Development of fuzzy supplier-rating by trapeze fuzzy membership functions with trigonometrical legs

In every fields of industry, suppliers create the elements for the final products of OEM (Original Equipment Manufacturer), which means, suppliers ”define” the quality of the final products via the quality of elements. Due to this, the continuous evaluation of supplier performance can be one of the most effcient risk assessment tools to identify weakness in early stages, make the possibility to implement corrective actions in time. The paper offers new development of supplier-rating based on fuzzy set theory where trapeze fuzzy membership functions are used with trigonometrical legs. This investigation is made for providing better rating by the authors. This interpretation is more effective and correct of course in point of view of manufacturing.