Dear Readers, We are pleased to present you the last issue of our Scientific Journals of the Maritime University of Szczecin in this year. In this last edition, you will find twenty-two articles addressing topics from a wide variety of research areas. They have been grouped into the following sections: Civil Engineering and Transport, Material and Mechanical Engineering, Environmental Engineering and Mining, Power Engineering, Sustainability and Smart City, Economics, Management and Quality Science. We are pleased that the manuscripts submitted to us cover such a broad research field. This allows us to offer our readers a multi-disciplinary spectrum of research problems.

The Covid-19 pandemic has affected all aspects of human life. Its negative effects have also hit the transport industry, largely as a result of staff contracting the virus and the restrictions imposed on human mobility. Therefore, the purpose of this study is to establish how the situation of rail freight transport in select EU countries has evolved in the post-pandemic era. The trend of rail freight transport is presented for the years 2015–2021, and forecasts are made for the years 2020–2021 using the method of seasonality indices. The study results show that most of the investigated countries show adverse differences in the actual and forecast quantity of freight handled, an effect clearly attributable to the pandemic.

This article presents an analysis of the static loads on the human body during selected manual unloading tasks carried out by warehouse workers in a logistics company. The aim of the presented analyses is to minimize static loads in the work process and thus make the employees’ work more comfortable. A tool in the form of 3D SSPP software for ergonomic workload assessment was used to carry out static load analyses. For the two selected activities, the values of the developed forces of statically working muscles and the forces acting on the vertebrae of the spine were determined. For the values of static loads identified, based on the simulation of the 3D SSPP program, modifications in work posture and a change in the manner of performing the tested activities were devised. Moreover, the proposed reorganization of the tasks examined was verified by the reassessment of the static loads on the muscles using the 3D SSPP tool. The analyses carried out after the reorganization of work confirmed the reduction in static loads and the improvement in work comfort for the analyzed manual tasks.

Flight training is occupied by many hours of theoretical and practical training. Polish universities offer the possibility of conducting the aforementioned training as part of academic training. A young aviation student, implementing himself in this process, takes on the burden of academic training and aviation training. The aviation environment is sensitive to safety issues. These include the occurrence of incidents, events, and aviation accidents. This issue arises directly from the possibility of endangering the health and lives of bystanders as well as aviation personnel and the damage or destruction of aviation equipment. In addition, there are issues related to the immobilization of airports, aviation organizations, excess repairs, or cases settled in court. Despite all the above, it should be mentioned that air transport is described as the safest means of transportation where – although incidents, events, or high-profile crashes are occasionally recorded. It is desirable for personnel to remain as focused as possible during aviation tasks. The multitude of tasks carried out by aviation students, combined with the burden of academic study, can carry a significant impact on maintaining concentration, lowering perception, or at least meticulousness. These topics correlate closely with the human factor. As a research problem, the submitted work was adopted to determine the impact of academic teaching load on the safety of aviation activities performed, in the context of aviation training provided at universities. The research included aviation mechanics and aircraft crews within its scope.

Today’s shipping industry is experiencing a shortage of properly trained and competent deck and engine officers. This problem is becoming more acute with each passing year and traditional methods to resolve it apparently do not work. It has become obvious that cargo vessels must be less dependent on human operators. The solution lies in the replacement of manned vessels with autonomous ones. The introduction of autonomous vessels encounters several barriers, which need to be analyzed to find ways to overcome them. It requires a multipronged analysis of existing regulations, technical limitations, cyber security, and co-existence of manned and unmanned vessels in waters with dense traffic. The most difficult problems lie in international regulations, which were written for manned vessels only. Such rules need to be reworked before the deployment of autonomous vessels can be sanctioned worldwide. Technical issues are being gradually resolved with the introduction of new technologies. Special attention should be given to the cyber security of autonomous shipping as it requires the transfer of very large amounts of data through wireless networks. Accommodation of manned and unmanned vessel traffic may require a new approach for ship routing to separate both kinds of traffic.

