Textile Research Journal current issue

Geometrical Models for Cardigan Structures Part II: Half Cardigan

Kurbak, A., Alpyildiz, T. — Fri, 13 Nov 2009 06:36:58 PST

A geometrical model for the half cardigan structure is presented based on the model of full cardigan structure given in Part I of this series of papers. In the model, loop and tuck stitch heads are taken as ellipses in two dimensions. The rest of the loops and tucks are taken as parabolic helices wrapped on elliptical cylinders in general. The parameters of the model were obtained by using a wash-relaxed wool fabric at medium tightness. Computer drawings of the model were created by the 3DS MAX graphical program, which gave similar loop shapes to those observed in real fabrics.

Predicting Seam Performance of Commercial Woven Fabrics Using Multiple Logarithm Regression and Artificial Neural Networks

Hui, C. L., Ng, S. F. — Fri, 13 Nov 2009 06:36:58 PST

In this study, the capability of artificial neural networks and multiple logarithm regression methods for modeling seam performance of commercial woven fabrics based on seam puckering, seam flotation and seam efficiency were investigated. The developed models were assessed by verifying Mean Square Error (MSE) and Correlation Coefficient (R-value) of test data prediction. The results indicated that the artificial neural network (ANN) model has better performance in comparison with the multiple logarithm regression model. The difference between the mean square error of predicting in these two models for predicting seam puckering, seam flotation, and seam efficiency was 0.0394, 0.0096, and 0.0049, respectively. Thus, the ANN model was found to be more accurate than MLR, and the prediction errors of ANNs was low despite the availability of only a small training data set. However, the difference in prediction errors made by both models was not significantly high. It was found that MLR models were quicker to construct, more transparent, and less likely to overfit the minimal amount of data available. Therefore, both models were effectively predicting the seam performance of woven fabrics.

Separation of Clustered Fibers in Cross-sectional Images using Image Set Theory

Wan, Y., Yao, L., Xu, B., Wu, X. — Fri, 13 Nov 2009 06:36:59 PST

Fiber cross-sectioning often creates fiber clusters in microscopic images, in which fibers touch or overlap each other. Prior to any geometrical analysis, it is critical to separate touching/ overlapping fibers so that the features of individual fibers, not fiber clusters, can be identified. Automatic separation of irregular, complex fiber cross-sections remains challenging in image analysis for fiber characterization and measurements. This paper introduces an algorithm based on the image set theory to separate clustered fibers in cross-section images. An image is partitioned into three subsets, fiber edges, fiber interiors, and background. The Euclidean distances between edge pixels and interior pixels are used to assign the edge pixels to specific interiors. The assignment leads to the divisions among the merged edge pixels. The experimental results demonstrated that the new algorithm can optimally separate clustered fibers of various cross-sectional shapes, including W-shaped and cross-shaped fibers.

Numerical Model of an Air-jet Loom Main Nozzle for Drag Forces Evaluation

Belforte, G., Mattiazzo, G., Viktorov, V., Visconte, C. — Fri, 13 Nov 2009 06:36:59 PST

The flow field inside an air-jet loom main nozzle is studied numerically, by means of a two-dimensional model implemented in the commercial computational fluid dynamics (CFD) code Fluent. In order to determine which physical model could allow a better prediction of the nozzle behavior, preliminary simulations were carried out on a basic geometry configuration, changing flow models and comparing results with available experimental data. Having done the model setup, simulations aimed at evaluating drag force on the weft yarn were performed on various geometry configurations; in particular, the influence of acceleration tube length, shape and size on drag force was evaluated. Results gave some guidelines for future prototyping and experimentation.

A Novel Design Method for an Intelligent Clothing Based on Garment Design and Knitting Technology

Li, L., Au, W.M., Li, Y., Wan, K.M., Chung, W.Y., Wong, K.S. — Fri, 13 Nov 2009 06:36:59 PST

The design elements of intelligent clothing were studied in this research. Both garment design as well as knitting technology concepts were applied to wearable electronic garments with aesthetic, functional, and technical features. In addition, a new garment design method is proposed for a specific task based on combinations of garment design and knitting technology to provide the required confining pressure, and electrical and mechanical properties for the intelligent clothing and also to take into account the requirements for aesthetics. Garment design skills of sewing, attaching accessories, embroidery, cutting, etc. can enhance the functionalities of the knitting technology. Garment design and knitting technology complement each other and provide a greater degree of freedom in intelligent clothing design. Experiments revealed that problems faced in intelligent clothing design, such as confining pressure, flexible electronic circuitry, aesthetic, appearance, and so on, could be successfully solved by the use of different garment design skills and knitting technologies. A garment design application model was set up based on this new design method and can be applied in the future design of intelligent clothing.

