HYDROACOUSTICS - Czasopismo - MOST Wiedzy

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HYDROACOUSTICS

ISSN:

1642-1817

eISSN:

2450-128X

Wydawca:

Polska Akademia Nauk , Polskie Towarzystwo Akustyczne

Punkty Ministerialne: Pomoc

Punkty Ministerialne - aktualny rok
Rok Punkty Lista
Rok 2024 5 Czasopisma spoza wykazu ministerialnego 2024
Punkty Ministerialne - lata ubiegłe
Rok Punkty Lista
2024 5 Czasopisma spoza wykazu ministerialnego 2024
2023 5 Czasopisma spoza wykazu ministerialnego 2023
2022 5 Czasopisma spoza wykazu ministerialnego (2019-2022)
2021 5 Czasopisma spoza wykazu ministerialnego (2019-2022)
2020 5 Czasopisma spoza wykazu ministerialnego (2019-2022)
2019 5 Czasopisma spoza wykazu ministerialnego (2019-2022)
2018 7 B
2017 7 B
2016 6 B
2015 6 B
2014 7 B
2013 7 B
2012 4 B
2011 4 B
2010 6 B

Model czasopisma:

Open Access

Impact Factor:

brak danych

Polityka wydawnicza:

Licencja: CC BY-NC-SA 3.0
Licencja
Creative Commons: BY-NC-SA 3.0 otwiera się w nowej karcie
Informacja o polityce wydawniczej
brak danych
Informacja o warunkach samoarchiwizacji
Zawarta w licencji
Czy czasopismo pozwala na samoarchiwizację
Tak - z ograniczeniami
Submitted Version Pomoc
tak
Accepted Version Pomoc
tak
Published Version Pomoc
tak
Miejsca samoarchiwizacji
poza serwisami komercyjnymi
repozytorium publikacji naukowych
strona pracodawcy (zgodnie z afiliacją)
strona domowa autora
Informacje o polityce dot. danych badawczych
brak danych
Embargo w miesiącach
brak embargo
Informacje dodatkowe
Przy udostępnianiu / rozpowszechnianiu należy podać źródło oryginału.
Typ licencji podany przy artykule: CC BY-NC-SA 3.0.

Filtry

wszystkich: 144

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wyczyść Filtry wybranego katalogu niedostępne

Katalog Czasopism

Rok 2013
  • A novel method of time-frequency analysis: an essential spectrogram
    Publikacja

    A novel precise method of time-frequency analysis is presented. In the algorithm, a new energy distribution is estimated by simultaneously discard or displacement of the classical spec- trogram energy. A channelized instantaneous frequency and a local group delay are used in order to replacement in the same manner as formulated by Kodera et al. [1, 2]. Additionally, new representations: a channelized instantaneous bandwidth and...

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  • APPLICATION OF SATELLITE IMAGERY AND GIS TOOLS FOR LAND SURFACE TEMPERATURE ESTIMATION AND VERIFICATION
    Publikacja

    - HYDROACOUSTICS - Rok 2013

    Land surface temperature (LST) plays an important role in many land-surface processes on regional as well on global scales. It is also a good indicator of energy flux phenomena and is used as a parameter in various Earth observation related studies. However, LST estimation based on processing and utilisation of satellite derived data constitutes several problems in terms of time limitations, accessibility, atmospheric influence...

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  • Automatic Analysis of Trajectories of Moving Objects
    Publikacja

    Ongoing monitoring is essential to providing security and safety of maritime and air operations. This paper presents the research in the area of automatic analysis of movement of unrestricted vehicles like ships and air-planes. The analysis is aimed at extraction of trajectory information, and the results can be used to identify anomalous behaviour in archived and real-time data. In this paper we focus on data acquired using the...

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  • Considerations of Adaptive Digital Communications in Underwater Acoustic Channel
    Publikacja

    Down-link communication (DLC) and air transportable communication (ATAC) buoys as well as autonomous underwater vehicles (AUV) use acoustic links for gathering oceanographic data from underwater monitoring systems. The underwater channel propagation conditions are diverse in nature and require a special adaptive approach to the communication system design. The article presents a methodology for the communication systems design,...

