In this paper we present a novel approach to calculate Block Time and Fuel (BTF) consumed for an aircraft model during a flight. The BTF model computes the ground distance between the origin and destination airports, derives the flight’s cruise altitude and by integrating two institutional data sets calculates the duration and the fuel consumed for the whole of taxi-out, take-off, climb, cruise, descent, approach, landing and taxi-in phases. We use the French Association for Operational Research and Decision Support (ROADEF) 2009 Challenge flight rotation to sample our model. The statistical analysis of the results consisted of comparing BTF results for the block time and those from the ROADEF Challenge 2009 with the real ones retrieved from Flightaware® for the same origin and destination airports and aircraft model. Statistical results are reported for percentile and root mean square error, and we show that, using simple calculations, the BTF computational results for block time are in a lower percentile and have lower root mean square error than the block times used by the ROADEF 2009 Challenge. To compare the fuel consumed, we used the values for the real flights published in the literature review. We were able to verify a good fit between the BTF results and those values. Since the BTF model computational results are obtained within a few seconds, we also conclude that the BTF model is suited for flight planning and disruption recovery in commercial aviation.

Islands offer unique model systems for studying fisheries development in relation to the growing global seafood trade. This study examines how export-driven fisheries in India's oceanic islands (Andaman and Nicobar Islands and Lakshadweep Islands) differ significantly as a result of their varied history, culture, available infrastructure and market access. Despite being geographically closer to export centres on the Indian mainland, processing and transport infrastructure in the Lakshadweep Islands are limited. This only allows for the trade of non-perishable commodities like dried tuna that are caught using traditional pole-and-line fishing techniques, restricting reef exploitation to local preference-based consumption and opportunistic export. The Andaman Islands, on the other hand, with multiple daily flight connections and large private and government processing facilities, are better connected to export markets. The relatively recent and multicultural fisheries of these islands supply marine commodity chains for reef fishery goods such as dried shark fins, frozen snapper fillets and chilled groupers. The Nicobar Islands are furthest away from mainland export centres and are mostly populated by indigenous communities – fishing here is mostly for subsistence and local sale. Revised estimates of travel times to export market centres are counterintuitive in terms of geographical distances and are significantly different from travel times to local markets.

Shooting angle of an inverse ray for imaging 2D multi-layered structures from reflected travel-times is derived in a closed form. By considering the normal incidence of two neighboring rays reflected at interfaces when sources are at the same locations as receivers, the traveling distance and direction of two inverse-rays are determined successively from the lowermost layer to the uppermost layer. This approach is similar to and also confirmed with the Huygens' principle that the equal travel-time along a wave front (perpendicular to the rays) is conserved. The closed-form solution of the inverse rays is further applied to image a complex structure of a ramp-flat fault with eleven layers. The results demonstrate that the inverse-ray imaging from travel-time picks of all layers is superior to that picked by a layer-stripping approach.

A more accurate estimate of the number of ambulances needed at disasters prevents vehicles from being withdrawn unnecessarily from their “normal” duties, thereby curtailing needless expense and helping to ensure that disaster sites are not overcrowded with emergency workers impeding each other's effectiveness. This article discusses a formula for determining the number of ambulances needed at a disaster.