The Flying Fish platform is an ocean, environmental monitoring buoy that repositions as an Unmanned Aerial System (UAS), maintaining a pre-set watch circle. To operate in the open ocean, the platform must be robust to moderate sea state conditions and must function unattended thus fully-autonomously. Our concept was conceived as an alternate solution to surface boat designs, avoiding the hydrodynamic drag of ocean waves and currents while in flight. Over the first project year, we developed and repeatedly demonstrated our prototype vehicle's ability to autonomously "hop" across a GPS-defined "watch circle", providing initial validation of the unified UAS-buoy (air/sea vehicle) persistent ocean monitoring concept. This paper will describe the vehicle design and performance characterization through simulation and flight-testing and provide insight to the Phase II vehicle which will operate for long periods with a balanced energy budget.
We propose an abstraction, named BEC, to enable Global Address Space (GAS) capabilities for parallel programming in SPMD style . It is a portable lightweight approach for incremental acceptance of the GAS model, along an evolution path that leverages existing infrastructures and maintains backward compatibility with existing programming methods and environments . It assists migration of legacy applications thereby encouraging their expert programmers to adopt the new model.In addition, it provides for some of the unaddressed needs, such as efficient support for high-volume fine-grained and random communications, which are common in parallel graph algorithms, sparse matrix operations, and large scale simulations . The idea behind BEC is that messages are aggregated by a runtime library for bulk transport to handle such unpredictable communication patterns . Data from initial experiments with a prototype communication bundling library using the Bundle-Exchange-Compute (thus motivating the name BEC) programming style shows that this approach scales well. As examples of suitable BEC applications, we present sparse matrix kernels for multiplication and overlapping Schwarz preconditioning [5,11] . We also discuss solid mechanics material contact [1,18] with abundant irregular, fine-grained communication. BEC can be used as an enhancement to existing environments such as MPI . It can also function as an intermediate language [14] to other high level GAS languages such as PRAM C [8] and UPC [30] . Furthermore, it can serve as a bridge between programming models such as virtual shared memory and message passing. pointed out the link between the BSP model and BEC . Thanks to Ron Brightwell and Rolf Riesen for helpful discussions on OS, MPI, and network issues . Mike Glass, Kevin Brown, and Courtenay Vaughan helped us a great deal by providing us with valuable insight into internal workings of Sandia software for simulation of material contacts. Bruce Hendrickson and Steve Plimpton taught us about algorithms used in Sandia's contact libraries . Doug Doerfler and Brice Fisher asked pertinent questions which motivated us to formalize the BEC model . This research used resources
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