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  • Magryta-Mut, Beata (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This study aims to improve an earlier safety analysis of port and maritime transportation systems in two cases. The first case does not consider outside impacts and the second case operates under the assumption that they are impacted by their operation processes. New and original suggestions on separate and joint system safety and operation cost optimization are also described and future research is also outlined. Probabilistic modeling methods are used as the research methods. The proposed research procedures enable the determination of the safety function and risk function for the port oil terminal critical infrastructure and the maritime ferry technical system in both examined cases, based on the strictly exact statistical data about their operation processes and on the improved approximate evaluations of their components safety parameters through expert opinion methods that originate directly from the users of these systems. Other proposed practically significant safety and resilience indicators are the mean lifetime up to the exceeding of a critical safety state, the moment when the risk function value exceeds the acceptable safety level, the intensity of ageing/degradation in both cases, the coefficient of operation process impact on system safety, and the coefficient of system resilience to operation process impact in the second case. As a result of this research, it is originally found that the proposed cost optimization procedures and the finding of the corresponding system safety indicators deliver an important possibility for the system total operation cost minimizing and keep fixed the corresponding conditional safety indicators during the operation. It was also established that the proposed system safety optimization procedures, and corresponding system operation total costs, deliver an important possibility for the system safety indicators maximization and keep fixed the corresponding system operation total costs during the operation.
  • Kacprzak, Paweł (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Experienced ship roll during loading is the easiest parameter to observe and measure on board of a loaded ship. Therefore, the ship’s significant roll amplitudes should be the key limiting factor in view of the safety and efficiency of cargo handling operations at sea. For the example of three standard bulk carriers, the authors prepared a method of assessment of bulk carrier suitability to perform safe and efficient cargo handling operations in the Clarion-Clipperton Zone in view of significant amplitudes of roll. Via a calculation of the efficiency index for a set of limiting amplitudes of roll during loading simulation, we are able to analyze ship effectiveness. The application of the above-mentioned method can be employed as a useful tool to predict the lowest allowable significant amplitudes of roll when the required efficiency level is specified. Additionally, a calculation is made for the operable days where cargo operations are possible. Investigations show that, according to applied criteria, the effectiveness drops, and not every bulk carrier can perform safe cargo handling operations at sea.
  • Bukowska-Pietrzyńska, Agnieszka; Motowidlak, Urszula (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article concerns the increasing complexity and variability of the business environment and the challenges faced by enterprises that operate within supply chains to properly identify and anticipate disruptions and adequately respond to them (i.e., the ability to resist and rebuild). This article aims to identify and evaluate the importance of the main factors that determine supply chains’ adaptability in the modern economy. A review of the literature on the subject, and the results of a survey conducted in the third quarter of 2022 among entities from the transport forwarding logistics (TFL) industry, diagnose the determinants of the adaptability of supply chains that operate when there are disruptions. They indicate the challenges faced by TFL companies that result from the COVID-19 pandemic and the war in Ukraine and the directions of changes that result from them, both from the short-term and strategic perspectives. The relationships between the development of adaptability of supply chains and the increase in the competitiveness of entities enable us to verify the research hypothesis that, in the face of increasing disruptions and uncertainty in the business environment, strengthens the adaptability of supply chains producing a great potential in terms of maintaining the competitiveness of enterprises in the TFL industry. To gain and maintain a long-term competitive advantage, companies should strive to create a resilient supply chain that can withstand challenges and disruptions.
  • Garczyńska, Ilona (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The conducted review presents the possibility of using artificial neural networks in sectors related to environmental protection, agriculture, forestry, land uses, groundwater and bathymetric. Today there is a lot of research in these areas with different research methodologies. The result is the improvement of decision-making processes, design, and prediction of certain events that, with appropriate intervention, can prevent severe consequences for society. The review shows the capabilities to optimize and automate the processes of modeling urban and land dynamics. It examines the forecasts of assessment of the damage caused by natural phenomena. Detection of environmental changes via the analysis of certain time intervals and classification of objects on the basis of different images is presented. The practical aspects of this work include the ability to choose the correct artificial neural network model depending on the complexity of the problem. This factor is a novel element since previously reviewed articles did not encounter a study of the correlation between the chosen model or algorithm, depending on the use case or area of the problem. This article seeks to outline the reason for the interest in artificial intelligence. Its purpose is to find answers to the following questions: How can artificial neural networks be used for spatial analysis? What does the implementation of detailed algorithms depend on? It is proved that an artificial intelligence approach can be an effective and powerful tool in various domains where spatial aspects are important.
  • Gnaciński, Piotr; Muc, Adam; Pepliński, Marcin (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The presented study examines the effect of voltage subharmonics, which relates to components of the frequency less than the fundamental voltage harmonic, and the currents and vibration of the line start permanent magnet synchronous motor. The obtained experimental results corresponded to a production motor with a rated power of 3 kW and a rated speed of 1500 rpm. The main purpose of our study was to highlight that the subharmonic value had a non-linear effect on the vibration level of the considered motor. It was found that for subharmonic values up to approx. 0.5% of the vibration level could be considered acceptable for long-term operation, whereas vibration caused by voltage subharmonics of values greater than approx. 0.8% might promote machine damage.
