Pawel S. Dabrowski

Dr. Pawel S. Dabrowski

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Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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31 October 2018 in Journal of Navigation
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Journal Article
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Cezary SpechtCezary Specht
Cezary Specht
JPJan Pawelski
Jan Pawelski
LSLeszek Smolarek
Leszek Smolarek
Mariusz SpechtMariusz Specht
Mariusz Specht
PDPawel S. Dabrowski
Pawel S. Dabrowski
Differential Global Positioning Systems (DGPS) and the European Geostationary Navigation Overlay Service (EGNOS) are included in a group of supporting systems (Ground-Based Augmentation System (GBAS)/Space-Based Augmentation System (SBAS)) for the American GPS. Their main task is to ensure better positioning characteristics (accuracy, reliability, continuity and availability) compared to GPS. Therefore, they are widely applied wherever GPS failures affect human safety, mainly in aviation, land and marine navigation. The aim of this paper is to assess the predictable positioning accuracy of DGPS and EGNOS receivers using a vessel manoeuvring in the Bay of Gdansk. Two receivers were used in the study: a Simrad MXB5 (DGPS) and a Trimble GA530 (EGNOS), which were simultaneously recording their coordinates. The obtained values were compared with the trajectory computed using a geodetic Global Navigation Satellite System (GNSS) receiver (Trimble R10) connected to a GNSS network, ensuring an accuracy of 2–3 cm (p = 0·95). During a four-hour measurement session, the accuracy statistics of these systems were determined based on around 11,500 positionings. Studies have shown that both positioning systems ensure a similar level of accuracy of their positioning services (approximately 0·5–2 m) and they meet the accuracy requirements set in published standards.

1 May 2019 in Advances In Space Research
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Journal Article
Closed access
Cezary SpechtCezary Specht
Cezary Specht
PDPawel S. Dabrowski
Pawel S. Dabrowski
JPJ. Pawelski
J. Pawelski
Mariusz SpechtMariusz Specht
Mariusz Specht
TST. Szot
T. Szot

18 April 2019 in PLOS ONE
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TSTomasz Szot
Tomasz Szot
Cezary SpechtCezary Specht
Cezary Specht
Mariusz SpechtMariusz Specht
Mariusz Specht
PDPawel S. Dabrowski
Pawel S. Dabrowski
Achieving single meter positioning accuracy by portable mobile devices still poses a major challenge to the satellite signal receivers constructors, despite gradual constellation completing process and the progress achieved in last decades. Nowadays popular smartphones are multifunctional devices that serve also as a personal navigation tool in navigation and sport activities using the global navigation satellite systems (GNSS) receivers installed. It would seem that introducing newer models to the global market would cause constant progress in the accuracies obtained, however, the study results do not confirm that. This study focused on Galaxy series smartphones of Samsung, one of the leading manufacturers worldwide, to examine its technological progress. The aim was to verify the thesis using statistical models and analyses to compare succeeding generations of smartphones on six devices from the series. The authors conducted two synchronous stationary measurement campaigns of 24 and 12 hours with one-second interval in obstacle-free environment which provided 70000+ and 30000+ statistical samples of position measurements. The reference values of true smartphones coordinates were determined by means of state-of-the-art precise surveying instruments and geodetic calculations. The results indicate that two newest generations of the Galaxy series included in the research, namely S6 and S7, obtained lower accuracies than their predecessors. Against the backdrop of lack of public availability of smartphones technical parameters, the conducted research results are relevant especially to smartphones positioning service users community.

