Browsing Reprints by Issue Date
Now showing items 381-400 of 548
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Counter piracy surveillance requirements for early detection, military rescue, or evasion
(NURC, 2012/06)Best practice for protection against pirates includes coordination with the military forces operating in the area, constant watch against the approach of pirates, and measures to prevent or delay their boarding. The time ... -
Benefit assessment of glider adaptive sampling in the Ligurian Sea
(CMRE, 2014/01)The benefits of piloting a glider during a 6-day period via an adaptive sampling procedure in a 80 × 60 km2 marine area are assessed under a fully operational framework. The glider trajectory was adapted to reduce the ocean ... -
Underwater source localization using a hydrophone-equipped glider
(CMRE, 2014/01)Buoyancy-driven underwater gliders are autonomous underwater vehicles that were originally developed to collect oceanographic data. CMRE is studying the use of this technology for the characterization of denied areas, ... -
Range estimation of cetaceans with compact volumetric arrays
(CMRE, 2014/01)Passive acoustic monitoring is the method of choice to detect whales and dolphins that are acoustically active and to monitor their underwater behaviour. The NATO Science and Technology Organization Centre for Maritime ... -
Vessel pattern knowledge discovery from AIS data: a framework for anomaly detection and route prediction
(CMRE, 2014/01)Understanding maritime traffic patterns is key to Maritime Situational Awareness applications, in particular, to classify and predict activities. Facilitated by the recent build-up of terrestrial networks and satellite ... -
A novel approach for a bistatic scattering calculation suitable for sonar performance model
(CMRE, 2014/01)One of the classical approaches to the calculation of the sound pressure scattered from a rough surface is to sum the contributions to the field from a set of small tiles that approximate the surface. If the tiles are ... -
Performance assessment of the MUSCLE synthetic aperture sonar
(CMRE, 2014/01)Synthetic Aperture Sonar (SAS) systems are quickly becoming fundamental tools for seabed mapping applications, as they provide high resolution imagery independent of range from the sensor, with high area coverage rates. ... -
Ray convergence in a flux-like propagation formulation
(CMRE, 2014/01)The energy flux formulation of waveguide propagation is closely related to the incoherent mode sum, and its simplicity has led to development of efficient computational algorithms for reverberation and target echo strength, ... -
A relation between multipath group velocity, mode number, and ray cycle distance
(CMRE, 2014/01)Weston's ray invariant or "characteristic time" in a range-dependent environment is exactly equivalent to the Wentzel-Kramers-Brillouin phase integral for ducted normal modes. By considering a ray element it is shown that ... -
Localization of small surface vessels through acoustic data fusion of two tetrahedral arrays of hydrophones
(CMRE, 2014/01)Detection and tracking of vessels is important in confined areas such as marine parks or harbors. Nowadays, the presence of ships can be accurately monitored either by radar or via AIS system, while small vessels, which ... -
Efficient dense sonar surveys with an autonomous underwater vehicle
(CMRE, 2014/01)An algorithm for the in situ adaptation of the survey route of an autonomous underwater vehicle (AUV) equipped with side-looking sonars was recently proposed. This algorithm immediately exploits the through-the-sensor data ... -
Optimum sampling designs for a glider-mooring observing network
(CMRE, 2014/01)Ocean observing systems (OOSs) constituted by moorings and gliders are becoming relevant in oceanographic and climate studies. In these observing networks, the temporal variability is captured by mooring observations, while ... -
Oceanographic field estimates from remote sensing and glider fleets
(CMRE, 2014/01)This work investigates the merging of temperature observations from a glider fleet and remote sensing, based on a field experiment conducted in an extended coastal region offshore La Spezia, Italy, in August 2010. Functional ... -
Maritime surveillance using multiple high-frequency surface-wave radars
(CMRE, 2014/05)In the last decades, great interest has been directed toward low-power high-frequency (HF) surface-wave radars as long-range early warning tools in maritime-situational-awareness applications. These sensors, developed for ... -
Detection, tracking and fusion of multiple HFSW radars for ship traffic surveillance: experimental performance assessment
(CMRE, 2014/05)Low-power HF surface-wave radars fit well the role of long-range early-warning tools in maritime situational awareness applications, by virtue of their over-the-horizon coverage capability and continuoustime mode of ... -
Separation of measured noise coherence matrix into Toeplitz and Hankel parts
(CMRE, 2017/08)The cross-spectral density of ocean ambient noise is usually estimated from the product of the complex hydrophone signals, each of which already corresponds to the summed responses of sources from all angles. The true ... -
JANUS-based services for operationally relevant underwater applications
(CMRE, 2017/11)This paper presents the design, test, and experimentation at sea of four JANUS-based services for operationally relevant underwater applications: 1) first contact and language switching; 2) transmission of automatic ... -
A distributed ID assignment and topology discovery protocol for underwater acoustic networks
(CMRE, 2017/11)This paper presents a new protocol to self assign node IDs in an Underwater Acoustic Network (UAN). The proposed solution, termed DIVE for Distributed Id assignment and topology discoVEry, is fully distributed and ... -
A data-driven control strategy in synergy with continuous active sonar for littoral underwater surveillance
(CMRE, 2017/11)In this work, we describe a data-driven Mission Management Layer (MML) running on-board AUVs which manages the phases of a littoral surveillance mission and exploits the characteristics of Continuous Active Sonar (CAS) ... -
Joint probabilistic data association tracker for extended target tracking applied to X-band marine radar data
(CMRE, 2017/11)X-band marine radar systems are flexible and low-cost tools for monitoring multiple targets in a surveillance area. Although they may suffer from several sources of interference, e.g., sea clutter, they can provide ...