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A literary criticism of the book "Mogreb-El-Acksa: A Journey in Morocco," by Robert Cunninghame Graham is presented. It explains how the author traversed Orientalist literary discourse. The article also discusses Cunninghame Graham's relations to his literary peers, especially his friend Joseph Conrad.

The traditional approach to drape modeling for fabric reinforcements uses a geometric mapping based on fabric shear. This approach provides a fast solution even for complex geometries and is now employed within a number of commercial simulation packages. Given a user-defined material orientation and starting point, such codes will provide a unique draped fiber pattern for a particular component. However, industrial experience shows that a range of solutions is possible, depending on the choice of reinforcement and in particular the initial fiber architecture. This paper describes an alternative approach, in which conventional geometric mapping is used within an iterative scheme based on fabric mechanics. A mechanical model of fabric shear is developed based on a geometric description for woven and non-crimp fabrics. This model is used to predict shear force and hence shear strain energy as a function of fabric shear angle. Shear strain energy is summed over the surface of the draped geometry to provide a measure of deformation energy. This is minimized within an iterative scheme to provide the most likely draped fiber pattern for a particular fabric. Predicted results are compared with a number of experiments to demonstrate the validity of the model for both generic geometries and an automotive demonstrator component. [ABSTRACT FROM AUTHOR]

This study analyses the influence of the random filament arrangement in fibre bundles on the resin flow behaviour. Transverse steady-state resin flow that occurs behind a liquid resin flow front was simulated numerically through statistically equivalent micro-structures at high-fibre volume fractions, Vf > 0.6, as observed in fibre bundles. The need of applying a minimum gap distance between neighbouring filaments was overcome by automated local mesh refinement. The derived permeability values showed significant scatter. Convergence of these values was determined at a ratio of flow length to filament radius greater than 20 for all three analysed fibre volume fractions. Mean permeabilities were between 6 and 10 times lower than those predicted for a hexagonal fibre array. A statistical model is proposed, which is able to predict the scatter of observed permeabilities based on simple micro-structural descriptors. [ABSTRACT FROM AUTHOR]

Meso-scale unit cell models are often used to simulate mechanical behaviour of textile composites. Apart from reliable ways to create meso -scale geometries, such simulations require reliable meshing algorithms. While the former is made possible via dedicated textile pre-processors or high-fidelity weaving simulations, the meshing remains quite problematic for complex textiles and geometries. Even though, with a lot of user input, it is possible to create very complex meshes using meshing pre-processors, this approach remains infeasible for cases when a large number of models need to be analysed. This paper presents a meshing approach based on the combination of local octree-refinement with surface smoothing. This allows nearly conformal meshes to be generated for geometries of any complexity which achieve accuracy comparable to that of conformal meshes. A range of unit cells was analysed using the new approach and it was shown that the error in local stresses is within 10% of the reference solution and the average error is below 7%. It was found that the computational cost of the analysis using the new meshing technique is not considerably higher than for an analysis which uses a conventional conformal mesh yet the new approach allows analysis of any geometry. [ABSTRACT FROM AUTHOR]

Microscopic observation and analysis are used to examine the role that contact conditions play in determining the frictional behaviour of non-crimp fabrics (NCFs). The true fibre contact length is measured over a range of normal pressures. For the NCF considered, the contact length is 67% lower than for a corresponding unidirectional tow-on-tool contact at a pressure of 240 kPa. The difference in contact behaviour is associated with the fabric architecture, specifically stitching and gaps between tows. These microscopic observations are used to predict friction using a constant interface shear strength model. These predictions are found to compare well with macroscopic friction measurements taken using a sliding sled arrangement, once the roughness of the sled tool is taken into account. [ABSTRACT FROM AUTHOR]

Two complementary dipyrromethane + dipyrromethanemonocarbinol routes to a meao-substituted 5-isocorrole were investigated. While both routes could afford the identical 5-isocorrole, selfcondensation of the different dipyrromethanemonocarbinol precursors could potentially lead to a second porphyrinoid of different structure (a porphyrin or a porphodimethene). The two reaction routes were examined to compare the distribution of porphyrinoid products, probe the effect of key reaction parameters on the product distribution, and identify conditions for the efficienl preparation of the 5-isocorrole so that its spectral properties and stability toward light and air could be assessed. For each route, a systematic survey of reaction parameters was performed via analytical-scale reactions monitored for the yields of the 5-isocorrole and self-condensation product by HPLC. The two reaction routes were found to afford very different product distributions in accordance with the anticipated nucleophilicity of the dipyrromethane and dipyrromethanemonocarbinol precursors. The most promising reaction condition (InCI3, 0.32 mM) was performed on a preparative-scale providing the 5-isocorrole in an isolated yield of 31% (102mg). Spectroscopic analysis was consistent with the 5-isocorrole structure. The stability of the 5-isocorrole in dilute solution upon exposure to light and air was assessed by UV—vis spectroscopy and HPLC and was found to be excellent. [ABSTRACT FROM AUTHOR]

Abstract: An area of interest in the automated manufacture of composite components is the prediction in real-time of the deformed shape of a textile reinforcement in 3D space during robotic handling operations. The deformed shape can be used to guide robotic end-effectors to ensure accurate fabric placement and avoid collisions. In this paper, a nonlinear mathematical model using large deflection plate and shell theories is presented. The model is able to predict the 3D deformed shape of limp sheet materials being picked-up by multi robotic grippers for three boundary conditions. The main factors affecting the deformation behaviour of the sheet during the operation are identified and analysed, and the contributions of different energies during deformation are presented in detail. Good agreement is obtained when comparing the solutions of the model with FE simulation results. This study demonstrates the possibility of developing a modelling capability for material on-line response in automatic flexible material handling. [Copyright &y& Elsevier]

In numerical simulations of reinforcement preforming, fabrics are often modelled using continuum approaches with homogenised material properties in order to reduce the computational costs. To predict the occurrence of meso-scale defects, in particular when membrane finite elements are used for modelling, a novel wrinkling criterion is proposed here. This criterion relates the onset of reinforcement buckling to material and process parameters. It is demonstrated that the criterion correctly predicts the occurrence of meso-scale defects and is more accurate than criteria based on a constant shear locking angle or critical strain for the defect onset, which do not to take into account local processing conditions such as friction or normal pressure. [ABSTRACT FROM AUTHOR]