The paper presents a new approach to the evaluation of human factor (HF) influence on the risk of maritime accidents. This approach is based on a formal human–ship–environment system definition including the relationships between humans, technology, environment, and organization. Social and organizational factors have already been included in the International Maritime Organization regulations; however, the individual factors still need investigation. A combination of psychological studies and technical operations of sea-going ships has given a huge opportunity to use HF assessment in rule-making processes. The main scientific goal of the research presented in the paper was the development of a method to assess the influence of HF on the risk of maneuvering accidents in restricted waters. This method is based on research within the area of technical ship operation and the results of the psychological profile of operators. The proposed model is based on a quantitative HF model developed by an authorized psychologist comprising personality traits, vulnerability to stress, and risk approach. The investigations were carried out with a group of 32 experienced ship masters performing a complex maneuvering task on the Full Mission Ship Handling Simulator. The multidimensional dependencies between variables of the psychological profile and the risk of an accident resulting from maneuvering errors were implemented into the Sugeno fuzzy model. The developed model allows risk assessment to be conducted that depends on the selected personality profile features. These features can be measured using psychological questionnaires, and then the risk of an accident due to maneuvering error can be calculated for a captain or marine pilot in order to improve human resource management.

For many reasons, ship model interaction tests are performed in experimental towing tanks. This paper presents research on the hydrodynamic forces acting on a ship tied up at the solid berth, which is produced by other ships passing by using free-running ship models with much larger dimensions than those used in towing tanks. A passing ship model was controlled by a human operator – an experienced master. This enabled a study of the influence of the interaction impact on the course of the maneuver. The research was carried out at the Ship Handling Research and Training Centre in Iława. The ship model was moored alongside and equipped with multi-directional force sensors linking the ship model with a solid berth. Forces were measured as a function of the passing ship speed, side distance between both ships, ship sizes, and depth-to-draft ratio (H/T). Forces were measured in two planes: the longitudinal (surge) and the transversal (sway). A numerical database was processed and ordered according to the variables. The fuzzy model was created within a “Matlab” computing environment using a Sugeno-type self-learning neuron network model. The proposed Sugeno model was evaluated with other methods presented by Flory (2002), Seelig (2001), and PASS-MOOR by Wang (1975). The ultimate goal of this study was to simplify the method of predictive calculations for adjusting speed and distance when passing by the moored ship, which ensures compliance with safe port mooring requirements.

Inland waterway transport (IWT) is currently in focus for EU countries due to a shift in policy towards a more sustainable and green economy. The aim of this article is to analyze the possibility of using a grey incidence analysis (GIA) to identify key factors related to the functioning of the IWT system. GIA is classified as a multi-criteria decision-making method and is one of the key applications of grey systems theory (GTS), i.e., systems with incomplete and uncertain information about structure and behavior. GIA identifies the most favorable (or quasi-preferred) system characteristics and the most favorable (or quasi-preferred) system factors. The identification of such characteristics and factors enables a reduction in the inconsistencies in decision making on the functioning of the system. The application of the GIA to the assessment of the IWT system is an original concept.

The solution of the nonlinear equation for a ship’s rotational motion around its longitudinal axis, even with simplifying assumptions, is complicated. This oscillatory motion, which is known as the roll motion, is generated when the ship sails in the waves, and the irregular behavior of the waves causes time-varying dynamics. Calculating the ship’s roll response is possible by determining roll equation coefficients. In the current study, the coefficients were determined from the dynamic response of the ship using a training feed-forward neural network. The training was carried out in two modes: as a free swing in calm water and forced oscillation in irregular waves. The DTMB 5415 vessel was selected as the case study ship. The results of the simulation by the neural network were validated by numerical analysis and model test results.

This article aims to compile, describe and compare three different models taken from the literature describing the causes of explosions in the crankcases of marine engines. Each of the models has a different level of detail and was prepared with a different purpose. However, the same process, explosions in crankcases, was analyzed in all cases. A statistical evaluation of the frequency of events leading to explosions, a model built using failure mode and effects analysis (FMEA) and a model based on fault tree analysis (FTA) are described in turn. The FTA model drawn from the literature formed the basis for further analysis. Values of important measures of all elementary events of the fault tree were calculated using the Birnbaum reliability measure, Vesely-Fussell measure, Birnbaum structural measure, criticality measure and improvement potential. The percentage importance values of all events determined using these importance measures were compared. The results obtained from the application of each model were evaluated. The results of the models were compared with each other, and an approach using all three models supplemented with diversion analysis was proposed.

