This paper investigates the impacts of weave structures and weft density on the Poisson's ratio of worsted fabric under uniaxial extension. In this study nine groups of worsted fabrics comprising of three weave structures (twill 2/2, twill 3/1 and hopsack 2/2), each produced in three different weft densities were examined. Samples were extended in weft direction uniaxially and the Poisson's ratio of fabric in various extensions was measured. Analysis showed that the effect of both weft density and weave structure are significant with no combination effect on the Poisson's ratio. It was found that there is an exponential correlation between warp and weft crimp during fabric extension. For the worsted fabrics used in this research in all three fabric structures, fabrics with higher weft yarn density have higher value of Poisson's ratio. It was also concluded that for the fabrics with the same condition but only different in structures, this ratio is related to the structural firmness of fabric. In all three fabric structures the value of the Poisson's ratio were following the same pattern of twill 2/2, twill 3/1 and hopsack 2/2 from highest to lowest value. It was revealed that there is a high linear correlation between the crimp interchange ratio and Poisson's ratio.

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In the present paper, a response surface model has been introduced to predict the geometrical parameters of heat set polypropylene pile yarns. The input factors of the presented model include yarn twist, initial yarn count, time, and temperature of heat setting and the response factors are yarn count, yarn shrinkage, crimp contraction and packing factor after the heat setting process. To analyse the effect of this process on the yarn parameters, the dry heat setting process has been applied to all samples at different times and temperatures using an oven equipped with air circulation because of better accuracy and control of temperature. The obtained results showed that there is a positive relation between time and temperature and output parameters. Finally, the predicting equations discussions about the optimum points for maximum shrinkage and interactions of parameters have been presented. Hence, due to some disability of the RSM method, an ANN model has been designed to predict the parameters at higher accuracy. The results of the accomplished ANN model represent a higher prediction correlation coefficient compared to RSM.

This paper presents a study on the bending behavior of rectangular textile patch antennas including analytical modeling, full wave simulations, and experimental measurements.In the proposed analytical model, the textile patch antenna was treated as a laminated composite beam. Therefore, after locating the position of neutral axis considering the tensile modulus and the dimensions of each layer, the classic cylindrical cavity model was modified to predict the relation between resonance frequency and bending curvature, taking into account the patch's elongation. Since the presented interdisciplinary analytical approach is associated with a set of simplifying assumptions, a full wave model was also utilized to study this effect. All the simulations were performed in two modes; patches with fixed and elongated dimensions. Finally the results of both models were compared with the experimental measurements and the effects of bending on the resonance frequency of textile patch antennas were discussed in more detail. The obtained results showed that some parameters including the direction of bending, substrate thickness, and mechanical properties of antenna's components can alter the textile patch antenna's behavior under bent conditions.

One of the major applications for nonwoven fibrous system is as thermal insulation materials. Many factors may affect thermal properties. This research attempts to study the effects of punch density and fiber blends on heat transfer in nonwoven. For this purpose the samples, whose properties are analyzed by using static methods for measuring their thermal conductivity, were constructed in blends of polyester with polypropylene. The blend ratios are 100% PET, 80/20, 60/40, 40/60, 20/80, and 100% PP. Six samples were produced from each blend by changing the primary needle punch density to115, 135, 155, 175, and 195 punches per cm 2 . The secondary needle punch density was held constant at 120 punches per cm 2 . The temperature of the hot plate, i.e. the applied temperature, was 40°C.Experimental results show that with increasing punch density and pressure, heat transfer decreases. Moreover, the results indicate that the blending of fiber types causes a reduction in fabric heat transfer.