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Unusual mechanical properties of mechanical metamaterials are determined by their carefully designed and tightly controlled geometry at the macro- or nanoscale. We introduce a class of nanoscale mechanical metamaterials created by forming continuous corrugated plates out of ultrathin films. Using a periodic three-dimensional architecture characteristic of mechanical metamaterials, we fabricate free-standing plates up to 2 cm in size out of aluminium oxide films as thin as 25 nm. The plates are formed by atomic layer deposition of ultrathin alumina films on a lithographically patterned silicon wafer, followed by complete removal of the silicon substrate. Unlike unpatterned ultrathin films, which tend to warp or even roll up because of residual stress gradients, our plate metamaterials can be engineered to be extremely flat. They weigh as little as 0.1 g cm−2 and have the ability to ‘pop-back' to their original shape without damage even after undergoing multiple sharp bends of more than 90°.

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This chapter discusses the implementation of Wi-Fi technology in higher education of the United States. It includes Wi-Fi standards, security, the adoption of the technology, Wi-Fi to support teaching and learning, and challenges of Wi-Fi implementation. The last section is a case study of Wi-Fi at Ohio University. Although Wi-Fi technology has a great promise in higher education, institutions are still at the beginning stage of adoption. Institutions need to make a long-term sustainable plan to develop instructional strategies, successful practices, and technology supports to improve teaching and learning using Wi-Fi technology