Paweł Zalewski
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Paweł Zalewski has a total of 29 co-authors. Here are the top co-authors by number of shared publications:
- Jarosław Artyszuk
Faculty of Navigation, Maritime University of Szczecin, Wały Chrobrego St. 1-2, 70-500 Szczecin, Poland
3 shared publications - Adam Weintrit
Faculty of Navigation, Gdynia Maritime University, 3 Jana Pawła II Av., 81-345 Gdynia, Poland
2 shared publications - Mateusz Bilewski
Faculty of Navigation, Maritime University of Szczecin, 70-500 Szczecin, Poland
2 shared publications Adam Weintrit
Gdynia Maritime University
1 shared publication- Aleksandra Chełstowska
Faculty of Economics and Transport Engineering, Maritime University of Szczecin, 11 Pobożnego Str., 70-506 Szczecin, Poland
1 shared publication - Andrzej Bąk
Maritime University of Szczecin, Poland
1 shared publication
Latest Publications
- Open Access
- 19 September 2026
- Published by MDPI AG in Applied Sciences
- Vol. 16 (18) , 9294
Large Language Models in the Analysis of Radar Plotting Images in Accordance with COLREGs
The development of artificial intelligence (AI) opens new possibilities for the automatic interpretation of radar images in maritime navigation. Traditionally, the interpretation of radar indications requires the experience of the officer of the watch, who assesses the risk of collision and makes navigational decisions based on echo position, motion vectors, course, speed, Closest Point of Approach (CPA) and Time to Closest Point of Approach (TCPA). Systems using artificial intelligence can support this process through automatic object detection, tracking of their movement, classification of encounter situations, and indication of possible maneuvers in accordance with the Convention on the International Regulations for Preventing Collisions at Sea, 1972 (COLREGs). Maritime safety depends largely on the correct interpretation and application of the relevant COLREGs. The aim of this article is to present the capabilities, limitations and significance of generally available artificial intelligence tools like Large Language Models (LLMs) in the field of human–machine interaction. Attention is paid to the application of LLMs in radar plotting image analysis, the interpretation of navigational situations, and decision-making support from the perspective of marine traffic safety.
- 19 September 2026
- Published by MDPI AG in Applied Sciences
- Vol. 16 (18) , 9294
Open AccessLarge Language Models in the Analysis of Radar Plotting Images in Accordance with COLREGs
The development of artificial intelligence (AI) opens new possibilities for the automatic interpretation of radar images in maritime navigation. Traditionally, the interpretation of radar indications requires the experience of the officer of the watch, who assesses the risk of collision and makes navigational decisions based on echo position, motion vectors, course, speed, Closest Point of Approach (CPA) and Time to Closest Point of Approach (TCPA). Systems using artificial intelligence can support this process through automatic object detection, tracking of their movement, classification of encounter situations, and indication of possible maneuvers in accordance with the Convention on the International Regulations for Preventing Collisions at Sea, 1972 (COLREGs). Maritime safety depends largely on the correct interpretation and application of the relevant COLREGs. The aim of this article is to present the capabilities, limitations and significance of generally available artificial intelligence tools like Large Language Models (LLMs) in the field of human–machine interaction. Attention is paid to the application of LLMs in radar plotting image analysis, the interpretation of navigational situations, and decision-making support from the perspective of marine traffic safety.
