c) Based on the Weibull distribution and using the maximum likelihood estimator, what is the reliability at 50 hr and a 90 percent design life? a