Browsing Reprints by Title
Now showing items 401-420 of 548
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Regional reflection seismic exploration of the Strait of Sicily
(NATO. SACLANTCEN, 1972/09)A regional seismic reflection survey was performed by OGS in 1970 on the Sicily Channel, using multichannel digital techniques and flexotir source. Reflections up to about 5 s (two-way time) have been obtained. The analysis ... -
Relating in situ shear wave velocity to void ratio and grain size for unconsolidated marine sediments
(NATO. SACLANTCEN, 1997)Recent advances in field hardware have meant that it has become possible to measurein situ shear wave velocity in the upper few decimetres of sea floor sediment in a routine manner. It is known that shear wave velocity can ... -
Relative contribution of surface roughness and bottom attenuation to propagation loss in shallow water
(NATO. SACLANTCEN, 1975/10)A simulation study has been performed to investigate the relative importance of the contributions of surface roughness and bottom attenuation to propagation loss under differing environmental conditionso The NRL normal ... -
A relocatable EnKF ocean data assimilation tool for heterogeneous observational networks
(CMRE, 2019/06)This study investigates the performance of a multivariate Ensemble Kalman Filter coupled with a relocatable limited-area configuration of the Regional Ocean Modeling System to predict ocean states by assimilating a ... -
Results from the use of broad-band, sub-bottom seismic data with statistically based sediment classification techniques
(NATO. SACLANTCEN, 1997)The QTC VIEW sediment classification system has been applied to shallow, high resolution seismic data recorded with the IKB-SEISTEC profiler from the navigable channel of the St. Lawrence estuary in Canada. A number of 10 ... -
Retrodirective array performance case studies and implications for mine countermeasures
(NATO. SACLANTCEN, 1997)The use of focused acoustic fields for the mechanical destruction of fluid-borne targets is applied zn. the medical field for the comminution of kidney stones by lithotripsy. Inhomogeneities in the propagation medzum are ... -
Review of numerical models in underwater acoustics including recently developed fast-field program
(NATO. SACLANTCEN, 1984/12)Two papers given by SACLANTCEN personnel at the NATO Advanced Research Workshop on Hybrid Formulation of Wave Propagation and Scattering at Castel Gandolfo, Rome, Italy on 30 August to 3 September 1983 are published as a ... -
Review of target strength information for waterside security applications
(NURC, 2008)Estimates of the target strength of objects, such as for example scuba tanks and swimmer delivery vehicles, are parameters of interest in all phases of the design of waterside security systems. Results of numerical target ... -
Riverine environmental acoustics at an ocean estuary
(NATO. SACLANTCEN, 1997)The purpose of these studies was to investigate some of the more important geoacoustrc parameters that might govern the use of high frequency sonar in muddy rivers, where they flow into the sea. Both environmental and ... -
A robust, opportunistic clock synchronization algorithm for ad hoc underwater acoustic networks
(CMRE, 2019/06)The proliferation of deployed sea-going autonomous platforms, such as autonomous underwater vehicles (AUVs), unmanned surface vehicles (USV), and sensor nodes anchored to the seabed, makes the deployment of true underwater ... -
Role of propagation in ambient noise
(NATO. SACLANTCEN, 1982/06)To be useful for modern ASW systems design and analyses, descriptions of ambient noise fields must go beyond average omnidirectional spectra and include horizontal and vertical patterns, fluctuations with time, dependencies ... -
SACLANTCEN real-time signal processing system
(NATO. SACLANTCEN, 1979/12)To meet its increasing requirements in real-time signal processing, SACLANTCEN has developed a general purpose. signal processing system called WARP to be uS.ed with a fairly wide range of underwater acoustic research ... -
Scalable adaptive multitarget tracking using multiple sensors
(CMRE, 2019/06)In networked mobile multitarget tracking systems, parameters such as detection probabilities, clutter rates, and motion model parameters are often unknown and time-varying. Such parameter variability can seriously degrade ... -
A scalable algorithm for tracking an unknown number of targets using multiple sensors
(CMRE, 2019/06)We propose an algorithm for tracking an unknown number of targets based on measurements provided by multiple sensors. Our algorithm achieves low computational complexity and excellent scalability by running belief propagation ... -
Scalable and distributed sea port operational areas estimation from AIS data
(CMRE, 2019/06)Seaports are spatial units that do not remain static over time. They are constantly in flux, evolving according to environmental and connectivity patterns both in size and operational capacity. As such any valid decision ... -
Scalable distributed change detection and its application to maritime traffic
(CMRE, 2019/06)Building on a novel methodology based on the Ornstein-Uhlenbeck (OU) process to perform accurate long-term predictions of future positions of ships at sea, we present a statistical approach to the detection of abrupt changes ... -
Scattering from a random interface
(NATO. SACLANTCEN, 1975/10)The problem of scattering from a random interface separating two fluids with different densities and sound speeds is considered. The method is to write coupled integral equations in coordinate space connecting the surface ... -
Scattering from an elastic cylinder buried beneath a rough water/sediment interface
(NATO. SACLANTCEN, 1997)In this paper a plane-wave decomposition method is used to compute the two-dimensional backscattering from a buried elastic cylinder as a function of frequency. The cases of a pat water/sediment interface and deteministically ... -
Scoring robotic competitions: balancing judging promptness and meaningful performance evaluation
(CMRE, 2019/05)To have a significant and fair competition an adequate scoring system is necessary. Different scoring systems exist, each one directly related to the nature and goals of the competition, e.g. student/educational, focused ... -
Seabed characterization by inversion of parametric sonar data: selection of the cost function
(NATO. SACLANTCEN, 1997)A class of possible cost functions to be used in model-based estimation of bottom parameters from highfrequency backscatter signals is introduced. The cost is based on the properttes of the signal in the wavelettransformed ...