- 1 June 2026
- Published by Silesian University of Technology in Transport Problems
- Vol. 21 (2) , 127-140
CONVENTIONAL AND UNCONVENTIONAL MANEUVERING OF CONTAINER VESSELS WITHOUT TUGBOAT ASSISTANCE AT SELECTED TERMINALS IN THE PORT OF ROTTERDAM
This paper describes the unberthing of container ships using conventional and unconventional maneuvers. The research has been carried out in the Maasvlakte in the Port of Rotterdam (Netherlands). This research analyzes the departure of ships with the onshore wind (various weather conditions) without tug assistance. The analysis of unberthing maneuvers, taking into consideration external conditions, draft, and load onboard, is based on the knowledge gained from the theory and experience in the performance of unconventional maneuvers without the assistance of a tugboat. Challenges posed to the maritime industry by developments in shipbuilding technology are discussed. This paper also presents the specifications of the ships under analysis and describes quays at the Port of Rotterdam that have been adapted for the berthing of container vessels. Unberthing maneuvers are also explained in detail. Additionally, the optimum unberthing method to be used in the Port of Rotterdam is presented. The results provide recommendations for captains of vessels of similar navigational and operational parameters.
- 1 June 2026
- Published by Silesian University of Technology in Transport Problems
- Vol. 21 (2) , 127-140
CONVENTIONAL AND UNCONVENTIONAL MANEUVERING OF CONTAINER VESSELS WITHOUT TUGBOAT ASSISTANCE AT SELECTED TERMINALS IN THE PORT OF ROTTERDAM
This paper describes the unberthing of container ships using conventional and unconventional maneuvers. The research has been carried out in the Maasvlakte in the Port of Rotterdam (Netherlands). This research analyzes the departure of ships with the onshore wind (various weather conditions) without tug assistance. The analysis of unberthing maneuvers, taking into consideration external conditions, draft, and load onboard, is based on the knowledge gained from the theory and experience in the performance of unconventional maneuvers without the assistance of a tugboat. Challenges posed to the maritime industry by developments in shipbuilding technology are discussed. This paper also presents the specifications of the ships under analysis and describes quays at the Port of Rotterdam that have been adapted for the berthing of container vessels. Unberthing maneuvers are also explained in detail. Additionally, the optimum unberthing method to be used in the Port of Rotterdam is presented. The results provide recommendations for captains of vessels of similar navigational and operational parameters.
- Open Access
- 29 January 2024
- Published by MDPI AG in Applied Sciences
- Vol. 14 (3) , 1131
The Use of a Double Bottom Trawl Set to Assess the Selectivity of Innovative Codends in Baltic Cod (Gadus morhua) Fishing
The overall objective of the study presented in this paper was to evaluate the selectivity properties of three innovative codends in Baltic cod fishing: (1) an ultracross codend of 120 mm square mesh, (2) an ultracross codend with additional devices reducing the speed of water flow—one tarpaulin diffuser and one net confusor of 120 mm mesh, and (3) an ultracross codend with two tarpaulin diffusers and two net confusors of 120 mm mesh. These codends were firstly tested at sea by single trawls and compared to T90 and herring codend trawls, allowing assessment of caught fish mass and dimensions. Additionally, a special divided small-mesh coat for the innovative codends enabled determination of the amount as well as the length and mass of cod escaping from the codend both while the trawling gear was towed and while it was hauled. Further validation of codend selectivity was carried out by a double (twin) bottom trawl set deployed from one cutter in various variants of innovative codends compared to standard ones. The results of the study indicate that the use of an innovative ultracross codend and innovative devices reducing the water flow speed (tarpaulin diffusers and 120 mm net confusors) significantly reduces the number of undersized cod (<35 cm), even down to 1.3%, in the haul and contributes to a reduction in invisible mortal discard.
- 29 January 2024
- Published by MDPI AG in Applied Sciences
- Vol. 14 (3) , 1131
Open AccessThe Use of a Double Bottom Trawl Set to Assess the Selectivity of Innovative Codends in Baltic Cod (Gadus morhua) Fishing
The overall objective of the study presented in this paper was to evaluate the selectivity properties of three innovative codends in Baltic cod fishing: (1) an ultracross codend of 120 mm square mesh, (2) an ultracross codend with additional devices reducing the speed of water flow—one tarpaulin diffuser and one net confusor of 120 mm mesh, and (3) an ultracross codend with two tarpaulin diffusers and two net confusors of 120 mm mesh. These codends were firstly tested at sea by single trawls and compared to T90 and herring codend trawls, allowing assessment of caught fish mass and dimensions. Additionally, a special divided small-mesh coat for the innovative codends enabled determination of the amount as well as the length and mass of cod escaping from the codend both while the trawling gear was towed and while it was hauled. Further validation of codend selectivity was carried out by a double (twin) bottom trawl set deployed from one cutter in various variants of innovative codends compared to standard ones. The results of the study indicate that the use of an innovative ultracross codend and innovative devices reducing the water flow speed (tarpaulin diffusers and 120 mm net confusors) significantly reduces the number of undersized cod (<35 cm), even down to 1.3%, in the haul and contributes to a reduction in invisible mortal discard.