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  • GeoSPAR Project. Validation and selection methods of geoinformation analysis using GIS for ranking and forecasting of terrorist threats and criminal events
    Publikacja

    - HYDROACOUSTICS - Rok 2013

    The paper presents the description of work activities which have already been done within the first two stages – WorkPackage 1 and WorkPackage 2 - of the GeoSPAR Project. In such a context the general conceptual design of the GIS system and associate web service was presented and analysed. In addition, the operational and technical requirements for the GeoSPAR system have been specified and discussed; with special emphasis on system...

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  • GIS for processing multidimensional marine data in SAAS model

    Geographic Information Systems (GIS) have always been a useful tool for visualization and processing of geospatial data. However, their capabilities of analysis non-standard information such as hydroacoustic soundings has thus far been very limited. This paper proposes a general-purpose GIS which uses techniques such as OLAP, WCS and WCPS for processing of multidimensional spatio-temporal data. The versatility of the GIS is exemplified...

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  • Implementation of Contemporary Technologies in Naval Sonars Modernization
    Publikacja

    - HYDROACOUSTICS - Rok 2013

    Today’s fast technological advancement in electronics and signal processing methods makes electronic systems, including sonars, obsolete very quickly. The Polish Navy seems to be particularly affected as its ships were built in the 1970s and 1980s. Researchers at the Gdansk University of Technology have developed a methodology for modernising Navy sonars which involves the use of new electronic sub-systems and modern, bespoke methods...

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  • Implementation of the digital receiver in multibeam long-range sonar
    Publikacja

    The article presents the implementation of a digital receiver in multibeam long - range sonar. Developed by the authors of the article, the implementation was part of sonar modernisation on large Polish Navy ships. The article explains the structure of the receiver, its design details and requirements affecting the architecture. The technical solutions regarding the equipment and signal processing algorithms for determining receiving...

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  • Improving the accuracy of bearing in active sonar with cylindrical array using spectrum estimation.
    Publikacja

    The articles presents a method for improving the accuracy of bearing in multibeam sonar with a cylindrical array. Based on a known spatial spectrum estimation technique, the method has been successfully used in linear array systems. Its accuracy of bearing is satisfactory and ensures a relatively low computational effort. The article discusses certain simplifications and assumptions to adapt the spatial spectrum estimation technique...

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  • Methods of navigation in the mobile application supporting movement of the blind

    This paper presents conclusions from the last development phase of the “Voice Maps” project. Authors specify newly found available options for navigation in affordable system for the blind with all their related aspects. System uses dedicated geographical data, built-in smartphone GPS receivers and DGPS external device in order to assist blind users in their everyday travelling. Authors also discuss new methods to improve positioning...

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  • Multibaem Sonar Records Data Decimation Using Hierarchical Spline Interpolation
    Publikacja

    Multibeam sonar records feature high vertical and horizontal resolution. Interpolating and approximating, eventually displaying of of high volume scattered 3D raster data leads to some difficulties related to a computer processing power. The paper presents some advantages of using hierarchical splines in the context. Such an approach facilitates real time 3D MBS data rendering.

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  • Processing of Marine Satellite Data in WEB-BASED GIS

    GIS systems are important modern word. They allow to quickly analyse and corelate various data bound to their geographical context. The paper describes Web-base GIS with ability to integrate and analyse data from many sources such as: satellite imagery, threat simulation models, marine vessels Automatic Identification System, raster and vector topographic charts. Some details of system architecture and implementation are presented...

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  • Source-related Wavefields in Fluids and Dielectrics: A new way of Thinking about Medium Dynamics
    Publikacja

    - HYDROACOUSTICS - Rok 2013

    Acoustic and electromagnetic wave phenomena may seem to have a proper formal representation in field theory dating from the 19th century, founded on the mathematics of complex functions. This paper shows, however, that when replacing the classical spectrum-domain approach related to the assumption of harmonic timeform of signals, with a time-domain approach imposingnorestrictionastotheclassoftimeevolutionofsourceandfieldsignals,...