A Hybrid Planning Process for Improving Fabric Utilization

Wong, W.K., Leung, S. Y. S — Fri, 13 Nov 2009 06:36:59 PST

In the textile and clothing industry, marker planning is a critical operation in the fabric-cutting room, in which pattern pieces of different sizes and styles of a garment are laid out on a sheet of paper with fixed width and arbitrary length in order to achieve the highest fabric utilization (marker efficiency). The layout always contains areas of unusable fabric due to the irregular shapes of garment pattern pieces. The minimization of fabric wastage is crucial to the reduction of production costs. In this study, a methodology that hybridizes a heuristic packing (HP) approach based on grid approximation with an integer representation-based (µ + ) evolutionary strategy (ES) is proposed in order to obtain an efficient layout of garment patterns so as to optimize the fabric utilization. The performance of the proposed methodology is validated by the experiments and the results demonstrate that the proposed method provides an effective means by which to increase the marker efficiency.

Comparison of the 2-D Deformation of Ironed and Non-Ironed Plain Weave Fabric during Relative Humidity Cycles

Bhouri, N., Badel, E., Perre, P., Bennasrallah, S. — Fri, 13 Nov 2009 06:36:59 PST

The 2-D deformation of bleached plain weave cotton ready-to-wear clothing was measured during adsorption and desorption cycles. A digital X-ray imaging system was coupled with a climatic chamber to control temperature and relative humidity. An image of each sample was recorded for several equilibrium states. The strain along warp (_cc) and weft (_ww) directions and the shear deformation (_wc) were evaluated by image correlation process. The dimensional variations are explained by geometrical consideration of the structure at microscopic (fibers scale) and macroscopic levels (yarns scale). Indeed, the reaction between water vapor molecules and material enlightens two steps. At first, the swelling fibers fill the micropores inside the yarns. Then, the yarns swell and push on their neighbors to fill up the macropores and cause the macroscopic swelling of the overall structure. During the desorption phase, the fibers shrink to create a free space inside the plain weave structure that will be relaxed to find its initial state. The isotropy between the two main directions is explained by the weave symmetry and the similar yarn properties. The shear deformation is related to the cohesion by twist between cotton fibers. This work is more specifically focused on the ironing process (T = 200°C + steam). The ironing generates flattened yarns and increases their friction, which amplifies the deformation during the first adsorption cycle. However, this effect is cancelled at the end of the first adsorption/desorption cycle with no memory effect of the ironing process.

Three-dimensional Simulation of the Dynamic Yarn Behavior on Air-jet Looms

De Meulemeester, S., Puissant, P., Van Langenhove, L. — Fri, 13 Nov 2009 06:36:59 PST

This paper deals with the three-dimensional computer simulation of the weft insertion process as a possible solution to avoid costly weaving trials when researching this process. A three-dimensional mathematical model of the yarn was developed, in which the behavior of the yarn was described by the Second Law of Newton. For this mathematical model, a second order differential equation needed to be solved. To this end, an explicit integration using Euler’s method was chosen. In order to validate the model, high-speed camera recordings were performed on a test stand and compared with simulations of the same test stand. A very good resemblance was found between simulation and camera recordings. This is the first time that a three-dimensional model for the weft insertion on air-jet looms has been successfully tested.

Shapeable Stretch Textiles via Simple Weaves for Seamless Woven Fashion

Wang, X., Ng, F.M.C., Hu, J., Seto, Y.-c. — Fri, 13 Nov 2009 06:36:59 PST

This paper proposes approaches to create shaped woven textiles (SWTs) for seamless woven fashion by designing diverse simple weaves and applying their dimensional changes. A widespread stretch material (spandex) was selected as the main fillings for shape changes. The research introduces the four design parameters of simple weaves for stretch fabrics. Twenty types of specimens in two different configurations of the stretch fillings were then produced. Correlations between the four parameters and dimensional changes of simple weaves were investigated. With respect to dimensional and textural changes, experimental results indicated corresponding divergences of specimens made by the different simple weaves and two types of configurations of fillings. By integrating these shape changeable weaves via jacquard designs, several practical creations illustrated the sculptural capabilities of shaped textiles and aesthetical attributes. This research contributes to the integrated design and manufacture of future woven textiles and fashion.

Nanosols Textiles

Schollmeyer, E. — Fri, 13 Nov 2009 06:36:59 PST

Abstracts: Sen'i Gakkaishi, Vol. 65, No.12

Fri, 13 Nov 2009 06:36:59 PST