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  • Pieniak, Daniel; Mańkowska-Snopczyńska, Anita; Walczak, Agata; Wąsik, Wiktor; Gil, Leszek; Selech, Jarosław; Žvirblis, Tadas (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    One of the main operational tasks of fire investigation units is to extinguish fires, which is most often achieved by applying various types of extinguishing agents to the burning material. For firefighting to be effective, it is essential to use appropriate equipment, including fire hoses through which water or water-based solutions are transported. Fire hoses must be resistant to mechanical, thermal, and chemical exposures. In particular, they must withstand abrasion, which can compromise tightness and result in leakage or uncontrolled water jets. Hose webbing typically has a multilayer structure. The outer (surface) layer is exposed to abrasion from sliding friction in contact with rough surfaces, sometimes containing abrasive particles. Abrasion against sharp edges occurs less frequently due to safety features such as fire hose saddles. Pilot laboratory tests were carried out on the hose webbing of four fire hose models to determine the coefficient of friction and linear wear. Additionally, observations were made on the wear mechanisms affecting the hose webbing surfaces.
  • Jachowski, Jacek; Książkiewicz, Edyta (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    The success of a search and rescue operation at sea depends on accurately determining the location and search area of a drifting pneumatic life raft, with particular emphasis on drift. This article examines the leeway of pneumatic life rafts and provides a summary of the available types used as life-saving appliances on ships. Based on experimental and numerical studies, the technical characteristics of the life rafts were compared, and the relationship between their shape and leeway components was analyzed. The research demonstrated the degree of dependence between the life raft’s shape and its aerodynamic and hydrodynamic drag. The results obtained are significant and will inform further numerical studies on leeway and search area estimation. The authors’ previous experimental and numerical work, as well as findings from earlier publications, form the basis for the calculations presented in this paper.
  • Barczak, Agnieszka (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    Intermodal transport is a key element of the Trans-European Transport Network (TEN-T), and containers are among the most commonly used cargo units in this system. This study aims to examine the development trends in container handling at intermodal terminals in Poland. The results of the study indicate continued dynamic growth in this sector, supported by European Union policy, infrastructure investments, and the expansion and construction of new container terminals, as well as the activities of logistics companies and intermodal carriers. Projects co-financed by EU funds also play an important role, providing an additional stimulus for development.
  • Kozak, Maciej; Głogowski, Piotr; Kozak, Marcin (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    Abstract This article addresses the problem of sensorless control of a squirrel-cage induction generator (SCIG) used as a shaft generator in shipboard DC power systems. The work is motivated by the growing adoption of DC ship- board microgrids, where robust and cost-effective generators without mechanical sensors are desirable. A math- ematical model of the SCIG in α-β and d-q reference frames is derived and discretized, enabling efficient re- al-time implementation on a DSP–FPGA control platform. Building on this model, the paper proposes a hybrid current–voltage observer that combines a current-model estimator (effective at low speed) with a voltage-model estimator (accurate at medium and high speed). PI-based compensating voltages are introduced to suppress numerical integration drift and reduce sensitivity to stator resistance variation, ensuring accurate estimation of rotor flux, flux angle, and rotational speed. The excitation process of the generator is analysed with respect to initial DC-link voltage, shaft speed, and loss currents, and criteria for successful self-excitation are identified. The proposed algorithm is validated through time-domain simulations and laboratory experiments on a 3 kW SCIG system. Results show close agreement between simulation and measurements, stable DC-link voltage regulation under varying load and speed, and reliable sensorless operation that is comparable to, or more robust than, encoder-based systems in the presence of EMI. The study confirms the practical suitability of the hybrid observer for shipboard SCIG applications over a wide rotational speed operating range.
  • Kokorniak, Anna; Gabriela-Półrolniczak, Urszula (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    Faced with the European Union’s growing expectations regarding the intensification of energy generation from renewable sources, Poland, like many other European countries, has encountered the enormous challenge of introducing energy produced by offshore wind farms (OWFs) into the energy market. This article aims to present the current state of development of offshore wind farms (OWFs) in Poland and to identify the main opportunities and threats associated with the further development of this sector in the domestic and international context. The direction of the current rapid investment growth in this area stems from decisions of the European Parliament and the European Council, which require intensified efforts to increase the share of energy obtained from renewable sources in the energy mix. At the same time, the creation of an energy base in the form of offshore wind farms in Poland contributes to energy diversification and improves the country’s energy security. Several projects are currently underway in the Polish Baltic Economic Zone, the largest of which include Baltica 2 and Baltica 3, led by PGE Polska Grupa Energetyczna and the Danish company Ørsted. The construction of offshore wind farms encounters several barriers that hinder project implementation; however, long-term energy production can bring numerous benefits to Poland. This paper highlights the key advantages of offshore wind farm development, including Poland’s energy sovereignty, job creation, and strengthened efforts to reduce greenhouse gas emissions. The greatest threats, however, include an underdeveloped local supply chain, unpredictable legislative changes, and the risk of delays due to environmental requirements. Considering the limitations associated with the lack of production continuity and the ability to fully utilize the electricity generated by offshore wind farms, solutions for industrial-scale electricity storage are presented, including conversion to compressed air using compressed air energy storage (CAES) technology, and the conversion of electricity into chemical energy in the form of hydrogen (H2).
