35 research outputs found
Valuing air transportation and sustainability from a public perspective: Evidence from the United Kingdom and the United States
AbstractOne issue with air transportation and sustainability is that although aviation could be considered economically and socially sustainable, it does generate environmental concerns. The aim of this paper is to examine public attitudes towards air transportation and sustainability, in order to determine how individuals value sustainability in relation to air travel. This empirical paper is based on two large survey data sets, one from the East Midlands region of the United Kingdom and one from the East Coast of the United States. After an initial review of relevant literature and policy, a range of attitudinal statements from the surveys are examined. These statements cover the economic and social benefits of air transportation, the contribution of air travel to climate change, and environmental responses. The analysis demonstrates the high value individuals put on the economic and social sustainability aspects of air transportation. Although many acknowledge aviation's contribution to climate change, few are willing to respond in terms of paying more to offset the negative environmental effects of aviation or to fly less. When analysing the value of sustainability by population sub-group, flight frequency and gender are highlighted as key variables in terms of environmental attitudes
Energy absorption in lattice structures in dynamics: Experiments
Lattice structures offer the potential to relatively easily engineer specific (meso-scale properties (cell level)), to produce desirable macro-scale material properties for a wide variety of engineering applications including wave filters, blast and impact protection systems, thermal insulation, structural aircraft and vehicle components, and body implants. The work presented here focuses on characterising the quasi-static and, in particular, the dynamic load-deformation behaviour of lattice samples. First, cubic, diamond and re-entrant cube lattice structures were tested under quasi-static conditions to investigate failure process and stress–strain response of such materials. Following the quasi-static tests, Hopkinson pressure bar (HPB) tests were carried out to evaluate the impact response of these materials under high deformation rates. The HPB tests show that the lattice structures are able to spread impact loading in time and to reduce the peak impact stress. A significant rate dependency of load-deformation characteristics was identified. This is believed to be the first published results of experimental load-deformation studies of additively manufactured lattice structures. The cubic and diamond lattices are, by a small margin, the most effective of those lattices investigated to achieve this