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  • Złoczowska, Ewelina; Ślączka, Wojciech (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This study characterizes the distribution chain of liquefied natural gas (LNG) in Poland, using the terminal in Świnoujście as the “source of LNG”. The focus is primarily on the possibility of LNG distribution for road transport, taking into account the effective use of its energy potential. During the transport and storage of LNG it was found that the evaporation of LNG, the so-called boil-off gas (BOG), is a significant problem that leads to an increased pressure in the tank. Therefore, the possibility of using BOG in individual links of the LNG supply chain is indicated. One prospect is its compression to high pressure, which produces compressed natural gas (CNG) fuels. Thus, this paper specifies the influence of the initial BOG gas pressure on the unit compression work and analyses the change in the compression unit work, which depends on the final CNG fuel pressure, with a specific assumption for the BOG pressure.
  • Dembińska, Izabela (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Dear Readers, We are living faster and more intense these days. This dictatorship of time is also visible in the world of science. The lifetime of research results shortens progressively. Research problems are quickly becoming out of date. It is not a destructive factor for researchers but a challenge they need to face. The only thing to comprehend here is that research needs to be carried out quickly and flexibly. Obviously, it is not an easy task as new trends and, consequently, new research problems appear more often as well. We are glad to present to you a new issue of our journal, the Scientific Journals of the Maritime University of Szczecin. This issue presents views, opinions and research results grounded in various research fields. We grouped the submitted papers into the following themed sections: Civil Engineering and Transport, Material and Mechanical Engineering, Information and Communication Technology, Sustainability Management. The Civil Engineering and Transport section holds five articles. In the first one, the authors present trends in building offshore wind turbines and characterise ships used for installation and maintenance of wind turbines. The analysis is based on the assumption that safety of sailing on port waterways is the basic limitation in building ports and terminals for handling ships used to build OWT and expanding their size. The goal is to present a method of measuring port waterways for ships used for transporting and building offshore wind turbines. The author of the second article claims that recent years brought about more intense works on autonomous means of transportation, including sea ships. This review presents key features of the construction and exploitation of autonomous ships. The analysis presented in the third article of this section views hydrofoils as instruments to improve the hydrodynamic aspects of maritime equipment. The authors simulated the movements of a 2D NACA0012 hydrofoil moving in the water close to its free surface, with the optimiser based on the coupling with the net’s morphing used to maximise the lift-to-pull ratio. It was observed that the shape of the optimised hydrofoil depends on the angle of attack, which triggered various lift-to-resistance coefficients. This served as a basis for a general conclusion that the optimal angle of attack for installing a hydrofoil on the ship’s hull is 5°. The next paper was inspired by the 400 m container ship called Ever Given was grounded on the Suez Canal, blocking the busiest shipping lane – handling 12% of global sea trade – for 6 days. That event enforced finding an alternative waterway for the Suez Canal, with a smaller risk of being blocked and without the necessity of going around the entire African continent. Such routes joining the Pacific and the Atlantic are found in the Arctic and the global warming make them increasingly accessible. However, assessing their longevity requires a multifaceted analysis based on available professional navigation publications, academic works and knowledge regarding polar sailing conditions. The paper discusses three alternative lanes: the Northern Sea Route in the eastern part of the Arctic Ocean along the coast of the 6 Scientific Journals of the Maritime University of Szczecin 70 (142) Russian Federation, the Northwest Passage through the western part of the Arctic, avoiding waters belonging Greenland, Canada and the USA, and a route near the North Pole, known as the Transpolar Sea Route. The analysis of those lanes clearly points to the Northern Sea Route as the only option currently viable. The last paper in this section discusses the changeability of time series in Forward Freight Agreements on the market of dry bulk cargo. Firstly, it determines the changeability and characteristics of unique time series for prices in FFA. Next, it applies the ARIMA-GJRGARCH model for time-based charter within Capesize FFA and particular one-month charter contracts for cruises, which creates long or short signals that help market users in FFA-based trade or hedging. The aim of the research is to determine whether this method focused on changeability is efficient in modelling FFA time series and whether it helps the market players in more precise estimates regarding unstable days. The Material and Mechanical Engineering section features one article. It proves that the assessment of propulsion system failure in a ship triggers excessive costs and a decrease in the company’s prestige in the maritime business. The employees of land/ship crew have to detect and minimise failures in ship propulsion systems in advance to ensure the continuity of ship operation. The paper uses registered data on the failures in four different ships. The failures were examined thoroughly as the ships have similar propulsion systems. The investigation into the propulsion system and its subsystems shows that the ship’s main engine is the most reliable. Furthermore, the