  • Marzantowicz, Łukasz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    The main objective of this article is to demonstrate the impact of uncertainty on the resilience of supply chains. To achieve this task, a theoretical discourse is presented on both uncertainty and supply chain resilience. A survey is conducted among 160 supply chain managers and directors from around the world. The survey utilized the computer-assisted web interview (CAWI) method, and the results are analyzed using the Ward agglomeration method. The findings enabled a determination of the strength of uncertainty’s impact on supply chain resilience, understood through the so-called 4A formula, which combines flexibility, adaptability, resilience, and alignment. Additionally, the article discusses whether these considerations can contribute to supply chain management, particularly in supporting decision-making processes, such as the supply chain’s response to uncertainty. This study is the author’s original work and represents their contribution to the ongoing scientific discussion on the resilience (including response) of supply chains under conditions of uncertainty.
  • Olejnik, Krzysztof (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    In Poland, the introduction of absolute priority for pedestrians at crosswalks in traffic regulations may increase the number of accidents. Improved traffic control of intersecting routes may be a more effective solution. The recent amendment to the law overlooks the fact that a moving vehicle cannot stop immediately. The dynamics of vehicle stopping, especially before a pedestrian crossing, must be taken into account. This article analyzes possible road scenarios encountered when approaching a pedestrian crossing. Pedestrians at crosswalks should be safe and protected. While granting pedestrians the right of way is an ideal scenario, certain situations may still pose risks to their safety. Proposed solutions to reduce the risk of accidents for pedestrians entering the crossing are also included. The introduction of appropriate signaling, along with a selected algorithm and sensors, can help alleviate the danger to pedestrians. Additionally, the system should identify when a bus is approaching the pedestrian crossing and monitor adverse weather conditions that reduce a vehicle’s ability to stop abruptly
  • Woźniak, Marek; Morawski, Jakub; Zakrzewski, Sergiusz; Kądziela, Arkadiusz; Siczek, Krzysztof (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    This study aims to determine the effect of loading on stress distribution in components of the scissor lift during the pushing up or down of the car being analyzed. The FEM models of the lead screw and the lift arms are elaborated and implemented using both Autodesk Inventor and the Solid Edge software. The mathematical model for the lead screw is also developed. The models allowed for the obtaining of the von Mises stress values in the lead screw and in the lift arms. Such stress values in the middle of the FEM screw model coincided with those determined analytically. The obtained values are very sensitive to the level of refinement applied for the size of finite elements. The values of the von Mises stresses in both lower and upper arms varied depending on the lift. For a small value of the lift, they can be up to 35% higher than those in the lead screw. However, for the higher lift, the von Mises stress values in the arms may be equal to or smaller than those in the lead screw.
  • Kaśkosz, Karolina; Duma, Marianna; Lemke, Justyna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    In an era of constantly changing needs and challenges posed by urban stakeholders and an increasing number of vehicles in the area, transport accessibility has started to play a key role. Shaping transport infrastructure in cities is one of the greatest challenges city managers have. In recent years, the introduction of paid parking zones (PPZs) has become an increasingly common solution. This paper aims to assess the impact of parking fees on the mode choice of users of urban spaces. As part of the research process, a systematic review of literature in the area outlined above and an analysis of transport accessibility in the selected area are carried out. This paper presents the results of a survey on the determinants of transport mode choices in the city of Szczecin. The results show that, despite high rates imposed by city authorities, users of urban spaces still choose to travel by car to their destinations and that parking fees do not have a real impact on modal shift. These results offer valuable insights for both drivers and local authorities in terms of creating transport accessibility for the final stage of this journey ‒ i.e., parking accessibility.
  • Abuelenin, Ahmed Hany M. (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    The maritime transport of dangerous goods (DG), including hazardous and noxious substances (HNS), poses escalating environmental and legal challenges, particularly in Southeast Asia’s high-traffic corridors. While international frameworks such as UNCLOS, MARPOL, and the IMDG code impose clear obligations, ASEAN member states exhibit fragmented implementation and limited HNS-specific preparedness. This paper critically assesses the region’s regulatory landscape through a legal-doctrinal and theoretical lens, identifying gaps in treaty ratification, port state control, and regional cooperation. It argues that soft-law mechanisms and institutional inertia undermine effective risk governance. This study calls for a binding regional instrument on HNS response, harmonized inspection regimes, and integrated liability frameworks to align ASEAN practices with global marine protection standards. Accordingly, the purpose of this work is to examine how ASEAN’s approach to DG transport aligns with international maritime law and to propose reforms that strengthen both regional and global marine environmental governance.