- Open Access
- 1 January 2023
- Published by Faculty of Navigation in TransNav, the International Journal on Marine Navigation and Safety of Sea Transportation
- Vol. 17 (4) , 863-869
Challenges Related to Standardization of GNSS/RNSS Shipborne Equipment by International Maritime Organization (IMO)
In 2020 several member states initiated at IMO forum (NCSR subcommittee) a process to create a single set of generic performance standards consolidating all existing performance standards for shipborne satellite navigation system receiver equipment without creating any new requirements. After over 4 years the resultant generic framework for GNSS/RNSS subsystems has not been adopted yet and awaits further amendments. Analysis of the proposed standards with stress on harmonization issues of the existing, IMO recognized, global and regional navigation satellite systems and the expected impact of these generic standards of satellite navigation receivers on the maritime user are presented in this paper. Additionally the strengths, weaknesses, opportunities, and threats awaiting maritime or shipborne GNSS/RNSS equipment standardization process are outlined in the paper.
- 1 January 2023
- Published by Faculty of Navigation in TransNav, the International Journal on Marine Navigation and Safety of Sea Transportation
- Vol. 17 (4) , 863-869
Open AccessChallenges Related to Standardization of GNSS/RNSS Shipborne Equipment by International Maritime Organization (IMO)
In 2020 several member states initiated at IMO forum (NCSR subcommittee) a process to create a single set of generic performance standards consolidating all existing performance standards for shipborne satellite navigation system receiver equipment without creating any new requirements. After over 4 years the resultant generic framework for GNSS/RNSS subsystems has not been adopted yet and awaits further amendments. Analysis of the proposed standards with stress on harmonization issues of the existing, IMO recognized, global and regional navigation satellite systems and the expected impact of these generic standards of satellite navigation receivers on the maritime user are presented in this paper. Additionally the strengths, weaknesses, opportunities, and threats awaiting maritime or shipborne GNSS/RNSS equipment standardization process are outlined in the paper.
- Open Access
Power Consumption and Effectiveness of Azimuth Stern-Drive (ASD) Tug While Assisting at Ship’s Bow
The purpose of this article is to present a methodical approach to increasing the efficiency of a tug with an azimuth stern drive (ASD). The difficulties in the bow-to-bow (as a reverse tractor) operations of an azimuth stern-drive tug, while pulling at the assisted (towed) ship’s bow, are investigated through a parametric study. The authors’ original generic analytical model of a tug in a steady state is utilised. Various design and operation options are also compared, which cover the escort speed, hawser angle, and relative location of the towing point, among others. The latter also means a shift to stern-to-bow operation. The thruster power required and the remaining surplus for executing new alignment (steering) orders are assessed. The study is, thus, aimed at energy savings for the whole operation and, consequently, at long-term harbour-tug-fleet energy effectiveness. The basic output of the present research is the comparison of the behavioural and control patterns of various tug arrangements at a ship’s bow. The results of the study show a slight advantage for a midship winch tug working through her stern for bow operation (stern-to-bow) over the reverse tractor acting bow-to-bow. Comparing various tug designs or operation options is difficult due to complicated tug dynamics and statics patterns under the hawser action. Both relative and absolute towing forces have to be considered (a high relative force may result in a low absolute force, much less than ordered by the pilot), with some geometrical and safety constraints additionally. The practical implementation of the conducted research should cover the guidance and training rendered to tug masters in the scope of the operational limitations of a particular tug and towards the design or acquisition of the tug that is best-suited for a particular harbour operation.