most crucial elements were the main engine’s cylinders as subsystems. The research is a valuable source of information not only for scientists, but also for experts and companies working on the reliability, accessibility and maintenance of ships. The Information and Communication Technology section features one paper. It notices that as a result of the accessibility of mobile devices and common broadband access worldwide, the number of Internet users is constantly growing and their awareness when it comes to the absorbed content is increasing with it. Many service providers and operators focus on monitoring Quality of Network and Quality of Service parameters, especially those affected by throughput and delays. However, for most end users, quality is viewed as subjective Quality of Experience which is a mixture of several individual factors. The article presents QoN assessment carried out under working conditions in real time on the university campus, with particular focus on general efficiency of the mobile networks. The Sustainability Management section presents a paper stating that the determination of dynamic areas of searching for wreckage and/or movement of pollutions through the waters of the Szczecin Lagoon requires most of all the knowledge and identification of hydrometeorological conditions in that area. For this reason, the authors compared wind parameters from various sources at the meteorological stations located near the Szczecin Lagoon. Wind speed and direction were obtained from Ueckermuende, I Brama Torowa (Szczecin Maritime Office) and Kopice (anemometer of the Maritime University in Szczecinie). Analysing data on wind direction was based on methods and tools of directional statistics. I hope that the papers included in this issue will trigger broad interest and stimulate further reflections, discussions and research.
  • Rutkowska, Gabriela; Żółtowski, Mariusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Concrete is currently the most widely used man-made composite material and second only to water in the entire range of materials used. It is a material with a high potential to adapt to specific operating conditions and can be made from local raw materials (aggregate, cement, water, and mineral additives), which can be selected to minimize the carbon footprint. The use of fly ash from the thermal conversion of sewage sludge in concrete is in accord with the advice on waste management proposed in the European Union. This paper presents the results of research on the effect of the partial replacement of Portland cement with this material on the strength parameters, frost resistance, and carbonation of concrete compared to reference concrete and to concrete containing a conventional additive – siliceous fly ash. In addition, the potential environmental impact of the use of sewage sludge ash was investigated by determining the leachability of heavy metals. Concrete mixtures of C20/25 ordinary concrete, based on CEM I 42.5R Portland cement, with varying ash contents comprising 0–20% of the cement mass, were produced for the experimental work. The obtained test results confirmed the possibility of producing plain concrete modified with fly ash from the thermal treatment of sewage sludge and the concrete’s compliance with the environmental requirements relating to the leaching of heavy metals.
  • Vilke, Siniša; Tadić, Frane; Ćelić, Jasmin; Debelić, Borna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper seeks to highlight the impact of the increasing container throughput in northern Adriatic ports on air quality. A comparative analysis of air quality is given, which consist of certain environmental parameters at selected measuring stations near the container terminals of the northern Adriatic ports Rijeka, Trieste, Koper, and Venice. The parameters were analyzed based on a limited amount of air quality monitoring data for the port areas. As the port transport sector increases pollutant emissions, the results of these analyzes can also be used to take appropriate measures to reduce these particulate matter emissions. The aim of this paper is to determine the impact of increasing the container throughput within the ports of the northern Adriatic Sea on air quality, based on certain environmental parameters related to the shipping or delivery of containers by road. The results of the research, based on available data, have shown that the increase in container throughput of the northern Adriatic ports has not decreased the air quality of urban areas of the respective port cities. The air quality value of the northern Adriatic ports is substantially below the limits set by the EU Air Quality Directive (2008/50), thus it does not affect the health of the inhabitants of the analyzed cities.
  • Buse, Hauke; Spangemacher, Lars; Fröhlich, Siegmund (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The current article describes the basics and prospects of the ultrasound-assisted cleaning of shell and tube heat exchangers that are used, e.g., on ships. A main issue of seawater heat exchangers is their clogging. After a certain operating time, the fouling process (barnacles, algae, etc.) starts, which results in a decreased performance that produces a noticeably reduced flow rate and a declining transmission of heat energy. Based on the current state of the art, heat exchangers are cleaned by mechanical or chemical (CIP, cleaning in place) methods. Especially on ship-based systems, a mechanical cleaning in very narrow spaces can be difficult and the usage of chemicals for CIP may generally be prohibited. An ultrasound-assisted cleaning would significantly save time and manning. Based on previous experiments, a test reactor represented by a shell and tube heat exchanger with ultrasound-assisted cleaning has been designed. A FEM (finite element method) simulation is performed to provide information about the ultrasound power distribution inside the reactor. Further, the assembly and commissioning of the test reactor with associated comparative measurements were carried out, which are also reported here.
