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Presents a mathematical treatment of the large‐scale bending behaviour of multi‐ply yarn. Based on the assumptions that: each individual fibre in the yarn has the form of a doubly‐wound helix; each fibre is an inextensible slender rod; and interaction between fibres is ignored. The yarn‐bending rigidity is calculated as an average rigidity of an assembly of coaxial helices. There is good agreement between the predicted and measured values of yarn bending rigidity for a wool worsted knitting yarn. Also predicts the position, curvature and twist components as well as the strain energy of the deformed fibre.

Inter-fibre cohesion is regarded as an important property of assemblies, such as slivers, made of wool or any other fibres, with respect to the processing in carding, drawing (gilling) and spinning. In this paper, the results of the multiple regression analyses, and their validation, are presented to show that a strong relationship exists between the sliver cohesion (measured as sliver tenacity and sliver specific energy-to-break in a long-gauge tensile test) and a combination of the standard wool properties, such as bulk, mean fibre length (Barbe), mean fibre diameter and medullation content, used for the objective blend specification of New Zealand wools for marketing and processing.

A refined singles yam torsional model was built based on a previously developed singles yam model⁽¹⁾. The initial yam density distribution was found to be a very important yam parameter governing the torsional property of singles yams. Detailed study of the differential volumetric changes within the yam has shown that jamming of the structure is the key factor initiating longitudinal tensile and compressive strains in the fibres. The yam model was summarised in the form of a system of non-linear equations and the solution finding algorithm was presented.

The continuing development of the textile and clothing manufacturing industries depends in no small measure on the successful implementation of reliable objective methods for the specification, prediction and control of fabric quality and performance attributes. In the last decade, we have seen several notable examples of fabric design and development, and production and quality control in textile processing and clothing manufacture in terms of fabric objective measurement technology. The quality and performance characteristics of fabrics are related to their low stress mechanical, surface and dimensional properties. The experimental errors involved in the measurement of these properties are known to be much smaller than the errors involved in subjective assessment of fabric quality attributes, especially those made by individual judges. We may define the concept of fabric objective measurement as a necessary and sufficient set of instrumentally measurable parameters which are required to specify the fabric quality, tailorability and clothing performance. In this way, fabric objective measurement technology provides a “fingerprint” of the fabric quality, tailorability and performance implying that any two fabrics will generally differ at least to some extent in their objectively measurable characteristics. Fabric objective measurement technology therefore provides the key for scientific and engineering principles to be used for fabric specification and design as well as process control. The most important consequence of the introduction of fabric objective measurement technology will be the promotion of technological communication between various sectors of the textile and clothing industry, research and development workers and all other sectors of industry (e.g. fibre producers, retailing, merchandising, machinery manufacturers) concerned with fibres, textiles and clothing.

Textiles as clothing material must fit the human body and senses. This fitting is an important performance of the textiles besides the utility performance of textiles such as fabric strength. For many years, the performance concerning this fitness has been evaluated subjectively by hand judgement. The fabric property judged in such a way is called fabric handle. Instead of the subjective method, the objective evaluation system of fabric handle has been developed. The system is introduced firstly. In this objective method, the handle is evaluated based on the fabric mechanical and surface properties measured by the KESF instrument. The mechanical parameters of fabric measured by the instrument are useful not only for the fabric handle evaluation but also for textile and apparel engineering through the direct use of the parameters. The applications of the objective measurement of fabric handle and properties to textile and apparel engineering are introduced.

Outlines an approach to the problem of simulating the drape of fabrics. The approach is based on representing fabrics as two‐dimensional continua and using the differential geometry of surfaces to describe the shape of the draped fabric and to deduce deformation measures. The approach follows the philosophical approach previously used to establish computational models of elastica theory. Summarizes the mathematical model using a compact notation, with more detail being given in the context of a particular example. Uses a simple numerical solution procedure for the example, but this has limitations that indicate that more sophisticated techniques are needed. Points out possible difficulties with the graphical representation of drape, based on the experience of the simple example.

Non‐recovery of wool Futon padding was investigated by compression and creep tests. Simulation tests are also carried out to use the minuter model Futon. Fibre crimp was found to be an important parameter to be considered in the non‐recovery of Futon. Futon padding which consists of crimpy fibre has large apparent fibre density and shows less reduction of thickness compared with those made from uncrimpy fibres. The moisture inside and outside the Futon has a large influence on the recovery process.

Quality assessment and fault detection are important topics in textile research. Human assessment in this field, however, is subjective and slow. Presents an automatic assessment using two fundamentally different kinds of neural networks: the Kohonen Map (an unsupervised system) and the backpropagation network (supervised system). Evaluates two case studies using these techniques: assessment of carpet wear and the assessment of set marks. Both show good results when applied to the aforementioned problems. Makes a comparison between the two techniques and shows that the unsupervised system also gives an evaluation of the objectivity of the human experts.

We develop a model to relate the mechanical properties of individual fibers and how they are arranged in a fibrous assembly to the bulk properties of the fibrous assembly. The model allows the prediction of the bulk properties of the fibrous assembly during compression from the physical properties of its component individual fibers, considering both static and kinetic friction at contacts between fibers. Computer simulations are run for several cases with specific friction conditions applied in order to compare predictions of this model with experimental results and with van Wyk's theory of the uniaxial compression of an initially random fibrous assembly. These computer simulations demonstrate a reasonable ability to predict the undetermined constant K in van Wyk's theory. The computer simulations also show a significantly greater number of fiber‐fiber contacts being formed than theories based only on the diameter and arrangement of fibers have predicted. The predicted contacts have a wide range of contact forces, while only a small percentage of them do not slip. The model may be used to investigate phenomena associated with the compression of fibrous assemblies, such as fiber crimp, hysteresis, and orientation effects.

The method of the discrimination of the type and silhouette of ladies' garments was studied. Material samples of ladies' garments which had been judged good in appearance and comfort were collected. They were classified first into nine groups according to type and second each group was divided into two groups by silhouette (tight and loose fit). Basic mechanical properties of these fabric samples were determined by the KES‐measuring system. The result is as follows. Several equations for discriminating the type and silhouette of ladies' garments were derived on the basis of the basic mechanical parameters which determine the formability, elastic potential and drapability of the make‐up appearance of men's suits, these being bending, shearing property and fabric weight. These equations were able to be simplified by reducing the number of parameters to four in order to make the practical application of the equations easier.