Browsing by Type "Scientific Technical reports (TR)"
Now showing items 21-40 of 40
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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 ... -
Magnetic, gravity and depth surveys in the Mediterranean and Red Sea
(NATO. SACLANTCEN, 1965/04)This report is a copy of a paper published in Nature, Vol. 204, 4965, 1964: 1245-1248 by T.D. Allan of this Centre, H. Charnock of this Centre at the time of the surveys but now of the National Institute of Oceanography, ... -
New mechanical equipment for handling oceanographic cables
(NATO. SACLANTCEN, 1964/04)The four pieces of equipment described in this report have been designed to facilitate the handling of oceanographic cables by replacing the heavy, and often expensive, equipment at present in use, with lighter, less ... -
Observed sound velocity and temperature profiles in the Strait of Gibraltar during the passage of an internal wave
(NATO. SACLANTCEN, 1966/10)Sound velocity and temperature measurements taken from the sea-surface to 350 m depth, close to one spot over a 24-hour period revealed the passage of an internal wave of approximately 60 m amplitude. The effect of this ... -
On the recording of low frequency signals on magnetic tape
(NATO. SACLANTCEN, 1962/01)A short review of the different methods of recording on magnetic tape is given together with the advantages and disadvantages of each method. Particular emphasis was given to the ability to record low frequencies. This ... -
Parametric relations on FM sonar
(NATO. SACLANTCEN, 1961/06)The report deals with the simple theory of FM sonar operations and shows how an optimum system may be designed. It also indicates the effects of doppler, the equipment and other factors which may be expected, in practice, ... -
Principles and methods of core analysis at the SACLANT ASW Research Centre
(NATO. SACLANTCEN, 1967/08)The methods and accuracy of measuring core parameters at the SACLANTCEN are described. Those for measuring sound velocity and electrical resistivity are explained in detail. -
Problems of pursuit and evasion
(NATO. SACLANTCEN, 1966/06)Problems of pursuit and evasion play significant part in naval warfare - particularly in ASW. They are of no less importance in aerial warfare and are now becoming important in space. Their practical importance has given ... -
Short-period vertical displacements of the upper layers in the Strait of Gibraltar: part 1 - text: part 2 - diagrams
(NATO. SACLANTCEN, 1964/11)The report is principally based on observations of short-term displacements made by the author in the summers of 1958, 1959, and 1961, using a thermistor chain. Pilot tubes installed on the thermistor chain made simultaneous ... -
Simple instrumentation for measuring temperature gradients at the sea-air interface, including the results of Winter 1964/65 measurements
(NATO. SACLANTCEN, 1965/07)Very little information is available on the temperature differences in the first several centimetres of air above the sea surface and the first few centimetres of water below the sea surface. Data of this kind are important ... -
Some acoustical characteristics of underwater explosions of hydrogen-oxygen mixtures
(NATO. SACLANTCEN, 1963/02)The acoustic characteristics of a hydrogen-oxygen explosive mixture are investigated in an attempt to find a substitute for solid explosives (e.g. TNT) which will achieve a simple underwater acoustic pulse uncomplicated ... -
Sound attenuation between 200 and 10,000 cps measured along single paths
(NATO. SACLANTCEN, 1965/09)In the deep Mediterranean basins, the water is perfectly isothermal below 400 m, and the deep refracted ray gives clear signals up to 40 km, with a spreading loss free from any frequency-dependent effect. Exploiting this ... -
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 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 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 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 ...