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  • Three-dimensional representation of geographic data in a Web-based GIS
    Publikacja

    Presenting geographic data in a web environment has been a long standing problem. For many years the low performance of web browsers has limited the visualization of spatial data to only two dimensions. More recently, the introduction of open standards for 3D acceleration of web applications sparked the emergence of new methods of presenting three-dimensional data in a web browser without using third-party extensions. However,...

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Rok 2012
  • Acoustic Processor of the Mine Countermeasure Sonar

    This paper presents the concept of an acoustic processor of the mine countermeasure sonar. Developed at the Department of Marine Electronics Systems, Gdansk University of Technology, the acoustic processor is an element of the MG-89, an underwater acoustic station. The focus of the article is on the modules of the processor. They are responsible for sampling analogue signals and implementing the algorithms controlling the measurement...

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  • Application of Maximum Lenght Sequence in Silent Sonar
    Publikacja

    Silent sonars are designed to reduce the distance over which their sounding pulses can be detected by intercept sonars. In order to meet this objective, we can use periodical sounding signals that have low power, a very long duration and wide spectrum. If used in the silent sonar's receiver, matched filtration ensures very good detection of motionless or slow moving targets. However, it is more difficult to detect echo signals...

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  • Backscattering properties of southern Baltic herring
    Publikacja

    - HYDROACOUSTICS - Rok 2012

    Reliable TS(L) relationship is required to improve acoustic algorithms of abundanceestimation of Baltic herring. The relationships, empirically obtained in different parts of theBaltic Sea, produce up to 8 dB – difference in the herring TS. In order to develop an accurateTS(L) relationship, it is important to analyze factors controlling the TS variability. Thepossible impact of the regional difference...

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  • Integration of inertial sensors and GPS system data for underwater navigation

    The Inertial Navigation System (INS) is usually employed to determine the position of an underwater vehicles, like Remotely Operated Vehicles (ROV) and, more recently, Autonomous Underwater Vehicle (AUV). The accuracy of the position provided by the INS, which uses accelerometers and gyroscopes, deteriorates with time. An external aiding sources such as the Global Positioning System (GPS) can be employed to reduce the error growth...

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  • Measurements of transmission properties of Acoustic Communication Channels
    Publikacja

    Tough transmission properties of shallow water acoustic channels (SWAC) highly limit the use of underwater acoustic communication (UAC) systems. An adaptive matching of modulation and signaling schemes to instantaneous channel conditions is needed for reliabledata communications. This creates, however, unique challenges for designers when compared to radio transmission systems. When communication system elements are in move, the...

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  • Multifrequency Wideband Sonar Array
    Publikacja
    • A. Eliminowicz
    • W. Lis
    • L. Zajączkowski

    - HYDROACOUSTICS - Rok 2012

    This paper describes of new approach to Multifrequency Wideband Arrays (MWA),applied piezocomposite technologies of the array elements. MWA operating in transmitting(Tx) and receiving (Rx) mode on two or three bands, requires state-of-the-art technology andefficient array designing than conventional array in which separate arrays for every band oreven separate Tx and Rx transducers/arrays are used. The new piezocomposite elements...

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  • Numerical investigations of the nonlinear waves generation in a bubble layer
    Publikacja

    Rozważano zagadnienie propagacji fal różnych częstotliwości wewnątrz warstwy z pęcherzykami. Przedstawiono model matematyczny zjawiska oraz wyniki badań teoretycznych. Badano zmiany widma fali bieżącej i odbitej jak również zmiany amplitud wybranych harmonicznych ciśnienia tych fal w funkcji grubości warstwy i koncentracji pęcherzyków.

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  • Signature of Hydrodynamic Pressure Field
    Publikacja

    W artykule przedstawiono wyniki obliczeń pola hydrodynamicznego ciśnienia wokół statku jako funkcję przestrzenną, obliczoną metodą brzegowego rozkładu osobliwości. Obliczone pole ciśnienia hydrodynamicznego jest porównywane z pomierzonym polem ciśnienia wokół okrętu na akwenie specjalnym, opis kształtu kadłuba jest przybliżony. Przedstawione wyniki obliczeń uzyskano stosując pojedynczą warstwę o ciągłym rozkładzie źródłowości....

