Zbigniew Łubniewski - Publications - Bridge of Knowledge

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Year 2024
  • The Application of a Mobile Unmanned Device for Monitoring Water and Sediment Pollution in the Port of Gdynia
    Publication

    - Water - Year 2024

    Pollution in the Port of Gdynia can encompass various types of substances and contaminants that affect the quality of water and sediment in this region. Ships entering and leaving the port can release pollutants such as oil, fuel, waste, and chemicals into the water. Controlling and monitoring these pollutants is a crucial part of environmental stewardship. In recent years, uncrewed units have been increasingly in use for in situ...

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Year 2023
Year 2022
Year 2021
  • DOP and Pseudorange Error Estimation in Mobile GNSS Systems for Android OS Applications
    Publication

    In the near past, GNSS (Global Navigation Satellite Systems) were only offered for a narrow group of recipients. Nowadays, thanks to mobile devices, they are available to anyone and everywhere. Personal navigation, searching for POI (Point of Interest), etc., had become a basic essential activity. Thanks to the widespread and availability of smartphones each user can obtain information considering his or her location even in an...

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  • DOP and Pseudorange Error Estimation in Urban Environments for Mobile Android GNSS Applications
    Publication

    Just a couple of years ago, GNSS (Global Navigation Satellite Systems) were available only for a narrow group of users. Currently, with the outbreak of mobile devices, they are accessible to anyone and everywhere. Urban navigation or searching for POIs (Points of Interest) had become an everyday activity. With the availability of consumer electronics and wireless technologies, each user can obtain information considering his or...

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  • Measurement of Seafloor Acoustic Backscatter Angular Dependence at 150 kHz Using a Multibeam Echosounder
    Publication
    • K. Trzcińska
    • J. Tęgowski
    • P. Poćwiardowski
    • Ł. Janowski
    • J. Zdroik
    • A. Kruss
    • M. Rucińska
    • Z. Łubniewski
    • J. S. von Deimling

    - Remote Sensing - Year 2021

    Acoustic seafloor measurements with multibeam echosounders (MBESs) are currently often used for submarine habitat mapping, but the MBESs are usually not acoustically calibrated for backscattering strength (BBS) and cannot be used to infer absolute seafloor angular dependence. We present a study outlining the calibration and showing absolute backscattering strength values measured at a frequency of 150 kHz at around 10–20 m water...

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Year 2020
Year 2019
Year 2018
Year 2017
  • Multibeam data processing for 3D object shape reconstruction
    Publication

    The technology of hydroacoustic scanning offers an efficient and widely-used source of geospatial information regarding underwater environments, providing measurement data which usually have the structure of irregular groups of points known as point clouds. Since this data model has known disadvantages, a different form of representation based on representing surfaces with simple geometric structures, such as edges and facets,...

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  • Multibeam Sonar Data Processing for Seafloor Classification
    Publication

    Despite many years of the development of methodology for sensing the seafloor by means of underwater acoustics, the currently used techniques are still not mature enough and not ready to be utilised in numerous different (i.e. with respect to a water region character, used equipment type etc.) tasks. Therefore the hydroacoustic methods, both utilising vertical observations (e.g. by singlebeam echosounders), as well as those relying...

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  • On Algorithm Details in Multibeam Seafloor Classification
    Publication

    Remote sensing of the seafloor constitutes an important topic in exploration, management, protection and other investigations of the marine environment. In the paper, a combined approach to seafloor characterisation is presented. It relies on calculation of several descriptors related to seabed type using three different types of multibeam sonar data obtained during seafloor sensing, viz.: 1) the grey-level sonar images (echograms)...

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  • Optimized AVHRR land surface temperature downscaling method for local scale observations: case study for the coastal area of the Gulf of Gdańsk
    Publication

    Satellite imaging systems have known limitations regarding their spatial and temporal resolution. The approaches based on subpixel mapping of the Earth’s environment, which rely on combining the data retrieved from sensors of higher temporal and lower spatial resolution with the data characterized by lower temporal but higher spatial resolution, are of considerable interest. The paper presents the downscaling process of the land...

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Year 2016
Year 2015
Year 2014
Year 2013
Year 2012
Year 2011
Year 2010
Year 2009
Year 2008
Year 2007
  • Seafloor relief reconstruction from side scan sonar data
    Publication

    Side scan sonar is one of the most widely used imaging systems in the underwater environment. It is relatively cheap and easy to deploy, in comparison with more powerful sensors. Although side scan sonar does not provide seafloor bathymetry directly, its records are directly related to seafloor images. In the paper, the method for 3D seafloor relief reconstruction from side scan sonar data is presented. The method is based on the...

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Year 2006
Year 2005
Year 2004
  • A novel approach to bottom scattering using a narrow acoustic beam.
    Publication

    - Year 2004

    Przedstawiono model opisujący w prosty sposób rozpraszanie sygnału akustycznego na dnie morskim jako filtr liniowy z odpowiedzią impulsową o zmieniającej się w czasie chwilowej dominującej częstotliwości. Przedyskutowano pasujący do tego modelu przypadek zbioru punktowych rozpraszaczy równomiernie rozmieszczonych na powierzchni dna, w tym wpływ takich parametrów jak głębokość oraz odległość pomiędzy rozpraszaczami.

  • Seafloor backscattering: numerical simulation vs. filter theory approach.
    Publication

    - Year 2004

    Przedstawiono model opisujący rozpraszanie sygnału akustycznego na nierównomiernej, regularnie sfalowanej powierzchni dna morskiego jako filtr liniowy z odpowiedzią impulsową o zmieniającej się w czasie chwilowej dominującej częstotliwości. Porównano przewidywania modelu z wynikami otrzymanymi w wyniku złożonych obliczeniowo symulacji numerycznych opartych na fizycznym modelu zjawiska wykorzystującym aproksymację Kirchhoffa. Wstępnie...

  • Sensitivity of echo parameters to seafloor properties and depth variability.
    Publication

    - Year 2004

    Przeprowadzono badanie użyteczności wybranych parametrów echa akustycznego, w szczególności wymiaru fraktalnego oraz momentów spektralnych obwiedni, w klasyfikacji dna morskiego, ze szczególnym uwzględnieniem wpływu zmieniającej się głębokości. Wykorzystano numeryczną symulację rozpraszania echa na dnie oraz innych elementów procesu akustycznego sondowania dna, w tym także procedurę kompensacji wpływu zmian głębokości dna na echo.

Year 2003
Year 2002

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