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Now showing items 11-20 of 41
Heterogeneous underwater networks for ASW: technology and techniques
(NURC, 2008/06)
NATO's research and technology objectives for anti-submarine warfare (ASW) include persistent scalable heterogeneous wide-area surveillance networks for the littoral environment. Network and system design considerations ...
Security versus defence: dual use from a system requirement perspective
(NURC, 2008/09)
The developers of defence technologies in both industry and national laboratories carried their culture for military system development into the evolving security mission, even for systems that are to be used by civilian ...
Geoacoustic inversion using multipath pulse shape
(NURC, 2008/09)
Experimental data, measured in a shallow water region of the Mediterranean Sea, are used to show that the variation of received intensity with time is well described by existing expressions [Harrison and Nielsen, J. Acoust. ...
Cardioid receive array calibration for active systems
(NURC, 2006/08)
Nowadays active detection improvement relies significantly on advanced sensor technology, such as the cardioid receive array that allows the directional (right/left) discrimination of the received signal. However, in ...
Multipath pulse shape in a refracting environment
(NURC, 2007/11)
Multiple boundary interactions in shallow water propagation introduce a more or less Gaussian angle distribution at a distant receiver. When all paths are added the result is 'mode-stripping', i.e. the steep rays are ...
Shallow water synthetic aperture sonar: an enabling technology for NATO MCM forces
(NURC, 2007/10)
The change in military focus from Cold War doctrine to expeditionary operations in shallower littoral water and the heightened terrorist threat to ports and their approaches, have put increased emphasis on countering ...
At-sea measurements of acoustic elastic scattering by a 1.5m-long cylinder made of composite materials
(NURC, 2007/12)
Monostatic and bistatic acoustic scattering measurements were performed on solid-filled fibreglass objects (a sphere and a cylinder with hemispherical endcaps) deployed proud on a sandy seabed and insonified by a rail-mounted ...
The dynamics of information fusion: synthetic versus misassociation
(NURC, 2006/08)
Fusion entails both the association and synthesis of information. If missassociations occur, they obviously undermine the gains won by synthesis, compromising the fusion product. An analytic framework is presented here to ...
Geo-spatial tactical decision aid systems: fuzzy logic for supporting decision making
(NURC, 2006/08)
Tactical decision aid systems support
Multipath pulse shapes in shallow water: theory and simulation
(NURC, 2007/04)
In shallow water propagation the steeper ray angles are weakened most by boundary losses. Regarding the sound intensity as a continuous function of angle it can be converted into a function of travel time to reveal the ...