Browsing Reprints by Title

Now showing items 367-386 of 548

    • Performance evaluation of underwater medium access control protocols: at-sea experiments 

      Petroccia, Roberto; Petrioli, Chiara; Potter, John Robert (CMRE, 2019/06)
      In this paper, we investigate the performance of three medium access control (MAC) protocols (CSMA, TLohi, and DACAP) representing simple, intermediate, and fully negotiated protocols, to access the underwater acoustic ...

    • Performance of three averaging methods for various distributions 

      Nuttall, Albert H. (NATO. SACLANTCEN, 1982/06)
      The performance of three averaging methods, namely the sample median, the sample arithmetic mean, and the sample geometric mean, are analyzed in tenns of their bias, variance, and mean square error. The bias and variance ...

    • Physical and dynamical characteristics of a 300 m-deep anticyclonic eddy in the Ligurian Sea (Northwest Mediterranean Sea): evidence from a multi-platform sampling strategy 

      Borrione, Ines; Falchetti, Silvia; Alvarez, Alberto (CMRE, 2019/06)
      We describe the physical and dynamical characteristics of a mesoscale anticyclonic eddy observed in August 2013 over the shelf-break region of the northeastern sector of the Ligurian Sea, between the northeastern edge of ...

    • Physics of bottom scattering and some applications 

      Gensane, Marc (NATO. SACLANTCEN, 1997)
      The main bottom scattering theories are described in their bistatic formulation: composite-roughness, and volume scattering. Several applications are proposed. One of the main concerns is to check the mono- and bisfafic ...

    • pOctaver, adding scripting language to MOOS 

      Vermeij, Arjan; Pastore, Thomas J. (NURC, 2010/08)
      NURC uses MOOS-IvP in a scientific research and rapid prototyping environment. Contributions to the open-source suite of MOOS-IvP software is readily made by programmers adept at C++ programming. However, the utility of ...

    • Position and shape of the surface shadow zone 

      De Raigniac, Bernard (NATO. SACLANTCEN, 1971/12)
      From surface reverberation studies conducted by SACLANTCEN's Target Classification Group"C , it has been found necessary to know before any sea experiment the precise position of the first surface shadow zone. Since normal ...

    • Practical active sonar receiver systems using fast frequency-domain correlation 

      Curtis, T. E.; Webb, A. B. (NATO. SACLANTCEN, 1993/08)

    • Prediction of rendezvous in maritime situational awareness 

      Uney, Murat; Millefiori, Leonardo; Braca, Paolo (CMRE, 2019/05)
      In this work, we consider the problem of algorithmically predicting rendezvous among vessels based on their trajectory forecasts in a maritime environment. The problem is treated as hypothesis testing on the expected value ...

    • Preliminary results of current measurements in the Strait of Sicily in May 1970 

      Molcard, Robert (NATO. SACLANTCEN, 1972/09)
      During May 1970, series of oceanographic observations were made in the Strait of Sicily in support of MILOCMED. Sections of hydrologic stations were made using temperature salinity recorder (TDS) and Nansen bottles by R/ ...

    • Processing of broadband acoustic signals 

      Hovem, Jens M. (NATO. SACLANTCEN, 1972/05)

    • Propeller leading edge trimming and maintenance effects on ship's noise operational performance 

      Accardo, Lucio; Baù, F. (NATO. SACLANTCEN, 1985/01)
      In the last ten years, considerable experience has been gathered at CEIMM's cavitation tunnel (Centra Esperienze Idrodinamiche Marina Militare) on the effects of propeller leading edge geometry on cavitation (and noise) ...

    • Protection in ports: countering underwater intruders 

      Kessel, Ronald T. (NURC, 2007/10)
      The advance of new capability depends on many things: the state of the art in technology, the clarity of the mission and requirements, the knowledge of the threat, the means of response, and, for developers, the state of ...

    • Random temperature structure as a factor in long-range propagation 

      Del Balzo, Donald R.; Moseley, W. B. (NATO. SACLANTCEN, 1975/10)
      A statistical description of horizontal thermal microstructure in anosotropic turbulence is developed for application with an existing acoustic propagation theory. The model predicts a temperature power density spectrum ...

    • Range and depth estimation by line arrays in shallow water 

      Klemm, Richard (NATO. SACLANTCEN, 1982/01)
      In shallow water sound propagates in terms of normal modes. The interference between the modes can be utilized to estimate range and depth of an acoustic source in shallow water by applying high resolution power estimators ...

    • Range estimation of cetaceans with compact volumetric arrays 

      Zimmer, Walter M. X. (CMRE, 2014/01)
      Passive acoustic monitoring is the method of choice to detect whales and dolphins that are acoustically active and to monitor their underwater behaviour. The NATO Science and Technology Organization Centre for Maritime ...

    • Range-dependent normal modes in underwater sound propagation 

      Graves, Ronald D.; Nagl, Anton; Uberall, Herbert M.; Haug, Anton J.; Zarur, George L. (NATO. SACLANTCEN, 1975/10)
      Normal mode theory is best suited for the case of stratified media. Range dependence of the medium properties and of its boundary may nevertheless be taken into account in the framework of an adiabatic approximation provided ...

    • Ray convergence in a flux-like propagation formulation 

      Harrison, Chris H. (CMRE, 2014/01)
      The energy flux formulation of waveguide propagation is closely related to the incoherent mode sum, and its simplicity has led to development of efficient computational algorithms for reverberation and target echo strength, ...

    • Ray tracing on a mini-computer 

      Thompson, Martin; Wijmans, Willem (NATO. SACLANTCEN, 1971/12)
      It would appear that most people engaged in solving problems in ray- tracing, use programs written for large computers . These machines commonly have large memory sizes, fast cycle times and large word length 0 This paper ...

    • Ray tracing on a mini-computer 

      Thompson, Martin; Wijmans, Willem (NATO. SACLANTCEN, 1972/05)
      It would appear that most people engaged in solving problems in ray- tracing, use programs written for large computers. These machines commonly have large memory si~es, fast cycle times and large word length . This paper ...

    • Rays and statistical diffraction theory 

      Clarke, Richard H. (NATO. SACLANTCEN, 1971/12)
      A method of extending ray tracing is proposed, such that mediumscale irregularities of a statistical nature are taken into account along with large-scale irregularities in refractive index of the medium.