Fuzzy logic approach in statistical process control and an application

On the study of Statistical Process Control (SPC), the control chart selection is important to control the quality characteristic. If the quality characteristic is uncertain, classical control chart will be inadequate to explain and evaluate the process quality. In this study, to establish the process control charts the use of fuzzy logic and to display fuzzy control charts with an application is aimed.In the first and second part of the study has included the theoretical information of SPC, fuzzy logic and fuzzy control charts; in the third part of the study has included of the application consisted of a textile company located in Denizli. Values were two-month observation has been taken from the company has recently began the work of SPC and analysis has been made based on these data. Plotting control charts and fuzzy control of classical control charts were made in two main categories. Because of appropriateness of the data set the u-control charts are used for drawing graphs of classical control. Fuzzy control charts, including the linguistic expressions of uncertainty motion fuzzy mode, fuzzy median, fuzzy midrange and a new approach to change in the range by Gülbay and Kahraman (2006) proposed by the "Direct Fuzzy Approach (DBY)" was applied. These approaches have been developed with ?-cut; fuzzy data in fuzzy environment, carried traits were assessed as not to lose.The results of the last parts of the study, a combination of graphics, whether drawn, comparisons were made. Comparisons of control points as a result of the u-control charts were greater than the statistics of fuzzy control. In addition, u-graphics decisions such that "under control" and "out of control", as an alternative "partially under control" and "partially out of control" can be given such decisions. Fuzzy control charts marked used in business decision making was weighted according to the desired the linguistic expressions, may have been provided flexibility in decision-making was required.