Burn-in is a method to improve the quantity of products.Burning-in a product means to subject it to a period of use prior to being used in field.Generally, burn-in is considered expensive and so the length of burn-in is typically limited.Thus,burn-in is most often accomplished in an accelerated environment in order to shorten the burn-in process.In this paper,the problem of determining optimal burn-in time is considered under the general failure model.There are two types of failure in the general failure model.One is Typeâ… failure.(minor failure)which can be removed by a minimal repair,the other is Typeâ…¡failure(catastrophic failure)which can be removed only by a complete repair.In the researches on optimal burn-in time,the assumption of a bathtub-shaped failure rate function is commonly adopted.In this paper, we assume that the failure rate function of products has a more general form, which includes the traditional bathtub-shaped failure rate function and the modified bathtub-shaped failure rate function as special Cases.Upper bounds. for optimal burn-in times are obtained in accelerated environment.Two numerical examples will also be given for illustration.
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