Due to the high demand for secondary alloys in the automotive and aerospace industry, this work investigates the effect of higher iron content on the quality of AlSi7Mg0.6 sand castings. Secondary-recycled Al-Si alloys contain an increased amount of impurities due to their remelting of scrap metal. One of the most unwanted impurities found in these alloys is iron. Iron leads to the formation of various Fe-rich intermetallic phases, whose morphology influences the mechanical properties even at low Fe content. It also promotes the formation of casting defects, such as porosity and shrinkage. The formation of porosity in secondary Al-alloys is another major aspect that can affect the final properties of castings. Since these materials are mainly used to produce castings for the automotive industry, such as engine blocks, cylinder heads, and so on, it is necessary to produce castings without any defects. Therefore, the quality of AlSi7Mg0.6 sand casting is investigated at lower iron content (0.128% wt. Fe) and compared to the higher iron content (0.429% wt. Fe), whereby a correlation between iron content and porosity is monitored.

This article presents results for the development of new methods of inserting discontinuity lines into the numerical model of the deposit in CAD systems. The main problem in creating a numerical model of the deposit is usually a very small number, as well as low reliability of the source data. Hence, the authors developed new algorithms for inputting discontinuities, which can be used in particular for conditions when a large number of discontinuities are present. The article offers algorithms for inputting discontinuities into the entire deposit model. The method of transferring faults from the higher seam to subsequent seams and determining the course of the fault in the entire rock mass has been described. The fault can be represented as a spatial mesh of triangles, just like the seam floor. Then the fault can be extended until it intersects with the next seam (with the next triangle mesh) using geostatistical methods. As a result, we determine the exact position of the discontinuity line in the next seam. The paper also presents several algorithms for checking the deposit model made using the methods developed by the authors, including the analysis of outliers (in terms of elevation and inclination), testing the variability of the fault throw, checking the distance between adjacent seams, and verifying the position of the deposit in relation to the existing workings and boreholes. It should be noted that the key issue while building a deposit model is a checking of the model, removal of the assumptions and, obviously, incorrect data in order to obtain the highest possible accuracy.

Statistical data on occupational diseases registered by the Institute of Occupational Medicine in Łódź indicates a renewed increase in the number of pneumoconiosis in Poland in recent years, especially in the section of PKD (Polish Classification of Business Activities) – mining. Simultaneously, in 2018, because of the implementation of Directives of the European Parliament and the Council of the European Union, changes were introduced to Polish legislation in the field of protection of workers against the risk of exposure to carcinogens or mutagens related to the respirable fraction of crystalline silica formed during work. Considering this information, the members of the Department of Safety Engineering of the Silesian University of Technology attempted to assess the dust hazard and the frequency of occurrence of respiratory diseases among the employees of the preparation plant of mine X exposed to the harmful effects of industrial dust produced in the work process. The following methods were used as part of the research: individual dosimetry, infrared spectrometry, directional interview, diagnostic tests, and spirometry. The obtained results made it possible to identify workstations with the highest exposure to the harmful effects of industrial dust and to recognize the impact of this action in the form of pathological changes in the respiratory system in 18.4% of the miners surveyed.

The article presents results on the influence range of mining exploitation in a rock mass at the site of dog headings located in an area of intensive mining exploitation. The research is based on geodetic measurements of the subsidence of measurement line points located above the panel of a mined-out longwall. Studies were applied to assess the range of mining influence in a rock mass, which is important for the protection of dog headings against mining damage. If a range of mining influence comprises any protected workings, then the deformations caused by mining operations may result in the loss of their functionality and even in dangerous damage to them. The values of the parameters of the influence theory determined by geodetic measurements of subsidence can be used to determine the permissible length of longwall panels, ensuring the maintenance of the functionality of the protected dog headings and to optimize stress concentration zones in terms of the risk of rock mass tremors.

This article presents an economic analysis of the exploitation of the main mine drainage according to the condition of machines. The study is based on actual operating data obtained during the operation of an underground hard coal mine. Through the selection of state estimators, appropriate sensory systems, as well as a long-term economic approach, operating procedures were developed that allowed for the introduction of significant financial savings. Operating costs are reduced by lowering energy consumption and reducing the costs of current repairs and spare parts. In addition to the classic approach to monitoring the state of a machine, based on the observation of residual processes, a global coefficient, referred to as unit energy consumption, has been proposed. Thanks to this, the operation of the machine occurs not only on the basis of its current dynamic state, but also due to the control processes of the machine’s operation. Moreover, the article refers to the area related to water safety and the reliability of the pumping station.