  • Gucma, Michalina; Deja, Agnieszka (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper discusses the use of satellite tracking during an environmental disaster at sea, and it assesses the possibility of using remote sensing imagery captured by satellites using multispectral cameras and synthetic-aperture radar (SAR). This study is based on scientific literature and satellite tracking of the X-Press Pearl container ship disaster, which involved the EO-Browser platform. The purpose of this paper is to assess selected remote sensing methods for detecting and tracking marine pollution. The first part of the paper discusses satellite tracking of the X-Press Pearl disaster. The second part focuses on evaluation of the quality of remote sensing imagery from satellites and aircraft, when taking weather conditions into consideration. It should be noted that the research was conducted in real time when the incident occurred. News about the accident was also tracked in real time, allowing for a thorough analysis of the incident and, thus, an assessment of the different sensing systems. Although research on such disasters is crucial for the protection of the marine environment, scientific literature on this topic remains limited. This research area is very important for the protection of the marine environment, in the context of looking for solutions to these issues.
  • Czapliński, Wojciech; Gąsowski, Wojciech (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The Automatic Identification System (AIS) device is mandatory for ships that comply with the International Convention for the Safety of Life at Sea (SOLAS). AIS is intended for vessel traffic monitoring to improve shipping safety. In the examined area, the base station received 22 128 345 messages in April 2019. Approximately 80% of these messages included position reports, which were subjected to geospatial analysis. One possible utilization of AIS messages is used in an intelligent maritime transport statistics production system called TranStat in the Gospostrateg project. This specific study compares the speed of executing geospatial queries in a relational PostgreSQL database engine and a non-relational MongoDB database engine. For the purpose of this research, we have defined four AIS datasets, four test polygons of varied number of vertices, and a reference point on a fairway. The tests were used to assess the execution of the queries in a database that returns the number of ships located in a predefined area and the number of ships located at a preset distance from the defined point. It has been determined from the test results that test queries are performed faster and data stored in the database occupy less disk space in MongoDB than in PostgreSQL. Faster geospatial analysis of AIS messages may improve the navigation safety by earlier detection of dangerous situations.
  • Wiaterek, Daniel; Chybowski, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The purpose of this paper is to present the results of a query aimed at assessing the validity of the topic of crankcase explosions prevention in the main marine engines. The study takes into account the engine type, engine manufacturer, ship’s age, accident severity, ship’s location at the time of the incident, and the share of fatal accidents in the analyzed population of crankcase explosions. One of the primary hazards associated with offshore and deep-sea ship operations – and primarily ship power plants – are fires and explosions that result in accidents and incidents with an average frequency of 60 days. This paper discusses the actuality of crankcase explosion hazards in the main propulsion engines of various types of sea vessels. The assessment was made based on the results of a statistical analysis of historical data from 1972 to 2018. The methodology consisted of three stages: (1) a selection query to obtain the source data, (2) analysis of the obtained results (data separation, extraction of additional information, and statistical analysis), (3) synthesis of the obtained information, and drawing conclusions about the numerical indicators describing the statistical distribution of individual events for the given evaluation criteria. The analysis showed that the risk of crankcase explosions affects ships of all ages – both in crosshead (31%) and trunk piston engines (61%) – and that the number of serious incidents (67%) remained constant over the investigated period. Half of all incidents occurred on vessels younger than 15 years old. 58% of explosions took place in engines of the most popular prime movers manufacturers. The probability that a main engine crankcase explosion will result in injury or death is 17.34%.
  • Ganjgani, Arman Aghaei; Ghassemi, Hassan; Ghiasi, Mahmoud (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper investigates the effect of buoys and a clump weight on the mooring lines and the dynamic response of the floating platform. The full-scale of the OC4-DeepCwind semisubmersible FOWT platform is analyzed using the boundary element method (BEM) with ANSYS-AQWA software, when considering regular wave conditions. Platform motions and mooring line tension in the surge, heave, and pitch are presented and discussed in the time domain analyses (TDA) and frequency domain analyses (FDA). Validation is performed by compression of the platform motion RAO and the fairlead tension RAO magnitudes in the surge, heave, and pitch (for both numerical and experimental data) under seven sea states’ regular waves. The results show that increasing the number of buoys at a constant volume decreases the surge and pitch motion amplitude, while the heave motion increases slightly. Adding the buoy and clump weight (type 1) to the mooring line reduces the oscillation amplitude tension. In addition, raising the number of buoys increases the oscillation tension.