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  • Signature of Hydrodynamic Pressure Field
    Publikacja

    W artykule przedstawiono wyniki obliczeń pola hydrodynamicznego ciśnienia wokół okrętu specjalnego jako funkcji przestrzennej, obliczonej metodą brzegową. Obliczone pola ćiśnienia hydrodynamicznego jest porównywane z pomierzonym polem okrętu na morzu, przy czym opis kształtu kadłuba okrętu jest przybliżony. Przedstawione wyniki obliczeń uzyskano stosując warstwę pojedynczą , którą stanowią źródła o rozkładzie ciągłym. Skonstruowany...

  • Using concentrated spectrogram for analysis of audio acoustic signals
    Publikacja

    The paper presents results of time-frequency analysis of audio acoustic signals using the method of Concentrated Spectrograph also known as ''Cross-spectral method'' or ''Reassignment method''. Presented algorithm involves signal's local group delay and channelized instantaneous frequency to relevantly redistribute all Short-time Fourier transform lines in time-frequency plain. The main intention of the paper is to compare various...

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  • Using Principal Component Analysis and Canonical Discriminant Analysis for multibeam seafloor characterisation data
    Publikacja

    The paper presents the seafloor characterisation based on multibeam sonar data. It relies on using the integrated model and description of three types of multibeam data obtained during seafloor sensing: 1) the grey-level sonar images (echograms) of seabed, 2) the 3D model of the seabed surface which consists of bathymetric data, 3) the set of time domain bottom echo envelopes received in the consecutive sonar beams. The classification...

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  • ''Voice Maps'' - system supporting navigation of the blind

    Referat wygłoszony na Konferencji SHA 2012,Gołuń, 22-25.V.2012.

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Rok 2011
  • A spice equivalent circuit for modeling the performance of dual frequency echo-sounder
    Publikacja

    The paper presents novel network equivalent circuit of piezoceramic circular disc transducers that takes into account thickness and radial mode of vibrations. The starting point of the analysis is 4-port description of circular disc element representing the solution of wave equation set in radial and thickness directions. The approximate solution for harmonic case is represented in the form of 4x4 matrix, which is synthesised and...

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  • Action-reaction based synthesis of acoustic wavefield equations
    Publikacja

    - HYDROACOUSTICS - Rok 2011

    The analysis of acoustic fields is usually based on the well-known mathematics of second order partial differential equations called wave equations. The author explores the duality and symmetry of linear fluid mechanics and develops two distinct equations of acoustics on the basis of a causal approach to local small-scale phenomena. Wavefields that are solutions of these equations have different composition, the spherical pressure...

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  • Application of OFDM technique to underwater acoustic data transmission
    Publikacja

    Performances of underwater acoustic communication (UAC) digital systems are strongly related to specific transmission properties of the underwater channel. Depending on the characteristics of the channel, an architecture and modulation techniques are usually implemented that are known as reliable solutions for data transmission in difficult radio channels. The OFDM technique seems to be the most promising nowadays. The parameters...

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  • Description of the hydrodynamic pressure field function around the ship hull
    Publikacja

    W artykule przedstawiono metodę aproksymacji pola hydrodynamicznego okrętu, wykorzystując pole obliczone metodą elementów skończonych. Punkty kontrolne umieszczono w środku paneli rozmieszczonych na kadłubie statku, na powierzchni dna morskiego oraz na powierzchni swobodnej; w p-ktach tych znajdują się osobliwości w postaci źródeł, upustów i/lub dipoli. Przedstawione wyniki obliczeń zostały uzyskane przy użyciu tych pierwszych...

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  • Doppler effect in the CW FM sonar

    When sonars are used for military purposes they have to ensure unobtrusive operation, a feature that can be potentially secured by 'silent sonar' or continuous wave frequency modulation sonars (CW FM sonars). The article presents how these sonars operate and identifies the relations between their parameters. The Doppler effect and its impact on the CW FM sonar are studied to identify how it affects the sonar's parameters. The results...

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  • Efficiency of acoustic heating in the Maxwell fluid
    Publikacja

    The nonlinear effects of sound in a fluid describing by the Maxwell model of the viscous stress tensor is the subject of investigation. Among other, viscoelastic biological media belong to this non-newtonian type of fluids. Generation of heating of the medium caused by nonlinear transfer of acoustic energy, is discussed in details. The governing equation of acoustic heating is derived by means of the special linear combination...