Open AccessPower Consumption and Effectiveness of Azimuth Stern-Drive (ASD) Tug While Assisting at Ship’s Bow
The purpose of this article is to present a methodical approach to increasing the efficiency of a tug with an azimuth stern drive (ASD). The difficulties in the bow-to-bow (as a reverse tractor) operations of an azimuth stern-drive tug, while pulling at the assisted (towed) ship’s bow, are investigated through a parametric study. The authors’ original generic analytical model of a tug in a steady state is utilised. Various design and operation options are also compared, which cover the escort speed, hawser angle, and relative location of the towing point, among others. The latter also means a shift to stern-to-bow operation. The thruster power required and the remaining surplus for executing new alignment (steering) orders are assessed. The study is, thus, aimed at energy savings for the whole operation and, consequently, at long-term harbour-tug-fleet energy effectiveness. The basic output of the present research is the comparison of the behavioural and control patterns of various tug arrangements at a ship’s bow. The results of the study show a slight advantage for a midship winch tug working through her stern for bow operation (stern-to-bow) over the reverse tractor acting bow-to-bow. Comparing various tug designs or operation options is difficult due to complicated tug dynamics and statics patterns under the hawser action. Both relative and absolute towing forces have to be considered (a high relative force may result in a low absolute force, much less than ordered by the pilot), with some geometrical and safety constraints additionally. The practical implementation of the conducted research should cover the guidance and training rendered to tug masters in the scope of the operational limitations of a particular tug and towards the design or acquisition of the tug that is best-suited for a particular harbour operation.
- Open Access
- 22 October 2022
- Published by MDPI AG in Remote Sensing
- Vol. 14 (21) , 5291
Evolution of Maritime GNSS and RNSS Performance Standards
The primary means for electronic position fixing in use in contemporary maritime transport are shipborne GPS (Global Positioning System) receivers or DGPS (Differential GPS) receivers. More advanced GNSS (Global Navigation Satellite System) or RNSS (Regional Navigation Satellite Systems) receivers are able to process combined signals from American GPS, Russian GLONASS, Chinese Beidou (BDS), European Galileo, Indian IRNSS, and Japan QZSS. Satellite-based augmentation systems (SBAS) are still not commonly used in the maritime domain, especially onboard vessels certified under international SOLAS convention. The issues and weaknesses of existing International Maritime Organization recommendations, guidelines, requirements, performance standards, and policies on GNSS shipborne sensors are discussed and presented in the paper. Many problems that have already been dealt with in other means of transportation are still to be solved in the maritime domain. The integrity monitoring is addressed as the main issue, and recommendations based on solutions implemented in aviation and the latest research are proposed. Finally, the strengths, weaknesses, opportunities, and threats awaiting maritime GNSS standardization process are outlined.
- 22 October 2022
- Published by MDPI AG in Remote Sensing
- Vol. 14 (21) , 5291
Open AccessEvolution of Maritime GNSS and RNSS Performance Standards
The primary means for electronic position fixing in use in contemporary maritime transport are shipborne GPS (Global Positioning System) receivers or DGPS (Differential GPS) receivers. More advanced GNSS (Global Navigation Satellite System) or RNSS (Regional Navigation Satellite Systems) receivers are able to process combined signals from American GPS, Russian GLONASS, Chinese Beidou (BDS), European Galileo, Indian IRNSS, and Japan QZSS. Satellite-based augmentation systems (SBAS) are still not commonly used in the maritime domain, especially onboard vessels certified under international SOLAS convention. The issues and weaknesses of existing International Maritime Organization recommendations, guidelines, requirements, performance standards, and policies on GNSS shipborne sensors are discussed and presented in the paper. Many problems that have already been dealt with in other means of transportation are still to be solved in the maritime domain. The integrity monitoring is addressed as the main issue, and recommendations based on solutions implemented in aviation and the latest research are proposed. Finally, the strengths, weaknesses, opportunities, and threats awaiting maritime GNSS standardization process are outlined.