18 July 2020 in Sensors
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Pawel BurdziakowskiPawel Burdziakowski
Pawel Burdziakowski
Cezary SpechtCezary Specht
Cezary Specht
PDPawel S. Dabrowski
Pawel S. Dabrowski
Mariusz SpechtMariusz Specht
Mariusz Specht
OLOktawia Lewicka
Oktawia Lewicka
AMArtur Makar
Artur Makar
The main factors influencing the shape of the beach, shoreline and seabed include undulation, wind and coastal currents. These phenomena cause continuous and multidimensional changes in the shape of the seabed and the Earth’s surface, and when they occur in an area of intense human activity, they should be constantly monitored. In 2018 and 2019, several measurement campaigns took place in the littoral zone in Sopot, related to the intensive uplift of the seabed and beach caused by the tombolo phenomenon. In this research, a unique combination of bathymetric data obtained from an unmanned surface vessel, photogrammetric data obtained from unmanned aerial vehicles and ground laser scanning were used, along with geodetic data from precision measurements with receivers of global satellite navigation systems. This paper comprehensively presents photogrammetric measurements made from unmanned aerial vehicles during these campaigns. It describes in detail the problems in reconstruction within the water areas, analyses the accuracy of various photogrammetric measurement techniques, proposes a statistical method of data filtration and presents the changes that occurred within the studies area. The work ends with an interpretation of the causes of changes in the land part of the littoral zone and a summary of the obtained results.

11 August 2020 in Remote Sensing
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Mariusz SpechtMariusz Specht
Mariusz Specht
Cezary SpechtCezary Specht
Cezary Specht
MSMaciej Szafran
Maciej Szafran
AMArtur Makar
Artur Makar
PDPawel S. Dabrowski
Pawel S. Dabrowski
PCPiotr Cywiński
Piotr Cywiński
Apart from extensive infrastructure protection, modern yacht ports should primarily provide vessels with navigational safety associated with their maneuvering on the approach fairway, as well as mooring in the port aquatory. For this reason, yachts entering the harbor should have up-to-date, accurate, and reliable charts of the port and its surroundings. This article presents hydrographic surveys conducted in the National Sailing Centre (NSC) yacht port at the Gdańsk University of Physical Education and Sport (GUPES), whose aim was to define and develop unique bathymetric and navigational charts of the harbor and the approach fairway. These can be used for example to manage berths in the marina or inform about the depths in the yacht port and on the approach fairway. The chart of the NSC-GUPES and its approach fairway is Poland’s first cartographic image of a harbor, performed entirely on the basis of surveys conducted by an Unmanned Surface Vehicle (USV). The study results demonstrated that the use of a small-sized USV in bathymetric measurements of yacht ports and marinas was significantly more effective than the traditional (manned) hydrographic surveys. Such vessels allow measurements to be carried out in hard-to-reach locations, even between mooring vessels, and in the immediate vicinity of quays. Thanks to the implemented automatic mode of steering on sounding profiles, USVs are equally efficient and capable of carrying out hydrographic surveys on a larger waterbody, i.e., the approach fairway.

Verified
Journal Article
Open access
PDF file
Cezary SpechtCezary Specht
Cezary Specht
OLOktawia Lewicka
Oktawia Lewicka
Mariusz SpechtMariusz Specht
Mariusz Specht
PDPawel S. Dabrowski
Pawel S. Dabrowski
Pawel BurdziakowskiPawel Burdziakowski
Pawel Burdziakowski
The human impact on the ecosystem has been particularly evident in the last century; it transforms the Earth’s surface on an unprecedented scale and brings about irreversible changes. One example is an oceanographic phenomenon known as a tombolo, i.e., a narrow belt connecting the mainland with an island lying near the shore formed as a result of sand and gravel being deposited by sea currents. The phenomenon contributes to an increase in the biogenic substance content in the littoral zone, which leads to increased cyanobacteria blooming in the summer period. Moreover, the debris accumulation in the littoral zone results in the mud formation, which makes the beach landscape less attractive. One of the main features of the tombolo phenomenon is its variability of shape, which includes the form of both the shore and the seabed adjacent to it. Therefore, to describe its size and spatio-temporal variability, it is necessary to apply methods for geodetic (the land) and hydrographic (the sea) measurements that can be carried out in different ways. The aim of the paper is to present the methodology for carrying out measurements of the tombolo oceanographic phenomenon using Unmanned Aerial Vehicles (UAV) and Unmanned Surface Vehicles (USV) on the example of a waterbody adjacent to the Sopot pier. It also presents the results of surveys carried out in November 2019 within this area. The study demonstrated that the integration of two measuring devices whose development began in the second decade of the 20th century, i.e., UAVs and USVs, enables accurate (even up to several centimeters) and reliable determination of the scale and variability of the phenomena occurring in the littoral zone.