Wyniki wyszukiwania dla: PROPAGATION IN THE SHALLOW SEA

• Propagation of Acoustic Disturbances in Shallow Sea

  Publikacja

  • E. Kozaczka

  - Rok 2013

  Propagation of acoustic waves in shallow sea differs fundamentally from the same phenomenon occurring in deep sea in view of non-negligible distance from the sea bottom in the first case, where presence of two regions limiting the water layer results in the acoustic pressure distribution induced by a harmonic source has an interferential nature as a result of multi-path propagation of the acoustic signal. These interferential properties...

• Propagation of Ship-Generated Noise in Shallow Sea

  Publikacja

  • E. Kozaczka
  • G. Grelowska

  - Polish Maritime Research - Rok 2018

  Contamination of sea environment by noise and any energy radiated to water constitutes today a problem to which more and more attention is paid, in view, a.o., of consequences of an impact of these factors onto marine fauna. European Union has introduced a directive by which EU countries are made responsible to undertake efforts aimed at reaching a good envirenmental status of European seas by 2020. A main source of underwater...

  Pełny tekst do pobrania w portalu

• Theoretical Model of Acoustic Wave Propagation in Shallow Water

  Publikacja

  • E. Kozaczka
  • G. Grelowska

  - Polish Maritime Research - Rok 2017

  The work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...

  Pełny tekst do pobrania w portalu

• Shipping Low Frequency Noise and Its Propagation in Shallow Water

  Publikacja

  • E. Kozaczka
  • G. Grelowska

  - ACTA PHYSICA POLONICA A - Rok 2011

  One of the most significant factor influencing acoustical climate of the sea is underwater noise generated by moving ships. If the considered sea area has features of the shallow water, namely the wave frequency fulfils relation f < 10c/h, where c denotes phase speed of sound, and h is depths of the sea, then in certain distance from the wave source specific image of sound pressure distribution in the mean of wave modes appears....

  Pełny tekst do pobrania w portalu

• The shallow sea experiment with usage of linear hydrophone array

  Publikacja

  • G. Grelowska
  • E. Kozaczka
  • I. Gloza
  • S. Kozaczka

  - Rok 2013

  Purpose of this article is to present designed and made linear hydrophone array and the results obtained during in situ trails on Gulf of Gdańsk. The measuring system allowed to localize hydrophones in the selected points and perform measurements in both the horizontal antenna positioning and vertical. Made in this way recordings allow creating accurate 3D imaging of sound intensity/propagation. During research three floating objects...

  Pełny tekst do pobrania w serwisie zewnętrznym

• UNDERWATER NOISE GENERATED BY A SMALL SHIP IN THE SHALLOW SEA

  Publikacja

  • G. Grelowska
  • E. Kozaczka
  • S. Kozaczka

  - Archives of Acoustics - Rok 2013

  Study of the sea noise has been a subject of interest for years. The first work of this scope were published at the turn of the twentieth century by Knudsen (KNUDSEN et al., 1948) and G. Wenz (WENZ, 1962). Disturbances called "shipping noise" are one of the important components of the sea noise. In this work the results of an experimental research of underwater noise produced by a small ship of a classic propulsion are...

  Pełny tekst do pobrania w portalu

• Some aspects of noise generated by a small ship in the shallow sea

  Publikacja

  • G. Grelowska
  • E. Kozaczka
  • W. Szymczak
  • S. Kozaczka

  - Rok 2012

  The passing and underwater moving objects produce the noises of variable intensity, which significantly increase the overall level of noise in the sea. This applies to both the sonic and ultrasonic range. The excessive levels of underwater noise adversely affects the so-called underwater acoustic climate and is the reason why this phenomenon is intensively investigated from the number of years. The results of experimental work...

  Pełny tekst do pobrania w serwisie zewnętrznym

• Nonlinear principal component analysis of the tidal dynamics in a shallow sea

  Publikacja

  • A. Herman
  • A. Herman

  - GEOPHYSICAL RESEARCH LETTERS - Rok 2007

  Pełny tekst do pobrania w serwisie zewnętrznym

• Upwelling intrusion into shallow Puck Lagoon, a part of Puck Bay (the Baltic Sea)

  Publikacja

  • M. Matciak
  • J. Nowacki
  • W. Krzymiński

  - OCEANOLOGICAL AND HYDROBIOLOGICAL STUDIES - Rok 2011

  Pełny tekst do pobrania w serwisie zewnętrznym

• Wind-wave variability in a shallow tidal sea—Spectral modelling combined with neural network methods

  Publikacja

  • A. Herman
  • R. Kaiser
  • H. Niemeyer

  - COASTAL ENGINEERING - Rok 2009

  Pełny tekst do pobrania w serwisie zewnętrznym