  • Falkowski-Gilski, Przemysław; Uhl, Tadeus (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Thanks to the availability of mobile devices and the spread of broadband access around the world, the number of network users continues to grow. This has raised user awareness when it comes to the quality of content they consume. Many service providers and operators focus on monitoring QoN (Quality of Network) and QoS (Quality of Service) parameters, particularly those influenced by bandwidth and latency. However, for most end-users, quality is understood as the subjective QoE (Quality of Experience), a mixture of several individual factors. This paper presents a QoN evaluation, carried out under real-time operating conditions at a university campus, considering the overall performance of the cellular network. The study involved 50 mobile devices, i.e., smartphones, used by students during their typical activity throughout a week. The results were gathered on the eve of 5G, using a custom-built Android application. This application enabled the acquisition of valuable data about the wireless link, including download and upload speed, latency (pink), the ID of the serving base station, and type of cellular connection. This approach can be used to detect the strengths and weaknesses of back-end networks.
  • Kasyk, Lech; Pleskacz, Krzysztof; Kapuściński, Tomasz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The definition of dynamic areas of searching for shipwrecks, and/or the movement of pollution across waters of Szczecin Lagoon first requires the knowledge and specification of hydro-meteorological conditions across the area. This article compares wind parameters from various sources of meteorological stations located close to Szczecin Lagoon. The wind speed and direction were obtained from Ueckermuende, I Brama Torowa (Urząd Morski Szczecin), and Kopice (wind meter of Szczecin Maritime Academy). Wind direction data analysis was based on directional statistics methods and tools.
  • Dembińska, Izabela (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    As the year 2022 has come, people expect much and are looking to achieve new goals and face challenges. We are happy to offer to you another issue of the Scientific Journals of the Maritime University of Szczecin. In this issue, we present views, opinions and research findings from different areas of research. Articles have been grouped into the following thematic sections: Civil Engineering and Transport, Material and Mechanical Engineering, Economics, Management and Quality Science and Information and Communication Technology. In Civil Engineering and Transport, there are two articles. The authors of the first study believe that the shoreline is an important geographical zone, and a better understanding of it could have key importance for shore management and creating maps. An analysis of methods for delineating the shoreline was made, where the focus of attention was accuracy. The second paper describes the mathematical formulas for the boundary element method (BEM) governing the dynamics of mooring with buoy equipment. The paper dealt with the semi-submersible FOWT OC4-DeepCwind platform. It was found that by properly selecting the volume and the position of a buoy on the rope the rope’s stress can be reduced by up to 45%. Material and Mechanical Engineering consists of two articles. In the first study, a functional diagram for an automatic sliding mode control system for a three-phase bridge buck current converter was developed. To achieve this, a simulation program was created in MATLAB/Simulink which analysed the dynamic performance of the developed automatic control system, operating in the active rectifier and network current inverter modes. The second article analyses the impact of gas turbine contamination on a drop in airflow, pressure ratio and compressor efficiency. The analysis was based on the assumption that the turbine contamination results in a decreased rated power of the gas turbine and an increased fuel consumption. The case of a shipborne MT30 gas turbine with a nominal power of 36 MW is used in the study. In Economics, Management and Quality Science, we present three articles. Authors of the first study have set out to determine the main conditions for cost-effective production of motor boats in Poland taking into account the implementation of an R&D project. A descriptive analysis was carried out to describe the market conditions for the operation of manufacturers of motor boats, including electric boats. The results obtained allowed defining changes in the business model based on the R&D project. The subject of consideration in the second paper of this section is the concept of a green port. The authors have analysed various initiatives and strategies for ports that are already called “green”. Recommendations based on the analysis are profiled specifically for the Port of Gdynia. The authors of the third study focused on the relationship marketing aspects of container transport. They believe that the strategic competitive advantage in this area of transport is no longer entirely dependent on the basic characteristics of the service provided, and that customer relationships are becoming more important. Authors conclude that container shipping lines must develop effective customer-oriented relationship marketing strategies. Guided by this view, the authors examined selected relationship marketing strategies that are practised in the container shipping industry. Information and Communication Technology presents a study, in which the authors explore the use of ontology for semi-automatic marine vessel navigation and ship-to-ship communication to mitigate collision risk. Examples of how such communication can be used are discussed, based on a comprehensive analysis of selected marine collisions, with particular attention to the communication conducted on ships. The effectiveness of such communication was assessed and compared. I am hoping that the studies presented will meet with wide interest implying discussions and research not only in the discussed research areas, but also going beyond them, giving a stimulus to interdisciplinary and heuristic analyses.