  • Efficiency of acoustic heating in the Maxwell fluid
    Publikacja

    The nonlinear effects of sound in a fluid describing by the Maxwell model of the viscous stress tensor is the subject of investigation. Among other, viscoelastic biological media belong to this non-newtonian type of fluids. Generation of heating of the medium caused by nonlinear transfer of acoustic energy, is discussed in details. The governing equation of acoustic heating is derived by means of the special linear combination...

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  • Numerical modeling of the nonlinear wave propagation in a bubble layer
    Publikacja

    Rozważano zagadnienie propagacji fali wewnątrz warstwy z pęcherzykami. Omówiono model matematyczny, przedstawiono przykładowe wyniki badań teoretycznych. Analizowano zmiany ciśnienia wewnątrz warstwy, falę odbitą i bieżącą w ośrodku otaczającym, badano gęstość widmową mocy. Badania teoretyczne przeprowadzono dla różnych grubości warstwy, koncentracji pęcherzyków i wartości parametrów fali padającej.

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  • Seafloor characterisation using multibeam data: sonar image properties, seabed surface properties and echo properties
    Publikacja

    In the paper, the approach to seafloor characterisation is presented. The multibeam sonars, besides their well verified and widely used applications like high resolution bathymetry and underwater object detection and imaging, are also the promising tool in seafloor characterization and classification, having several advantages over conventional single beam echosounders. The proposed approach relies on the combined, concurrent use...

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  • Silent Sonar with matched filtration

    Radars with continuous wave frequency (CW FM sonars) are used in radiolocation as 'silent sonars'. They determine the distance to target by measuring the difference between the frequency of the sounding signal and echo signal. The article presents the principle of operation and parameters of silent CW FM sonars. Target distance determined by these sonars is based on the signal at the output of the matched filter. The Doppler effect...

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  • Study of swimbladder morphometry of Baltic herring and sprat (development of measurement methodology)
    Publikacja

    - HYDROACOUSTICS - Rok 2011

    Effective management of Baltic clupeids, which are valuable commercially and ecologically,requires the biomass control. The acoustical techniques are recognized as effective in fishstock assessment. The study of Baltic herring and sprat individual backscatteringcharacteristics is required for the accurate biomass estimation using acoustical techniques.The previous measurements demonstrated significant...

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  • Transmission parameters of underwater communication channels
    Publikacja

    The underwater environment is tough and demanding as a communication channel for ultrasonic signals. The channel transmission characteristics in marine and inland waters depend much on local bathymetry and changing weather conditions. The architecture and performance of a reliable underwater acoustic communication (UAC) system should allow real-time adaptation of its transmission parameters to a large variety of possible channel...

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  • Unusual streaming in chemically reacting gases
    Publikacja

    Nonlinear stimulation of the vorticity mode caused by losses in the momentum of sound in the chemically reacting gas, is considered. The instantaneous dynamic equation which describes the nonlinear generation of the vorticity mode, is derived. It includes a quadratic nonlinear acoustic source. Both periodic and aperiodic sound may be considered as the origin of the vorticity flow. In the non-equilibrium regime of the chemical reaction,...

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  • Using phase of short-term Fourier transform for evaluation of spectrogram performance

    The concept of spectrogram performance evaluation which exploits information on phase of short-term Fourier transform (STFT) is presented. A spectrograph which is time-frequency analyzing tool, is compared to a filter bank that demultiplexes a signal. Local group delay (LGD) and channelized instantaneous frequency (CIF) is obtained for each filtered component signal. In presented solution the performance is evaluated using so-called...

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Rok 2010
  • 3D seafloor reconstruction using data from side scan and synthetic aperture sonar
    Publikacja

    Side scan and synthetic aperture sonars are widely used imaging systems in the underwater environment. They are relatively cheap and easy to deploy, in comparison with more powerful sensors, like multibeam echosounders. Although side scan and synthetic aperture sonars does not provide seafloor bathymetry directly, their records are finally related to seafloor images. Moreover, the analysis of such images performed by human eye...