Currently, the Polish power industry is mainly based on solid fuels, such as hard coal and lignite, and there is a problem with the management of significant amounts of combustion waste. One of the directions of recovery of these types of waste is underground hard coal mining operations, where the general problem of their management is the variability of physical and chemical properties resulting from the combustion of fuels of different parameters in power boilers with different exhaust gas cleaning solutions, mainly desulphurization methods. One of the solutions for energy production currently in use is the combustion of coal in fluidized bed boilers, in which the so-called dry desulfurization method is adopted. As a result of this process, a fine-fraction waste with the European code 10 01 82 is created, which is characterized by pozzolanic features, enabling its use wherever specific strength parameters are expected from the material. One such technology is the liquidation of underground workings based on the pouring of a hydro-mixture into the fenced-off space of the workings using a gravity-fed pipeline. The space to be filled is fenced off by closing it on both sides with dams, usually made of brick walls, located at an appropriate distance. It should be taken into account that the hydro-mixture will tend to slow the sedimentation of solid particles on the spreading path, and working may have a variable slope. The paper presents the results of laboratory tests of the physical and mechanical properties of hydro-mixtures made on the basis of selected energy waste from a fluidized bed boiler, along with a practical example of its application for the liquidation of underground workings.

The modern security environment is marked with significant changes and unpredictability. This is true both for natural threats caused most often by forces of nature and for threats to civilization such as technical disasters or failures. The fact that these threats may be synergistic not only complicates efforts that are mainly intended to mitigate them but also makes it difficult to determine their direct cause. The article presents a hypothetical model of the spread of dangerous substances released during a disaster involving a tanker carrying 20,000 kg of anhydrous ammonia by road, by rail, and by water in the territory of the Municipality of the City of Szczecin. A 2016 rail disaster involving two derailed tankers carrying ammonia is proof of the likelihood of such an event. Great amounts of dangerous substances are transported through Szczecin’s densely populated areas, most often to and from Zakłady Chemiczne Police S.A. (Police Chemical Plant), which causes a risk to the life and health of persons on the premises. The method of situation assessment in chemical, biological, and radiological contaminations (ATP 45 (Delta)) and the Promień IT system were used to forecast the hypothetical development of contamination. The results were compared with those of the ALOHA program. The author assumes that the conclusions from this paper will be used in the assessment of the likelihood of threat categories (KZ-3) and in the crisis response procedure (PRK-15), both included in the Municipal Crisis Management Plan.

To optimize the everyday functioning of a city, urban authorities can implement smart city tools and solutions. Mobility is a typical field associated with the concept of a smart city. It is interesting to take a closer look at the solutions applied through the information accessible on the official websites, while exploring, at the same time, the possibilities offered by new research tools. The main objective of this work is to establish the significance of the information and communication technologies (ICT) in the process of creating smart mobility in a smart city, based on the texts posted on official websites. Using the natural language processing (NLP) methods and tools offered by the CLARIN.EU infrastructure, we verified dominant connotations with the mobility in the cities recognized as smart. The cities sample is the extract from the existing smart city rankings. To fulfil our goal, we searched for an answer to the question: What information about ICT solutions is posted on the websites of the studied cities and in what thematic contexts are they used? We looked for the results of the smart city rankings, referring to the official websites of the selected cities (a random selection from a total of 174 cities). The results show that mobility forms a distinct topic in smart cities communication, covering various kinds of transport solutions and systems, with a strong focus on the project side of this activity. The results are the part of the research “The smart city 4.0 maturity model,” conducted at the Department of Marketing and Logistics UO.

Rising awareness of sustainable development challenges, along with the quest for optimization of the everyday functioning of the city, motivate many urban authorities to search for promising concepts and solutions. One of these is the smart city concept, which has gained governors of cities’ attention for little more than ten years. An object of research and development, it is still a distinctive feature for the cities that adopt this concept. City marketers use such distinction towards a large palette of beneficiaries of the city. At the same time, it deploys some traits suggesting synergies between the implementation of smart city solutions and sustainable development goals. The main objective of our work was to verify if the relationship between these aspects (smartness and sustainability of a transportation) in smart city rankings exists and, if that is true, what impact it has on marketing communication of the city comprised in such rankings. To fulfill this goal, we answered such research questions as: what place sustainability criteria in smart city rankings have occurred, how is the transport represented in these criteria, what use graded cities make of their presence in such competition, and which perspective dominates (if any) in daily marketing communication activities of the city. To provide such an analysis, we considered the criteria used to rank the cities to find the places that accorded to sustainable ones. We examined the marketing use of the results of such rankings, referring to the official websites and social media of selected cities (random selection from the total population of 174 cities comprised). The sources used to provide the data in natural language, and their analysis proceeded with methods and tools used in NLP (natural language processing), which are accessible through CLARIN.EU infrastructure. The results determine that cities can be classed into different groups, accordingly to their sustainability/smartness pending, and ability to use accorded ranks in marketing context.

