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Unsaturated polyester/nanoclay (UP/NC) composites were developed using an optimized process, which combines high shear mixing (HSM) and ultrasonication. Different types of organically modified nanoclays (Cloisites 10A and 20A and Nanomer I.30E) were considered with I.30E resulting in the best morphology with an exfoliated structure. This and the higher aspect ratio of I.30E lead to its better performance under tensile and flexural testing. Different loadings of I.30E (0, 1, 2, 3, and 4 wt%) were thus used to manufacture UP/NC nanocomposites and test their resistance to water uptake as well as the moisture ingress effects on their mechanical properties. The results showed that the addition of I.30E nanoclay enhanced the hydrophobicity of the nanocomposite with a maximum improvement of about 40% at 4 wt% of NC loading. Flexural test results revealed relative degradation in the flexural properties of neat UP and UP/NC, due to moisture uptake. However, the reduction in flexural properties was found to be minimal at the optimum nanoclay loading of 3 wt%.

A software visualization tool is developed to help in teaching core power systems analysis problems in introductory undergraduate courses. The power system analysis concepts visualization tool consists of simulation applications that focus on three problems: load flow, economic dispatch, and unit commitment. It incorporates user-friendly effective graphical interfaces that aid students in acquiring deeper understanding of the power system problems and developing the analytical skills needed in industry. The learning tools are implemented in C# language for platform-independence to increase accessibility. Evaluation of the visualization tool shows very encouraging results.

This paper deals with the development of friction stir diffusion bonding between 2 mm thick 5052 Aluminum alloy and Cold rolled Steel for cladding application. The investigation focuses on the effect of process conditions on tensile-shear strength of produced lap joint by considering four independent welding parameters: tool rotational speed, welding speed, tool axial force and tool offset in the consecutive pass. A short tool-pin was utilized to avoid tool penetration into the steel substrate and mechanical mixing between clad material and the substrate. In order to optimize the process parameters for maximum joint strength and minimize the number of tests, Taguchi orthogonal array L9 with four factors and three levels was used. Results revealed that tool rotational speed had the greatest influence on produced weld strength. On the other hand, the tool pin length or penetration depth was found to have more effect on weld strength than the axial force. Moreover, clamps’ rigidity had a great impact on joint strength. For the selected material and tool, the optimum welding conditions were found to be 1000 rpm rotational speed, 12 kN plunging force, 100 mm/min welding speed and 12 mm tool offset.

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