Browsing Technical Reports by Title
Now showing items 291-310 of 322
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The GIN Sea: Review of physical oceanography and literature from 1972
(NATO. SACLANTCEN, 1988/07)A synthesis and review of the physical oceanography of the GIN Sea (Greenland, Iceland, and Norwegian Seas) is presented. An accompanying bibliography complete from 1972 is included. Emphasis is placed on describing the ... -
The influence of a low velocity layer on the reflectivity from the sea floor
(NATO. SACLANTCEN, 1966/05)The influence on the reflectivity of a low velocity layer on top of a sand half-space has been investigated. By expressing sediment density and velocity in terms of porosity it has been possible to use this quantity as an ... -
The influence of fluctuations in acoustic travel time on locating the position of an underwater sound source
(NATO. SACLANTCEN, 1985/10)This paper investigates the accuracy of an underwater acoustic positioning system in locating a sound source that transmits at unknown times in conditions in which the acoustic travel times between -
The influence of quantizing and sampling on the signal-to-noise ratio of a complex correlator
(NATO. SACLANTCEN, 1967/09)The combined effects of sampling and phase-quantizing of phase- modulated signals in Gaussian noise are studied and expressed in terms of the output signal-to-noise ratio of a matched filter correlator. The obtained results ... -
The joint SACLANTCEN/USA towed vertically directive source - TVDS
(NATO. SACLANTCEN, 1996/07)This report is the text of a paper presented at Undersea Defence Technology, Cannes, 1995 (UDT 95). It outlines the development of the Towed Vertically Directive Source (TVDS) and the associated ship-handling and winching ... -
The KRAKEN normal mode program
(NATO. SACLANTCEN, 1991/09)In the late 1970's several normal-mode models existed which were -
The magnetic dipole moment of RV Alliance
(NATO. SACLANTCEN, 1999/02)A SACLANTCEN magnetometry sea trial was performed in September 1998 in the northern Tyrrhenian Sea in the vicinity of the Formiche di Grosseto islands. One of the trial objectives -
The Ninth International Conference on Information Fusion (Fusion 2006) final conference report
(NURC, 2006/10)The 9th International Conference on Information Fusion (FUSION 2006) was held on 10-13 July 2006 in Florence, Italy. The FUSION conference series serves as the annual gathering and -
The ocean wave dynamo: a source of magnetic ambient noise
(NATO. SACLANTCEN, 1997/09)The electromagnetic dynamo field of sea surface waves, a consequence of the Lorentz force, has been measured with two simultaneously operating, closely spaced tri-axial magnetometers. Measurements from a magnetometer located ... -
The propagation and reception of transient electromagnetic signals in the presence of a conducting half-space
(NATO. SACLANTCEN, 1961/05)In this paper a theoretical treatment is given of the short-distance propagation and reception of a step-function in the presence of a conducting half-space. The step-function is generated by a horizontal electric dipole ... -
The reverberation of sound from smooth ocean floors
(NATO. SACLANTCEN, 1963/02)The reverberations produced by a completely flat surface separating two homogeneous isotropic fluids is investigated. There is no effort to include the effect of rough surfaces which would be a logical extension of the ... -
The SACLANTCEN sphincter corer assembly = Carottier a sphincter du SACLANTCEN: part 1: a wide-diameter corer with waterproof core-catcher: part 2: an electrical engineering system
(NATO. SACLANTCEN, 1965/03)A long, wide-diameter corer with a waterproof core-catcher is described in Part I. Its design is closer to theoretically ideal proportions than most oceanographic corers, and the cores it provides appear to be unmodified ... -
The sea surface as a random filter for underwater sound waves
(NATO. SACLANTCEN, 1974/06)In this dissertation the phenomenon of scattering and reflection of underwater sound waves from the sea surface is studied by considering the surface sound channel as a random, time-dependent filter. This filter can be ... -
The sub-bottom structure of the Gulf of La Spezia
(NATO. SACLANTCEN, 1968/12)The sub-bottom structure of the Gulf of La Spezia, Italy, has been investigated by continuous seismic profiling and sediment coring. The seismic profiles were used to develop contour plots of sub-bottom layers, which were ... -
The temperature structure in the upper layers of the Ligurian Sea and its seasonal variations
(NATO. SACLANTCEN, 1962/05)Water temperature measurements in the Ligurian Sea down to depths of 150 meters and meteorological data connected with these measurements for the period July 1960 to October 1961 are presented in the form of graphs and ... -
The temperature structure in the upper layers of the Ligurian Sea and its seasonal variations: supplement to SACLANTCEN technical report no. 8
(NATO. SACLANTCEN, 1964/04)Water temperature measurements, down to depths of 150 meters, and metereological data connected with these measurements carried out in t 1e Ligurian Sea in May and November 1962, are presented in the form of graphs and ... -
Time series variability in fluctuating ocean waveguides
(NATO. SACLANTCEN, 1999/07)The variability of signals propagating through an uncertain sound speed structure is addressed. Signals are assumed to travel in a narrow band adiabatically in modes and to experience fluctuations in sound speed which are ... -
Time-evolution modelling of seafloor scatter: Part 1: Theory
(NATO. SACLANTCEN, 1997/04)A time-series model for acoustic seafloor backscattering is described. -
Time-evolution modelling of seafloor scatter: Part 2: experimental verification
(NATO. SACLANTCEN, 1997/04)A time-evolution model of seafloor scatter is numerically implemented and experimentally verified. The model is based on expressing analytically the elementary time-backscattered response of every seafloor surface and every ... -
Toeplitz constrained adaptive beamforming with auxiliary data
(NATO. SACLANTCEN, 1997/02)Submarine and mine detection using active sonar face similar problems when adaptive beamforming is required to provide high angular resolution or to suppress angularly isolated interferences. Both