Confidence Interval for Fuzzy Process Capability Index
نویسندگان
چکیده
Capability indices compare the actual performance of a manufacturing process to the desired performance. In practice these indices are estimated using sample data, often with quite small sample sizes. Thus, it is of interest to obtain confidence limits for actual capability index given a sample estimate. Most of the traditional methods for assessing the capability of manufacturing process are dealt with crisp quality. In this paper we obtain )% 1 ( 100 α − fuzzy confidence interval for p C ~ fuzzy process capability index, where instead of precise quality we have two membership functions for specification limits. A numerical example is given to clarify the method. Key-words:Fuzzy process capability index; Triangular fuzzy number; Ranking function; Fuzzy confidence interval. ∗ Corresponding author: Tel & Fax, 0098-341-3221080
منابع مشابه
A Consistent Confidence Interval for Fuzzy Capability Index
Fuzzy process capability indices are used to determine whether a production process is capable of producing items within specification tolerance, where instead of precise quality we have two membership functions for specification limits. In practice these indices are estimated using sample data and it is of interest to obtain confidence limits for fuzzy capability index given a sample estimate....
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