  • Dydkowski, Grzegorz; Urbanek, Anna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The main purpose of this paper is to investigate the impact of fare integration on the demand for public transport and the role of IT technologies and cash-free payments in this process. The paper presents the results of a critical literature review of studies conducted in this area so far. This approach enables the integration of theoretical and empirical findings, and perspectives of fragmented and interdisciplinary studies. Fare integration in cities is one of the factors that increase the demand for urban public transport services. This results from an improved image of public transport, easier promotion of services, more eligible passenger information, and easier use of services due to the uniform regulations and fares. In addition, for travelers, fare integration means cheaper services because they do not need to buy separate tickets corresponding to various organizers or carriers. The implementation of solutions from the field of fare integration is also related to costs; one can primarily mention the transaction costs and those related to the introduction of new solutions into the sales systems. The increase in the demand for public transport services due to the implementation of fare integration, results in external benefits that affect the sustainability of city transport systems and, thereby, justifies the funding of it by the public sector, which is accountable for ensuring efficient public transport.
  • Bojanowska, Milena (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Rapeseed by-products of seeds de-oiling, particularly expellers and post-extracted meal, are currently considered an important biomass that can be used as an alternative energy source, either in raw form or after conversion to biochar. Rapeseed biomass represents a difficult-to-handle cargo, mainly due to its sensitivity to mechanical, climatic, and biological impacts, as well as its dusty nature. This study aims to determine the physical properties of rapeseed meals and their fractions. Morphological and chemical features of six particle sets are investigated in order to explain the variation in their physical properties having importance in handling and transportation processes. The true density of fractions increases when the particle size decreases due to the diminishing quantitative share of seed coats. No correlation is observed between true and bulk densities, as the particle shape, surface sculpture, and adhesion affect the mutual particle arrangements. Along with a decrease in the particle size from 0.4 mm, a rapid decrease in the flowability is observed. The tendency of the finest dust (d < 0.075 mm) to form agglomerated complexes causes its lower bulk density, higher porosity, and higher angles of repose in comparison to coarse dust (0.075–0.4 mm). It is concluded that a relatively low tendency to free flowing of natural RSM is mainly caused by its wide-ranging particle size distribution and their geometry differentiation, which facilitate mutual particle interlockings. The known cases of blockages of silos, bins, hoppers, and transfer chutes may be mainly caused by the powder fractions (< 0.2 mm), with a much lower flowability than other particles.
  • Revenko, Vitaliy Yu. (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The effects of precipitation of varying intensity on the operation of a ship’s radar are considered. It is shown that during the propagation of the electromagnetic wave emitted by the antenna of a ship’s radar, its energy is absorbed by precipitation. To determine the power loss of an electromagnetic wave due to its absorption by particles of precipitation, the effective absorption area, specific absorption coefficient, and specific effective total scattering area are used. The effective areas of absorption and total scattering depend on the shape of the precipitation particles, their size, state of aggregation, and the length of the electromagnetic wave emitted by the antenna of the ship’s radar. The dependence of the effective absorption area on the particle size of precipitation is obtained at two wavelengths of 3 cm and 10 cm, on which the ship’s radars operate. A decrease in the tracking range of an object tracked by a ship’s radar in the case of rain falling is established compared with the tracking range of an object in clear weather. It is shown that a decrease in the tracking range of an object occurs only with moderate, strong, and very heavy rain. The attenuation of electromagnetic energy in rain with an intensity of 12.5 mm/h at a wavelength of 3 cm is obtained by calculation, which amounted to 24 dB with a length of the falling rain zone of 50 km, as well as with rain with an intensity of 100 mm/h with the same length of the precipitation zone.
  • Mielniczuk, Sylwia (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper proposes a modified artificial potential fields (APF) method for collision avoidance at sea. The concept of artificial potentials used herein is derived from fields generated by electric charges. Attractive and repulsive forces are determined, accounting for the positions of an own vessel and a target vessel. The own vessel and its goal are considered as opposite charges. There is an attractive force between them, while the own vessel and target vessels or obstacles are considered as charges with a repulsive force between them. The values of these forces depend on the coefficients of attraction and repulsion. To solve a particular collision situation, the modified method of artificial potential fields is used. Due to the specific nature of the vessels’ movement, additional factors affecting the values of the attraction and repulsive forces are considered, as opposed to solutions used for robots. The main purpose of this article is to present the method for determining the coefficients of the APF method. This method will be used to avoid collisions at sea. From an analysis of factors influencing the execution of the vessel maneuver in a collision situation, a modified method for determining the attraction and repulsion coefficients is proposed. A case study of collision avoidance in a vessel encounter situation is also conducted.