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  • Broadband LFM signal source for a module-based diver detection sonar
    Publikacja

    - HYDROACOUSTICS - Rok 2010

    Praca przedstawia koncepcję źródła impulsów sondujących sonaru DDS, dla pogrupowanych po stronie nadawczej elementarnych sekcji przetwornika w moduły 8 lub 16 elementowe. Na podstawie oszacowania teoretycznego i pomiarów czwórnikowych określono potrzebną moc wyjściową i topologię tych nadajników. Przedstawione są też uzyskane na drodze pomiarów charakterystyki częstotliwościowe modułów przetwornika, razem z zastosowanym układem...

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  • Composition of data visualizations by sub-bottom profiler and multibeam echosounder in Matlab

    This paper contains description of procedure, which was elaborated in a numerical computing environment Matlab. The result of these procedures is a graphical composition of images obtained from two different hydroacoustic devices. It enables to compare different types of visualizations for the same geographical position and simultaneous work with graphical representation of all data types.

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  • Doppler estimation method for moving target location
    Publikacja

    Artykuł opisuje nowy algorytm lokalizacji obiektów ruchomych bazujących na analizie odchyłek dopplerowskich sygnałów odebranych z sieci hydrofonów rozmieszczonych równomiernie w obserwowanym akwenie. Źródłem analizowanych sygnałów są fale ciągłe o niskim natężeniu odbite od obiektu ruchomego. W artykule została przedstawiona postać algorytmu oraz wyniki symulacji komputerowych.

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  • Methods of data extraction from sub-bottom profiler's signal

    Data obtain during sounding Gdansk Bay with SES-2000 Standard parametric sub-bottom profiler has two types of information: envelope and pure signal. First is used to plot echograms in real time and contain envelope of echo. The second one is stored during sounding and can be processed after recording data. Comparison of results will be shown and discussed. First step in investigation was proper configuration of small measurement...

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  • Modernization of ASW Sonar SQS-56 at Gdańsk University of Technology

    Katedra Systemów Elektroniki Morskiej Politechniki Gdańskiej w latach 2008-2010 wykonała modernizację podkilowego sonaru do poszukiwania okrętów podwodnych SQS-56. Jest to sonar wyprodukowany w USA i zainstalowany na fregacie ORP Kościuszko. W ramach modernizacji zastosowano nowe szerokopasmowe impulsy sondujące z hiperboliczną modulacją częstotliwości generowanye w wielokanałowym nadajniku sterowanym mikroprocesorowo. Po stronie...

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  • On the acoustic backscattering by Baltic herring and sprat
    Publikacja

    - HYDROACOUSTICS - Rok 2010

    Accurate abundance estimate of Baltic clupeids, herring and sprat, is required for theirsustainable exploitation. The understanding the sound backscattering of individual fish isimportant for employing the acoustical techniques, which are widely used in the estimation.The previous studies demonstrated that the improvement of the understanding is critical forthe Baltic herring and sprat. It was the main...

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  • Pressure field in a plane layer
    Publikacja

    Praca prezentuje wyniki badań teoretycznych i numerycznych zagadnienia przejścia fal płaskich przez warstwę. Omówiono zagadnienie tworzenia i rozchodzenia się fal w poszczególnych warstwach. Zaproponowano model matematyczny opisujący zmiany ciśnienia wewnątrz warstwy. Analizowano ciśnienie wewnątrz warstwy, fale bieżące i odbite wewnątrz warstwy oraz w ośrodku otaczającym. Przedstawiono wyniki badań numerycznych.

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  • Seafloor characterisation using multibeam sonar echo signal processing and image analysis

    The authors propose the approach to multibeam seafloor characterisation which relies on the combined, concurrent use of two different techniques of multibeam sonar data processing. The first one is based on constructing the grey-level sonar images of seabed using the echoes received in the consecutive beams. Then, the parameters describing the local region of sonar image, namely, the local standard deviation of a grey level, and...

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  • The calculation long-term physical field created by water flow around the ship
    Publikacja

    The paper presents a description of the problems with fluid flow around a ship. Using the described solution of the problem were performed numerical calculations using the boundary element method. Were also presented preliminary results of the calculation of pressure fields at the bottom of the ship, taking into account the impact of the bottom.

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