On Process Capability Analysis under Fuzzy Normal Distribution

Kaya I., Kahraman C.

3rd International Conference on Intelligent System and Knowledge Engineering, Xiamen, China, 17 - 19 November 2008, pp.424-428 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1109/iske.2008.4730967
  • City: Xiamen
  • Country: China
  • Page Numbers: pp.424-428
  • Istanbul Technical University Affiliated: Yes


Process capability indices (PCIs) are very useful statistics to summarize process' distribution and width. They are one of the results of process capability analysis. This analysis is based on normal distribution approximation which is used to calculate the probability of the process to produce between and out of specification limits. In this paper, process ability which is defined as produce conforming items is analyzed by taking fuzzy normal distribution into account. Mean, standard deviation and specification limits are defined as triangular and trapezoidal fuzzy numbers, respectively. Then fuzzy probabilities of conforming and nonconforming items are calculated.