- Open Access
- 8 July 2022
- Published by MDPI AG in Applied Sciences
- Vol. 12 (14) , 6914
Complex Monitoring of Vertical Land Motions Corresponding to Geological Structure of Coastal and River Areas in Northwestern Poland
This paper presents a study of vertical land movements conducted in northwestern Poland, covering the city of Szczecin. The land of Szczecin is made up of organic soils, covered in many places by water (lagoons, rivers, and lakes), which are susceptible to displacement; therefore, benchmarks in this area are susceptible to changes in height. The analysis of the geological structure of the near-surface layer of the Szczecin area, such as organic soils, sands, and clays, was carried out. The detailed recognition of geological structure in connection with height changes of benchmarks made it possible to locate stable benchmarks in the researched area. In the first step, the authors chose benchmarks in a stable geological structure based on archive data from the Polish Geodesy Documentation Center. In the second step, precise GNSS 3D measurements were performed in the direct vicinity of these benchmarks in order to verify their stability. Verified stations provided a reference for the reliable monitoring of the deformation of other surfaces resulting, for example, from changes in organic sediments. Existing and new engineering structures erected in the area of the Oder River Szczecin islands were selected for the final research of vertical land motions. Static GNSS observations were conducted in November 2020 and May 2021.
- 8 July 2022
- Published by MDPI AG in Applied Sciences
- Vol. 12 (14) , 6914
Open AccessComplex Monitoring of Vertical Land Motions Corresponding to Geological Structure of Coastal and River Areas in Northwestern Poland
This paper presents a study of vertical land movements conducted in northwestern Poland, covering the city of Szczecin. The land of Szczecin is made up of organic soils, covered in many places by water (lagoons, rivers, and lakes), which are susceptible to displacement; therefore, benchmarks in this area are susceptible to changes in height. The analysis of the geological structure of the near-surface layer of the Szczecin area, such as organic soils, sands, and clays, was carried out. The detailed recognition of geological structure in connection with height changes of benchmarks made it possible to locate stable benchmarks in the researched area. In the first step, the authors chose benchmarks in a stable geological structure based on archive data from the Polish Geodesy Documentation Center. In the second step, precise GNSS 3D measurements were performed in the direct vicinity of these benchmarks in order to verify their stability. Verified stations provided a reference for the reliable monitoring of the deformation of other surfaces resulting, for example, from changes in organic sediments. Existing and new engineering structures erected in the area of the Oder River Szczecin islands were selected for the final research of vertical land motions. Static GNSS observations were conducted in November 2020 and May 2021.
- Open Access
Energy Savings by Optimization of Thrusters Allocation during Complex Ship Manoeuvres
The International Maritime Organization adopted a strategy to reduce the total annual GHG emissions from international shipping by at least 50% by 2050, compared to 2008 levels. The European Union proposed an even farther reaching transformation: the European Commission adopted a set of proposals to make the EU’s transport policies fit for reducing net greenhouse gas emissions by at least 55% by 2030, compared to 1990 levels. Therefore, all industrial actions in line and consistent with these strategies are essential. One of such activities may be a gradual transition from the most common independent controls of transport ships’ thrusters, propellers, and rudders to an integrated, power optimized, 3 degrees of freedom joystick control. In this paper, the full mission bridge simulator (FMBS) research on potential energy savings and, consequently, a GHG emission reduction, while steering a RoPax twin-screw ferry equipped with bow thrusters by a joystick control, is presented. The task of navigators engaged in the research was to steer the vessel either via classic engine, rudder, and thruster levers or via a joystick while (1) following the predefined straight track, (2) rotating at the turning area, and (3), finally, crabbing (moving sideways) until stopping at the quay fenders. The conclusions are that energy savings of approximately 10% can be expected for berthing manoeuvres controlled by a joystick, compared to independent actuators’ controls. These conclusions have been drawn from a statistical analysis of the ship’s energy consumption during typical manoeuvring phases of 18 berthing operations performed in FMBS.