This article analyzes the expectations of the management board and managerial staff as opposed to the expectations and concerns of regular employees of the company. Communication between the decision-making and executive groups is presented as one of the key elements determining the proper operation of the quality management system in the enterprise. In the practical part, the results of the research covering the management and regular employees were presented and compared. The research is aimed at diagnosing the quality of information flow in the enterprise based on the quality management system in the assessment of both surveyed groups, determining the perception of the importance and scale of participation in the proposed corrective actions among the surveyed groups of respondents, and diagnosing the level of informing rank-and-file employees about the goals and importance of conducting internal and external audits. The research also covered the role of lower-level employees in the effective functioning of the company’s quality management system. An attempt was made to analyze the degree of participation of regular employees in the functioning of the quality management system in the enterprise. The article ends with the conclusions and proposals for future research.

Hazard identification and occupational risk assessment, defined as the probability of occurrence of unfavorable work-related events, is one of the areas of activity for employers in relation to current legislation and standards. Using occupational risk assessment it is possible to design and use workstations properly, respecting workers’ health. This article presents an issue related to the use of workstations with laser equipment, which describes the nature of work of lasers and the specific impact of the laser beam on the material. The subject of the analysis is the workstations with a CO2 laser for cutting polymers and a workstation with a fiber laser for marking and engraving. For the above-mentioned workstations, using a designed checklist, the features of lasers are verified, hazards are identified, and occupational risk is estimated using the risk graph method. The estimated risk at selected workplaces with lasers clearly indicated that special attention should be paid not only to the device, and the negative impact of their laser beam on the human body, but also on the treated materials. The article also draws attention to protective measures, which should be applied at laser workstations to ensure the safety of employees.

This study aims to identify a model for building a resilient supply chain in a company testing engine oil samples. Unstructured face-to-face and structured remote interviews were used as the research methods. The proposed contextual research procedure allows for the elucidation of the content of the components of the final resilient supply chain model and may facilitate theory building on the basis of future multiple case studies. As a result of the research, it was found that at the level of the described chain, its strength and continuity of flow are based on the durability of relationships with suppliers, speed, trust, and information sharing, the role of which has been explained in relation to the nature of the supply chain. Due to the nature of the chain, building its resistance on the basis of agility, which is most often indicated in model approaches, has no justification in this case. It was also established that in this process, 4.0 technologies such as the internet of things (IoT), machine learning, artificial intelligence, and cloud technologies are more important for management at the level of the entire corporation than at the level of the tested chain. The analysis covered the supply chain embedded in the industry, which (according to the author’s knowledge) was not discussed in the context of logistics processes in world literature. Therefore, the results of the work undertaken are of great cognitive value.

Manufacturing, as one of the main pillars of a civilized lifestyle, will be strongly affected by sustainability issues, and it will play an important role in establishing a sustainable future. Within the area of sustainability issues, some specific issues are pointed out, such as the energy and labor intensity of manufacturing processes. The main aims of this paper are a systematic literature review and the evaluation of the energy and labor intensity of manufacturing processes in an industrial enterprise while proposing changes toward sustainable development. In the research, 163 scientific publications (77 related to China) were taken from the Web of Science (WoS) database based on selected keywords describing the studied phenomenon. The analyzed publications were divided into five areas (clusters). In terms of evaluating the energy and labor intensity of manufacturing processes, twelve production processes were selected, which were then grouped according to their most important areas of similarity (automation, ergonomics, and discomfort). The systematic literature review was carried out using the VOSviewer software, version 1.6.14. This article also uses the methodology of a case study with a simplified SWOT analysis based on interviews with employees and expert panels. The subject of the research is an industrial enterprise representing the steel manufacturing sector in Poland.