Checked textile designs have many repeated patterns, so their distributions in the spatial frequency domains are partially concentrated. In addition, each distribution around local values in the spatial frequency domains can be approximately regarded as the normal distribution. By this property, it is possible to reconstruct distributions close to original distributions by using characteristic values of each distribution around local values. Moreover, in checked images, it is possible to obtain reconstructed images close to original images by using the data on the vertical and horizontal axes in the spatial frequency domains. So, we focused on reconstructing only distributions on the vertical and horizontal axes in the spatial frequency domains to compress checked images and used Gram-Charlier approximate equation to reconstruct the distributions. In this method, the mean, valiance, skewness and kurtosis [1-3] were used as characteristic values of the distributive shapes. Finally, we used only local values and these four data of distributive shapes around the local values as the compressed codes, and the other data aren't required. We propose the compressing method using these properties and show the effectiveness for checked images.

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Permanganic etching was performed on the high-speed spun and regular fibers of poly (ethylene terephthalate)(PET), and their surface morphologies were investigated using a transmission electron microscope. The high-speed spun PET fibers which have low molecular orientation in the amorphous regions showed peculiar surface morphology. That is, lots of small voids reflecting the disordered amorphous regions were observed. However, the number of such voids was extremely small for the regular PET fibers which have well oriented amorphous regions.

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In this work, pressure-thickness relation is investigated for a series of plain and rib knitted structures made from cashmere and polyester textured (PET) yarns. The pressure-thickness curve during lateral compression is divided into three regions, namely, the first linear region followed by the non-linear region and second linear region [1]. The portion of these regions and also the slopes of the linear regions are found to differ markedly by knit construction and yarn structure for knit fabrics. A comparison of cashmere and PET knits reveals that the compressibility primarily depends on fiber material. Besides, the compressibility of knitted fabric also depends on the structural parameters of loop length, cover factor and fabric weight.
On the other hand, in this study, the compression mechanism of knit fabrics, previously proposed by Postel [2], is modified to describe the experimental data more accurately. It becomes clear that the main structure of the knit fabric begins to deform at the second region of the pressure thickness curve and the main structure and the constituent yarns compressed mainly at the third region.

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In order to clarify the size effect of an interlacer, we measured air pressure distributions on the yam duct wall of interlacers with various sizes of both yarn duct and air jet nozzle for a wide range of the supplied air pressure in a rectification tank. The pressure in the yarn duct does not always increase with the supplied air pressure p and depends upon the diameter ratio R_d(=d/d_n), where d and d_n are the diameters of the yarn duct and the air jet nozzle, respectively. This is because expansion and compression waves occur alternately in the jet issuing from an air jet nozzle. In interlacers with R_d=2.0, at p=0.4 MPa the pressure p_s on the yarn duct wall of interlacers with L_d_??_3.0 takes a maximum at Z=0 and monotonously decreases to the atmospheric pressure with |Z|. Here, L_d is the non-dimensional yarn duct length defined by l_d/d(where l_d is the yarn duct length), and Z is the non-dimensional axial coordinate scaled by d and measured with respect to the center of an air jet nozzle exit. The value of p_s for L_d_??_3.7 takes a negative value near |Z|=1-3 and then increases to the atmospheric pressure. The value of p_s for L_d_??_7.0 is equal to the atmospheric pressure in |Z|_??_3. At p=0.2MPa, p_s having a maximum at Z=0 decreases monotonously with |Z| and equals the atmospheric pressure in |Z|_??_1. At p=0.4MPa, p_s monotonously decreases with |Z| in the interlacers with L_d_??_3.0 and R_d=2.4 or with L_d_??_2.3 and R_d=1.6. It may be supposed that interlacers with R_d=1.6 and L_d=3.7-7.0 have high processability because the pressure distribution in these interlacers expresses a large variation in space.

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