  • Idzior, Marek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In recent years, there has been an intensification of work on the autonomy of means of transport, which also applies to ships. Modern ships are already equipped with crew decision support systems and numerous diagnostic systems. Increasingly more systems are installed on ships that can operate without human integration. This situation leads to the development and use of fully autonomous ships. This overview publication briefly describes the main features of the construction and operation of autonomous ships, including some examples of structures already demonstrated in recent years. In summary, the author presents comments that provide a contribution to the discussion on the autonomy of means of maritime transport.
  • Nazemian, Amin; Ghadimi, Parviz; Ghadimi, Aliakbar (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Hydrofoils are utilized as instruments to improve the hydrodynamic performance of marine equipment. In this paper, the motion of a 2D NACA0012 hydrofoil advancing in water near the free surface was simulated, and a mesh morphing-adjoint based optimizer was used to maximize its lift-to-drag ratio. Ansys-Fluent was used as a CFD solver, and a mesh-morphing tool was used as a geometry reconstruction tool. Furthermore, the Adjoint solver was applied to evaluate the sensitivities of the objective function to all solution variables. Defined control points around the geometry are design variables that move in an appropriate direction through shape sensitivity. The computational results were validated against available experimental data and published numerical findings. Subsequently, different hydrodynamic characteristics of the optimized hydrofoil were compared to those of the original model at different angles of attack of 3, 3.5, 4, 4.5, 5, 5.5, 6, and 6.5°, and optimized shapes were determined. It was observed that the shape of the optimized hydrofoil was totally dependent on the angle of attack, which produced different lift-to-drag ratios. It is also seen that among higher angles of attack at which improvement in the L/D ratio became steady, the drag coefficient was the lowest at 5°. Therefore, it can be concluded that the appropriate angle of attack for a hydrofoil installation on the ship hull is 5°. Further investigation was conducted concerning the evolution of shape optimization, sensitivity analysis, free surface elevation, flow characteristics, and hydrodynamic performance of the hydrofoil at a 5° angle of attack.
  • Pawelski, Jan (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The grounding of a 400-meter long container vessel, called Ever Given, in the Suez Canal blocked the busiest shipping lane, which is responsible for 12% of seaborne trade, for 6 days. Some shipping companies had to divert their vessels and they had to take a much longer route around Africa to reach European ports. The concerned shipping industry started to look for alternative sea route to the Suez Canal with lesser risk of blockage, without a need to go around Africa. Such routes, which connect the Pacific and Atlantic Oceans, exist in the Arctic and the warming of the global climate makes them more accessible over time but the assessment of their viability requires a multifaceted analysis based on available professional navigational publications, scientific papers, and knowledge of polar shipping realities. Several nautical aspects are taken into account with the purpose of choosing a polar route that is most suitable as an alternative to the Suez Canal. Three routes are under consideration. One of them is the Northern Sea Route in the eastern part of the Arctic Ocean, along the coast of the Russian Federation. The second route is the Northwest Passage through the western part of the Arctic, passing waters belonging to Greenland, Canada, and the United States. The third one passes near the North Pole, a prospective route that may become available for commercial shipping in the future due to Arctic ice shrinkage, and it is known as the Transpolar Route. Analysis of these routes unambiguously point to the Northern Sea Route as the only viable option. Most prospective alternatives to the Suez Canal are technically feasible with the new generation of cargo vessels and they are experiencing a growth in maritime traffic together with a steady development of associated infrastructure. The existing simplified analyses of the transit costs, assuming strait passage in polar waters without any course deviation and the additional fuel that is burnt to overcome increased friction during passage in ice, shows that under present conditions that the Suez Canal Route is still cheaper than any polar transit and, moreover, offers year-round availability. It cannot be ruled out that the upcoming warming of the Arctic climate, and a lowering of the transit tariffs by the Russian Federation may tip the balance in favor of the Northern Sea Route. Presented here is an analysis of the competitiveness of the Arctic Routes in comparison to the Suez Canal from the perspective of the mariner.

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