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The experimental setup for studying fibre orientation effects on air permeability of fibrous layers is described. The orientation parameter is obtained through small-angle scattering by laser radiation. Experimental dependence of pressure drop on air velocity follows Darcy's law. Permeability factors depend on orientation parameters and effective density of porous layers. It is demonstrated that for a fibrous layer porosity of ε > 0.9, the streams around individual fibres may be considered independent.

In such a case, the resulting force acting on the entire layer can be defined by force summation over individual fibre length. Resistance force acting on the unit segment of a fibre inclined at an angle to the flow direction is specified by the formula involving two empirical constants, which defines longitudinal and transversal resistance factors.

Integrating the procedure over all possible fiber directions that are defined by axially symmetric angular distribution density gives the resistance force acting on the entire layer of fiber and also pressure drop value. A comparison with obtained experimental data gives the values of transversal and longitudinal resistance factors. Their ratio, which approximately equals to 2, fits the findings of other publications

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.

Refers to how the mechanical properties of polymer‐based composite objects produced via rapid layered fabrication methods can be improved significantly using short discontinuous fibres as reinforcements. Notes in this context, that the viscosity of the uncured fibre‐photopolymer composite liquids affects the raw‐material handling, the layer formation and the draining operations. Assesses the effects of aspect ratio, surface coating and volume fraction of short glass fibres on the viscosity of the fibre‐photopolymer composite liquids. Based on extensive experimentation and analysis, concludes that the shear viscosity of the composite liquids increases with increasing fibre‐volume fraction, showing that this effect is more pronounced at low shear rates than at high shear rates. Reveals, similarly, that the aspect ratio of the dispersed fibres has a stronger effect on the increase of viscosity at low shear rates and that the surface coating of the dispersed fibres also affects the viscosity of the composite liquids.

Angular distribution of relative fibers length is worked out theoretically for flat and axial symmetric fibrous structures. Indices of fibers configuration, fibers orientation and integrated one are introduced and defined using this distribution. Fibers configuration indices are compared with these obtained by direct method.

This paper aims to reports the further developments of an optical sensing technique, relying on Mie scattered and reflected light, from the ice surface and volume, to determine the ice accretion rate as well as the ice type.

By measuring the optical intensity of the backscattered and reflected light, the paper demonstrates that it is possible to obtain information on the onset of icing as well as determine the thickness and type of ice accreted on the leading edge of a wing in real time.

This work is important in the design and development of optical direct ice detection sensors for aerospace applications.

This work is aimed at showing a new approach to ice detection.

Original concept follow on paper from pervious publication.

The purpose of this paper is to provide a comparative review of intensity‐modulated fiber optic sensors with non‐optical sensors for health monitoring applications, from the current research activities in the area.

A range of published research work in sensor design for four different health monitoring applications, including, lumbar spine bending, upper and lower limb motion tracking, respiration and heart rate monitoring, are presented and discussed in terms of their respective advantages and limitations.

This paper provides information on the various types of sensors applied into the health monitoring area. The sensing techniques of the fiber optic sensor for the stated applications are focused and compared in details to highlight their contributions.

A comparative review of published work is illustrated in an informative table content, to allow a clear idea of the current sensing approaches for health monitoring applications.

Sensor Review publishes the results of a major sensor survey.

The small-angle scattering method is applied to study the: straightening and parallelization of fibres in the air stream; feeding sliver indices as influenced by those of the rotor fibre ring under open-ended spinning; orientation of fibres in some non-woven fabrics; continuous measurement in slivers. The straightening of discrete fibres in the air stream in a convergentdivergent duct is studied under a change in flow rate, with the rotational speeds of feeding sliver and discharging rollers varying with two modifications of the discharging roller, and with different feeding sliver types.

Deals with the optical responses of fibre Bragg grating (FBG) sensors under different modes of deformation. It derives both the polarisation states and reflection spectra of FBGs based on coupled mode equations by considering the deformation perturbations. It conducts numeric simulations, finds that the experimental results agree well with the simulated ones for normal germano‐silicate FBGs under different individual modes of deformations.

A FEATURE of many of the light alloys now in common use is that the stress and strain curve often does not evidence any well defined region in which the elastic strain becomes plastic strain, and a linear portion of the diagram from the origin, which in the case of so many metals represents a region of proportionality, is sometimes almost non‐existent, the diagram being curved right from the origin so that it is not possible to define any region or limit of proportionality, and the proof stress; by standard definition, has accordingly a relatively low value compared with the ultimate tensile stress of the alloy concerned. (Fig. 1).