الفهرس 
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Abstract
Slub yarn characteristics were evaluated by a developed computer-based system to analyze the output signals of the measuring circuit of the Uster evenness tester. Results of the tested slub yarn samples showed that the actual slub geometrical parameters differ from the nominal values and the difference had two levels: prevailing difference and outlier values. The prevailing difference between the actual and nominal values was assessed and the results showed that the actual slub length always increased and the actual slub distance always decreased than the nominal values and the difference was significantly affected by the relative slub thickness while the actual slub relative thickness changed slightly. Outliers which are considered slub yarn defects were detected and counted in a final report by using the box plot statistical method. The effect of slub relative thickness, slub length percent and number of slubs per meter in periodic slub yarn samples of constant final count and twist factor on the actual geometrical parameters, twist distribution, physical properties and color coordinates difference in both of slub and base yarn parts were evaluated. Plain woven samples were produced from the produced periodic slub yarn samples in weft direction and the change in fabric properties was also evaluated. Results showed that slub part did not represent weak points with respect to the breaking force and abrasion resistance while slub relative thickness and slub length percent had a significant effect on base yarn properties. Results of the measured fabric geometrical and physical properties showed increase in fabric bulkiness, fabric smoothness, fabric assistance and a considerable increase in fabric tear strength measured in warp direction. The relationship between slub parameters in weft threads and fabric texture was investigated by using the statistical methods of image texture analysis and the correlation analysis showed that some of the second order statistical features obtained from the co-occurrence matrix had significant correlation with the parameters slub relative thickness and slub length percent.