Open AccessEnergy Savings by Optimization of Thrusters Allocation during Complex Ship Manoeuvres
The International Maritime Organization adopted a strategy to reduce the total annual GHG emissions from international shipping by at least 50% by 2050, compared to 2008 levels. The European Union proposed an even farther reaching transformation: the European Commission adopted a set of proposals to make the EU’s transport policies fit for reducing net greenhouse gas emissions by at least 55% by 2030, compared to 1990 levels. Therefore, all industrial actions in line and consistent with these strategies are essential. One of such activities may be a gradual transition from the most common independent controls of transport ships’ thrusters, propellers, and rudders to an integrated, power optimized, 3 degrees of freedom joystick control. In this paper, the full mission bridge simulator (FMBS) research on potential energy savings and, consequently, a GHG emission reduction, while steering a RoPax twin-screw ferry equipped with bow thrusters by a joystick control, is presented. The task of navigators engaged in the research was to steer the vessel either via classic engine, rudder, and thruster levers or via a joystick while (1) following the predefined straight track, (2) rotating at the turning area, and (3), finally, crabbing (moving sideways) until stopping at the quay fenders. The conclusions are that energy savings of approximately 10% can be expected for berthing manoeuvres controlled by a joystick, compared to independent actuators’ controls. These conclusions have been drawn from a statistical analysis of the ship’s energy consumption during typical manoeuvring phases of 18 berthing operations performed in FMBS.
- Open Access
- 14 May 2021
- Published by MDPI AG in Applied Sciences
- Vol. 11 (10) , 4456
Determination of the Waterway Parameters as a Component of Safety Management System
This article presents the use of a computer application codenamed “NEPTUN” to ascertain the waterway parameters of the modernised Świnoujście–Szczecin waterway. The designed program calculates the individual risks in selected sections of the fairway depending on the input data, including the parameters of the ship, available water area, and positioning methods. The collected data used for analyses in individual modules are stored in a SQL server of shared access. Vector electronic navigation charts of S-57 standard specification are used as the cartographic background. The width of the waterway is calculated by means of the method developed on the basis of the modified PIANC guidelines. The main goal of the research is to prove and demonstrate that the designed software would directly increase the navigation safety level of the Świnoujście–Szczecin fairway and indicate the optimal positioning methods in various navigation circumstances.
- 14 May 2021
- Published by MDPI AG in Applied Sciences
- Vol. 11 (10) , 4456
Open AccessDetermination of the Waterway Parameters as a Component of Safety Management System
This article presents the use of a computer application codenamed “NEPTUN” to ascertain the waterway parameters of the modernised Świnoujście–Szczecin waterway. The designed program calculates the individual risks in selected sections of the fairway depending on the input data, including the parameters of the ship, available water area, and positioning methods. The collected data used for analyses in individual modules are stored in a SQL server of shared access. Vector electronic navigation charts of S-57 standard specification are used as the cartographic background. The width of the waterway is calculated by means of the method developed on the basis of the modified PIANC guidelines. The main goal of the research is to prove and demonstrate that the designed software would directly increase the navigation safety level of the Świnoujście–Szczecin fairway and indicate the optimal positioning methods in various navigation circumstances.
- 13 October 2020
- Published by Springer Nature
- p. 402-414
A Critical Analysis of the IMO Description of Maritime Services in the Context of e-Navigation
- 13 October 2020
- Published by Springer Nature
- p. 402-414
A Critical Analysis of the IMO Description of Maritime Services in the Context of e-Navigation