Browsing by Title
Now showing items 150-169 of 882
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Application of real data to sonar detection by neural networks
(NATO. SACLANTCEN, 1992/11)This memorandum describes the results of applying an artificial neural network for the detection of target echoes. The present study is a continuation of work conducted in 1989 in which a three-layer artificial neural ... -
Application of the Riesz potential to the Cauchy problem for wave propagation in an inhomogeneous medium
(NATO. SACLANTCEN, 1971/12)The method of Riesz [Ref. l] for the solution of hyperbolic partial differential equations is applied to the Cauchy problem for the wave equation. It is shown that the first term in the Riesz potential function, which is ... -
Approximate methods for ray tracing
(NATO. SACLANTCEN, 1971/12) -
Arctic ambient noise statistical measurement results and their implications to sonar performance improvements
(NATO. SACLANTCEN, 1982/06)Recent analyses of FRAM II arctic data have shown that under ice ambient noise can be at times highly impulsive and non-Gaussian. The analyses included time domain statistical measurements which were consistent with ... -
Areal seabed classification using backscatter angular response at 95kHz
(NATO. SACLANTCEN, 1997)A sediment classification scheme is developed based on the angular response (AR) of the seabed backscatter strength. The AR is characterised based on its mean level and slope over predefined angular sectors, and the presence ... -
Array and cable tracking data through ship maneuvers
(NATO. SACLANTCEN, 1993/08)This paper presents tracking results from two sea tests in which a towed cable and array were tracked at the Atlantic Undersea Test and Evaluation Center (AUTEC). The tracking tests involved instrumenting the cable with ... -
Array performance and variability at short range near Vestfjorden
(NATO. SACLANTCEN, 1993/08)An experiment was conducted in October 1989 in shallow water near Vestfjorden in support of low frequency active sonar system research at SACLANTCEN. This report addresses some acoustic measurement results from that test ... -
Array shape determination with a real-time model
(NATO. SACLANTCEN, 1993/08)A shape estimation scheme based on precomputed frequency-domain solutions of array motion is presented. The boundary conditions supporting each solution are discrete Fourier transform (OFT) components of sensor measurements, ... -
Arrays and array processors: future real time applications in oceanography and sonar
(NATO. SACLANTCEN, 1979/12)In the last several years oceanographic applications of arrays have increased substantially. The spatial resolution and redundancy provided by arrays have been necessary in the interpretation of signal propagation in complex ... -
Assessment of sea wave spectra using a surfaced glider
(CMRE, 2019/06)The determination of non-directional and directional sea wave spectra is attempted by analysing the dynamical response of a surfaced Slocum glider. The method makes use of the glider heave motion to infer non-directional ... -
Assessment techniques for computer models of sound propagation
(NATO. SACLANTCEN, 1975/10)Computer models of sound propagation have exactly three drawbacks: the model only approximates reality,the computer program only approximates the model, and the cost approximates infinity. The only way to assess these ... -
Assimilation of hydrographic data from the Atlantic inflow experiment into ocean models
(NATO. SACLANTCEN, 1989/10)This study represents the link between observational and numerical programs. A method for data -
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 ... -
At-sea measurements of diver target strengths at 100 Khz: measurement technique and first results
(NURC, 2006/08)During a recent at-sea trial of a diver detection system, the opportunity was taken of developing a technique for in-situ measurement of diver target strengths. The technique was based on making the diver perform circular ... -
Atlantic inflow experiment GIN Sea Cruise'87 datareport: Part I: Tydeman hydrography: volume 1
(NATO. SACLANTCEN, 1991/12)The hydrographic data from the GIN 87-T cruise on board the HNLMS Tydeman are summarised in this data report. This cruise constituted the first cruise of the 1987 portion of the Atlantic Inflow Experiment, -
Atlantic inflow experiment GIN Sea Cruise'87 datareport: Part I: Tydeman hydrography: volume 2
(NATO. SACLANTCEN, 1991/12) -
Atlantic inflow experiment GIN Sea Cruise'87: Data report Part II: Circulation (Faeroe Channel)
(NATO. SACLANTCEN, 1991/12)This data report summarizes results of the Atlantic Inflow Experiment, -
Atlantic inflow experiment, GIN Sea Cruise'86: Data report Part II: circulation
(NATO. SACLANTCEN, 1990/03)As the initial field effort of the Atlantic Inflow Experiment, three instrumented moorings were deployed in the Faeroe-Shetland Channel during June 1986. The purpose of the array was to monitor the inflow, and to tract the ... -
Atlantic inflow experiment, GIN Sea cruise'86: Data report: Part I: Hydrography + (Appendixes B and C)
(NATO. SACLANTCEN, 1988/06)An investigation of the inflow of North Atlantic surface water into the Greenland-Norwegian-Iceland -
Attenuation of shear waves in near-surface sediments
(NATO. SACLANTCEN, 1997)In situ measurement of compressional and shear speed and compressional attenuation in near-surface marine sediments is a well-developed technology but techniques required to measure shear attenuation have lagged behind. ...