  • Stopa, Michał (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In recent years, a significant emphasis has been placed on the technological side of shipping. However, humans remain the operator of the vessel and the ones to make the final decision. With the increasing problem of fatigue, a properly designed bridge might offer great support for navigators. This includes the implementation of ergonomics in the workplace. This paper aims to better understand the needs of end-user operators and determine if there is still a need for improvement in bridge ergonomic design. To reach this goal, a custom-designed questionnaire survey of 200 professional navigators is performed. The Kano model is used to analyze the seamen’s wants and needs, but also expectations based on their satisfaction with proposed ergonomic solutions. The research results suggest that there is still room for improvement in this area, which is not only a matter of comfort or health but also safety.
  • Falkowski-Gilski, Przemysław; Uhl, Tadeus (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The COVID-19 pandemic has significantly limited user mobility, not least among students. Remote learning had a particular impact on resource allocation in relation to using terrestrial cellular networks, especially 4G systems in urban agglomerations. This paper presents the results of a quality evaluation of an outdoor environment, carried out between 2019 and 2021 on the campus of a technical university. Annual studies are conducted using our own custom-built mobile application, installed on 50 mobile devices (i.e., smartphones) running Android OS. This study aims to determine the impact of reduced user mobility on access parameters in mobile networks, that is, both download and upload throughput as well as delay (ping), with a particular focus on serving base transceiver stations (BTSs). This research scenario involves long-term evolution (LTE) compatible user equipment (UE) that operates under four Polish mobile network operators (MNO), which includes roaming connections and the newly launched 5G standard.
  • Jeleniewicz, Katarzyna; Rutkowska, Gabriela; Żółtowski, Mariusz; Kula, Dorota (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Caring for the environment, in accordance with the principles of sustainable development, as well as the increase in the standard of living of society, introduces the need to conduct proper waste management. Construction is an industry with great potential for the management of glass waste as part of material recycling. The construction sector is characterized by high material consumption, with a limited amount of natural resources, meaning that research is constantly being performed on the possibility of replacing them with other common ingredients. A feature of the building materials industry is also the pursuit of continuous improvement of the properties of manufactured materials. The paper presents the research results on the impact of the partial replacement of Portland cement and aggregate with glass waste on strength parameters and frost resistance. For the purpose of experimental work, a concrete mix based on the C20/25 standard concrete with CEM I 42.5R Portland cement, in which from 0 to 20% of the cement or aggregate weight is replaced with glass waste (i.e., glass flour and glass cullet), is designed. In the test range, the glass flour slightly affected the deterioration of the compressive strength, while the glass cullet had no effect on the compressive strength after 56 days of maturation. Moreover, the addition of glass flour increases the bending strength, while the addition of glass cullet maintains a comparable bending strength compared to the reference concrete. The obtained concretes are frost-resistant concrete F150.
  • Dębicka, Olga; Reszka, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    A period of pandemics and distance learning has forced teachers to plunge headlong into the technological challenges of education. Today, it is possible to look back on this time as an educational milestone that, although forced, contributed to a much-needed leap into the digital age in higher education. Information and communication technologies (ICT) have contributed to a significant paradigm shift in learning and the roles of teachers and students in education today. ICT tools in the educational process have become indispensable, whether for on-site teaching, an exclusively online system, or a hybrid scheme. Therefore, this study aims to establish how modern technology has enabled a unity of resources in the education process and to identify how the pandemic conditions have affected the logistics process for didactics, particularly related to providing a unity of the right resources in the correct place. Moreover, the authors indicate the benefits of the described changes in the didactic process for teachers and students in the post-pandemic period.
  • Kaizer, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The main purpose of dredging is to maintain the required depth of harbors and marine and inland waterways. Any investment work in port infrastructure should be planned in such a way as to minimize interference with the port operations and vessel traffic. The research aims to analyze work scenarios involving a proposed dredging fleet using a Navi-Trainer Professional 5000 navigational and maneuvering simulator connected to the Transas Navi-Sailor 4000 navigation information system. An analysis performed using these electronic chart display and information system (ECDIS) simulators allows the operational parameters of the dredging project to be determined. These parameters include driving time, time taken to fill a TSHD dredger to full capacity, scale of maneuverability of the dredger within the port area, and determination of the safe distance between dredging vessels and other ships. The proposed solution may be supplemented with additional computer-based programs, providing a valuable tool in the research and monitoring of planned and current dredging projects.
  • Mocek, Piotr (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The article presents the results of measurements of environmental noise caused by devices operating in the surface facilities of hard coal mines and by the technological processes related to the loading and transport of spoil and materials necessary for production. The research results are part of the program “Consequences of excessive noise in the mining environment of hard coal mines”, the overarching goal of which is to reduce the emission of industrial noise. A sampling method was used to determine the actual values of noise levels emitted to the external environment from mines and mining plants as well as to identify the acoustic power levels of devices and processes constituting the main sources of noise in mines. The results showed that mines and mining plants are often not fully aware of the scale of the environmental impact of the undesirable noise they emit. Therefore, the current periodic measurements of environmental noise should be replaced with permanent monitoring, which will be beneficial not only for the environment and residents of housing estates located near mines but also for the mining plants themselves.

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