  • Romankiewicz, Remigiusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    AlSi9Mg silumins are increasingly used in lightweight ship structures and onboard equipment, where resistance to impact and vibration is crucial. This study evaluates the effect of AlSr10 (0.15 and 0.30% Sr) and AlB4 (0.20% B) additions on the microstructure, impact strength and fracture behavior of the AlSi9Mg alloy. The highest improvement in impact strength—from 4.8 to 11.1 J/cm²—is achieved with 0.30% AlSr10. The lamellar eutectic β(Si) transformed into a fine fibrous morphology, reducing interphase spacing and producing a more tortuous fracture profile, which enhanced dynamic load resistance. While the AlB4 addition shortened α(Al) dendrites, it did not significantly improve impact strength (4.13 J/cm²). The results demonstrate that a properly selected Sr level enables the design of components (e.g., brackets, housings, and guards) for marine environments subjected to impact and vibration. This work provides a basis for future investigations into long-term durability of modified silumins under corrosive marine conditions and combined impact–vibration loads specific to waterborne transport.
  • Tabor, Joanna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    The purpose of this study is to propose and verify the feasibility of using gray relative analysis (GRA) to identify key characteristics of an industrial maintenance system and key factors for managing human reliability in this system. The developed approach is verified using qualitative and quantitative data obtained from seven companies in the furniture industry. Through the approach used, the following maintenance characteristics are identified as key: scheduling intensity index, work scheduling intensity index, and work request response index. In addition, the following human reliability management factors are identified as key: analysis of error reduction measures, implementation of error reduction measures, and evaluation of the effectiveness of implemented human error reduction measures. The approach verified in this paper is computationally simple and beneficial in cases of imprecise and incomplete information and small sample size, while the results obtained are easy to interpret. This approach can, therefore, be a crucial tool for improving enterprises in maintenance and in terms of improving human reliability. The application of GRA in human reliability management in industrial maintenance is original.
  • Durlik, Irmina; Miller, Tymoteusz; Kostecka, Ewelina; Sokołowska, Sylwia; Kostecki, Tomasz; Zwolak, Rafał (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    In this article, we delve into the fusion of machine learning (ML) and Internet of Things (IoT) technologies to redefine environmental radiation monitoring and security. By harnessing these advanced technologies, this work presents a novel approach to radiation safety, emphasizing enhanced real-time monitoring, precision in detection, and improved regulatory compliance. Through an in-depth analysis of various case studies and methodologies, it uncovers the potential of ML and IoT in overcoming traditional challenges, such as data accuracy and privacy concerns. The discussion extends to the implications of these technologies on environmental safety, offering a forward-looking perspective on the evolution of radiation monitoring systems. This article not only addresses the technical and ethical challenges but also highlights the transformative impact of ML and IoT integration on public health and environmental protection, paving the way for innovative solutions in the domain of environmental safety and security.
  • Jagusiak-Kocik, Marta (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    This paper aims to present the potential for integrating the classic Kano method with artificial intelligence tools to support customer needs research and segmentation for manufacturing companies. This research provides a literature review of the Kano method and AI technologies used to analyze customer data. A case study conducted at a Polish manufacturing company in the SME sector explored ways to better align offerings with market expectations. The study is based on identifying product features and developing a Kano questionnaire, followed by the use of popular chatbots (i.e., ChatGPT, Copilot, and Gemini) to automatically assign these features to the appropriate Kano model categories. The data originates from online surveys and direct contact at points of sale. The results of the automated analysis are compared with traditional results, assessing the compatibility of both approaches. The paper demonstrates that integrating these two methods significantly improves the decision-making process for product development, increasing the precision of customer needs identification and the effectiveness of implemented innovations.
  • Michalik, Joanna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Politechniki Morskiej w Szczecinie, )
    Motivation is a key element of effective human resources management in virtually every industry. Properly motivated employees are more engaged, productive, and loyal to the organization. The purpose of this article is to demonstrate the importance of employee motivation as a key element of the organizational management process, with particular emphasis on its impact on work efficiency, team engagement, and the achievement of operational and strategic goals. This article also examines various motivational tools and models used in selected economic sectors (i.e., services, manufacturing, utilities, and transportation). It compares motivational practices across sectors, identifying similarities and differences, and indicates which mechanisms are most effective under specific conditions, which constitutes the author’s scientific contribution. It also presents factors that influence employee motivation in enterprises across various industries. A survey has been developed for this publication, in which employees responded to questions regarding the impact of management behavior on motivation. Based on the author’s own observations and survey questions, the motivational needs of employees in a manufacturing company and the transportation industry in the Silesian Voivodeship are analyzed.

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