Browsing Technical Reports by Title
Now showing items 137-156 of 322
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High-resolution beamforming techniques performance analysis
(NATO. SACLANTCEN, 1986/11)Seven different beamforming techniques (including both conventional and high-resolution types) have been analyzed and compared in order to develop a quantitative relationship between resolution performance on the one hand ... -
High-resolution characterization of shallow water sea bottom: need and methodology for a ground-truth reference database
(NATO. SACLANTCEN, 1994/12)A systematic approach to underwater observation of high-resolution seabed features has been developed. These include: morphology caused by current, wave, and biological factors and certain engineering geological factors ... -
Horizontal array gain in shallow water
(NATO. SACLANTCEN, 1980/12)Some results of a comprehensive model study on the use of horizontal hydrophone arrays in shallow water are presented. Well-known signal processing techniques are applied to a shallow-water sound propagation model in order ... -
Hydrographic measurements in the southern Iceland and Norwegian Seas during June and August, 1989
(NATO. SACLANTCEN, 1993/12)This memorandum documents an extensive collection of CTD data made during two cruises in the region between Greenland and Norway -
Hydrography of the Iceland-Faeroe Ridge during March 1992: environmental data during NORDIC 92
(NATO. SACLANTCEN, 1992/12)This memorandum documents an extensive collection of CTD and XBT data made on the Iceland-Faeroe Ridge in March, 1992 by the SACLANTCEN vessel Alliance and the FWG vessel Planet as part of a larger operation called NORDIC ... -
Icelandic current experiment GIN Sea Cruise 88 data report: Hydrography and circulation: volume 1
(NATO. SACLANTCEN, 1992/09)The hydrographic and circulation data from the GIN '88 cruise on board the R/V Alliance are summarised in this data report. This cruise constituted the first component of the Icelandic Current Experiment, an observational ... -
Icelandic current experiment GIN Sea Cruise 88 data report: Hydrography and circulation: volume 2
(NATO. SACLANTCEN, 1992/09) -
Impact of uncertain environmental knowledge on the shallow-water transfer function
(NATO. SACLANTCEN, 1992/12)It is assumed that the acoustic channel can be modeled as a linear time-invariant space-variant filter. In this case, from linear systems theory, it is known that the filter output, that is the predicted source signal ... -
Improvements to data networks in support of REA during Generic Oceanographic Array Technology (GOATS) 98
(NATO. SACLANTCEN, 2000/05) -
Impulse response of a layered bottom
(NATO. SACLANTCEN, 1967/01)Numerical methods are used for the Fourier inversion of the frequency-dependent loss transfer function. Because of the non-zero finite values of the integrand for an infinite high frequency, the asymptotic value is subtracted ... -
Infrared detection of marine mammals
(NURC, 2005/12)An infrared (IR) binocular, designed for in-the-field military applications, was tested using in situ marine mammals during the Mar Ligure Joint Experiment 2003 (MLJX03) that took place in August-September 2003 onboard the ... -
Instrumentation for crosshole geoacoustic measurements in unconsolidated sediments
(NATO. SACLANTCEN, 1994/06)Research tools are described that enable direct measurements of sediment properties as a function of depth in unconsolidat,ed sediments. The first tool is a hole making device that sits on the sea floor and utilizes pneumatic ... -
Interface-wave propagation studies: an example of seismo-acoustic propagation in non-homogeneous materials
(NATO. SACLANTCEN, 1990/01)This study addresses the problem relating to the interaction processes -
Interpretation and fusion of sonar images using evidential reasoning
(NATO. SACLANTCEN, 1995/12)A method and system architecture for automatic interpretation and fusion of multiple sonar images is proposed. The interpretation of a sonar image consists of the creation of a symbolic geographical map indicating the ... -
Interpretation and representation of the synoptic features in the Iceland-Faeroe-Shetland region
(NATO. SACLANTCEN, 1993/07)The kinematic structure of the sub-inertial fluctuations of measured current and temperature fields from 6 moorings deployed during the June -
Inverse acoustical determination of photosynthetic oxygen productivity of Posidonia seagrass
(NATO. SACLANTCEN, 2000/02)As part of geoacoustic inversion experiments (Yellow Shark) in the Giglio basin, off the west coast of Italy, low frequency, broad-band propagation measurements were performed in the winter and spring of 1995 over a dense ... -
Inversion for geometric and geoacoustic parameters in shallow water: experimental results
(NATO. SACLANTCEN, 1994/12)Experimental results on the estimation of both geometric and geoacoustic parameters in shallow water are presented. Genetic algorithms are used for estimation of the forward model parameters, the -
Inversion of broad-band multitone acoustic data from the YELLOW SHARK summer experiment
(NATO. SACLANTCEN, 1997/09)Integral geoacoustic properties of the sea bottom were determined from full-field inversion of broad-band, waterborne, acoustic propagation data. The data were obtained during the YELLOW SHARK 94 experiment along a 15-km ... -
Inversion of seismo-acoustic data using genetic algorithms and 'a posteriori' distributions
(NATO. SACLANTCEN, 1993/08)The goal of many underwater acoustic modelling problem is to establish the physical parameters of the environment. With the increase in -
Inversion of seismo-acoustic real data using genetic algorithms
(NATO. SACLANTCEN, 1994/03)An inversion scheme for the estimation of the physical parameters
