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The purpose of the study is to optimise the cross-sectional shape of passively cooled horizontally mounted pin-fin heat sink for higher cooling performance and lower material usage.

Multi-objective shape optimisation technique is used to design the heat sink fins. Non-dominated sorting genetic algorithm (NSGA-II) is combined with a geometric module to develop the shape optimiser. High-fidelity computational fluid dynamics (CFD) is used to evaluate the design objectives. Separate optimisations are carried out to design the shape of bottom row fins and middle row fins of a pin-fin heat sink. Finally, a computational validation was conducted by generating a three-dimensional pin-fin heat sink using optimised fin cross sections and comparing its performance against the circular pin-fin heat sink with the same inter-fin spacing value.

Heat sink with optimised fin cross sections has 1.6% higher cooling effectiveness than circular pin-fin heat sink of same material volume, and has 10.3% higher cooling effectiveness than the pin-fin heat sink of same characteristics fin dimension. The special geometric features of optimised fins that resulted in superior performance are highlighted. Further, Pareto-optimal fronts for this multi-objective optimisation problem are obtained for different fin design scenarios.

For the first time, passively cooled heat sink’s cross-sectional shapes are optimised for different spatial arrangements, using NSGA-II-based shape optimiser, which makes use of CFD solver to evaluate the design objectives. The optimised, high-performance shapes will find direct application to cool power electronic equipment.

Nano‐imprint forming (NIF) is a manufacturing technology capable of achieving high resolution, low‐cost and high‐throughput fabrication of fine nano‐scale structures and patterns. The purpose of this paper is to use modelling technologies to simulate key process steps associated with the formation of patterns with sub‐micrometer dimensions and use the results to define design rules for optimal imprint forming process.

The effect of a number of process and pattern‐related parameters on the quality of the fabricated nano‐structures is studied using non‐linear finite element analysis. The deformation process of the formable material during the mould pressing step is modelled using contact analysis with large deformations and temperature dependent hyperelastic material behaviour. Finite element analysis with contact interfaces between the mould and the formable material is utilised to study the formation of mechanical, thermal and friction stresses in the pattern.

The imprint pressure, temperature and the aspect ratio of grooves which define the pattern have significant effect on the quality of the formed structures. The optimal imprint pressure for the studied PMMA is identified. It is found that the degree of the mould pattern fulfilment as function of the imprint pressure is non‐linear. Critical values for thermal mismatch difference in the CTE between the mould and the substrate causing thermally induced stresses during cooling stage are evaluated. Regions of high stresses in the pattern are also identified.

Design rules for minimising the risk of defects such as cracks and shape imperfections commonly observed in NIF‐fabricated nano‐structures are presented. The modelling approach can be used to provide insights into the optimal imprint process control. This can help to establish further the technology as a viable route for fabrication of nano‐scale structures and patterns.

Effective teaching, while supplemented by best practice methods and assessments, is rooted in accurate, age-appropriate, and engaging content. As a foundation for history content, elementary educators rely strongly on textbooks and children’s literature, both fiction and non-fiction. While many researchers have examined the historical accuracy of textbook content, few have rigorously scrutinized the historical accuracy of children’s literature. Those projects that carried out such examination were more descriptive than comprehensive due to significantly smaller data pools. I investigate how children’s non-fiction and fiction books depict and historicize a meaningful and frequently taught history topic: Christopher Columbus’s accomplishments and misdeeds. Results from a comprehensive content analysis indicate that children’s books are engaging curricular supplements with age-appropriate readability yet frequently misrepresent history in eight consequential ways. Demonstrating a substantive disconnect between experts’ understandings of Columbus, these discouraging findings are due to the ways in which authors of children’s books recurrently omit relevant and contentious historical content in order to construct interesting, personalized narratives.

Defines “insider trading” and looks at the effects of insider trading on an economy. Considers the factors which have caused legislation and the rationale behind insider trading. Compares the economic and financial approaches to the problem. Outlines the European, UK and US positions covering legislation, arguments, prohibitions and penalties. Cites important cases in the USA, which have caused changes in the law. Concludes that there is a need for standardization, together with better access to timely information but highlights that the markets require freedom within which to work effectively and accepts that there will always be an element of insider trading in any market.