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  • Sokoła-Szewioła, Violetta; Poniewiera, Marian (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Ignac-Nowicka, Jolanta (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Barczak, Agnieszka (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Depczyński, Radosław (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Dembińska, Izabela (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Dear Readers, We are pleased to present you the next issue of our journal, Scientific Journals of the Maritime University of Szczecin. Fourteen articles are presented in this issue, the problems of which fall under the following subject areas: Civil Engineering and Transport, Material and Mechanical Engineering, Environmental Engineering, Mining and Power Engineering, Information and Communication Technology, Economics, Management and Quality Science, Sustainability Management. We are pleased that the manuscripts submitted to us cover a wide field of research, thus giving our readers the opportunity to analyze and give their opinion on a variety of research problems. In the Civil Engineering and Transport section, we present two studies. The first study investigated the effects of buoys and solid mass on mooring lines and the dynamic response of the floating platform. The results of the analysis show that increasing the number of buoys at constant volume contributes to a decrease in the amplitude of wave and tilt motion, while lifting motion increases slightly. On the other hand, adding a buoy and clump weight to the mooring line reduces the tension of the vibration amplitude. The second study characterizes the distribution chain of liquefied natural gas in Poland, paying particular attention to the possibilities of road transport. It has been noted that during transportation and storage, LNG vaporization, known as boil-off gas, is a significant problem leading to an increase in tank pressure. Hence, one solution to this problem is to compress it to high pressure, which produces compressed gaseous fuels. In the Material and Mechanical Engineering Section, we have six manuscripts. As the authors write in the first study, one of the primary hazards associated with the operation of marine and deep-sea vessels-particularly ship power plants-are fires and explosions, which cause accidents and incidents with an average frequency of up to every 60 days. The article discusses the explosion hazard status of the crankcase of main propulsion engines of various types of vessels. The evaluation was based on the results of statistical analysis of historical data from 1972–2018. Based on the analysis, it was generally shown that the risk of a crankcase explosion affects ships of all ages and that the number of serious incidents remains constant over the period studied. It is interesting to note that half of all incidents occurred on vessels younger than 15 years. The second article describes the prospects for ultrasonic cleaning of shell-and-tube heat exchangers used, among others, on ships. This is because the main problem of seawater heat exchangers is their clogging – as a result of the operation, over time a process of overgrowth begins (e.g., algae), leading to reduced efficiency. In order to obtain information about the distribution of ultrasonic power inside the reactor, the authors conducted a finite element simulation using a designed test reactor represented by a shell-and-tube heat exchanger with ultrasonic-assisted cleaning. The simulation results are presented in the article. The authors 6 Scientific Journals of the Maritime University of Szczecin 71 (143) of the next article in this section point out that concrete is currently the most widely used man-made composite material and is second only to water across the range of materials used. This paper presents the results of a study of the effect of partial replacement of Portland cement with fly ash on the strength parameters, frost resistance and carbonation of concrete in comparison with a reference concrete and concrete containing a conventional additive – silica fly ash. The results obtained confirmed the feasibility of producing plain concrete modified with fly ash from thermal treatment of sewage sludge, while demonstrating the compliance of concrete parameters with environmental requirements for the leaching of heavy metals. Concrete was also analyzed in the following article. It presents the effects of the addition of steel and propylene fibres on the mechanical properties of floor concretes, such as compressive and tensile strengths in the flexural test. It was shown that the amount of steel fibres dosed in the study, regardless of their shape, does not adversely affect the consistency and workability of the concrete mixture. On the other hand, the addition of polypropylene fibres has a significant impact on the properties of the concrete mix. In the introduction of the following article, the authors explain that a digital twin is a digital replica, a mathematical model of a given object, product, process, system or service. It enables the acquisition of a significant amount of data and can be used to obtain comprehensive knowledge about a given object, its behaviour and reactions. The authors analyzed the operation of a rotating bearing in a wind turbine structure using a digital twin model, and more specifically, analyzed the distribution of loads prevailing in the rotor blade bearings at wind turbine limit loads. The basic types of the most commonly used rim bearings for wind turbine applications are analyzed. In doing so, a methodology for building computational models of rim bearings using the finite element method was developed, as well as an original method of simulating rolling elements with rod elements (for rollers and super elements) for load-bearing balls was proposed. The subject of research in the last article of this section is stainless steels widely used in various automotive parts. Knowing that some of them are exposed to the external environment, the pitting corrosion resistance of two austenitic stainless steels was analyzed, i.e., AISI 304 and AISI 316L in road salt solutions of 5% wt. and 10% wt. Experimental results confirmed the lower pitting corrosion resistance of AISI 304 stainless steel in a 10% wt. road salt solution. We present one article in the Environmental Engineering, Mining and Power Engineering section. It notes that the biggest problem of creating a numerical model of a coal seam is the insertion of discontinuity lines: faults, seam connection lines, wedging, etc. Therefore, proprietary methods were developed to determine the spatial location of faults, implemented in Geolisp in CAD. A method is presented for calculating the spatial position of a fault based on existing contours reaching it from both sides, a method based on the assumption that the slope of the deck upstream and downstream of the fault is constant, a method based on making independent surfaces of the updip and downdip sides with kriging extrapolation, a method based on transferring the fault from the deck above it or the Carboniferous roof. It was assumed that the correct introduction of the fault course is important for the accuracy of forecasting the impact of mining operations on the rock mass and surface. Two studies make up the Information and Communication Technology section. The Automatic Identification System (AIS) device is mandatory on ships that comply with the International Convention for the Safety of Life at Sea (SOLAS), the first study reads. AIS is designed to monitor vessel traffic in order to improve shipping safety. In their study, the authors compare the execution speed of geospatial queries in the relational database engine PostgreSQL and the non-relational database engine MongoDB. Four AIS datasets, four test polygons with different numbers of vertices, and a reference point on the fairway were defined for the study. The tests were used to evaluate the execution of queries in the database, which shows the number of ships in a given area and the number of ships within a given distance from a defined point. Test results say that test queries are executed faster, and data stored in the database takes up less disk space in MongoDB compared to PostgreSQL. Justifying the need for the research, the authors say that faster geospatial analysis of AIS messages can improve navigation safety by detecting dangerous situations earlier. The second article in this section highlights the use of satellite tracking during an environmental disaster at sea and evaluates the feasibility of using remote sensing images captured by satellites using multispectral cameras and Synthetic Aperture Radar (SAR). The purpose of the analysis is to evaluate selected remote sensing methods for detecting and tracking marine debris. The research value of the analysis is determined by the fact that the study was conducted in real-time at the time of the incident. The Economics, Management and Quality Science section is filled with one article. The object of research inquiry in this case was the pallet. The purpose of the article was to present the issues of pallet pool players’ Zeszyty Naukowe Akademii Morskiej w Szczecinie 71 (143) 7 strategies and the organizational, operational and market challenges they face in such a way that they are better understood by all supply chain players. The author proposes adopting a value-added synergy perspective as an alternative, understood as different and complementary, rather than excluding opportunities for other approaches to supply chain value. The final section, Sustainability Management, begins with a study highlighting the impact of increasing container throughput in the northern Adriatic ports on air quality. A comparative analysis of air quality consisting of certain environmental parameters taken from selected measuring stations near the container terminals of the northern Adriatic ports of Rijeka, Trieste, Koper and Venice was carried out. The study showed that the increase in container throughput in the ports of the northern Adriatic did not affect the deterioration of air quality in the urban areas of the various port cities. Air quality values in the ports of the northern Adriatic are well below the limits set by the EU Directive in the area of air quality (2008/50), i.e., they do not negatively affect the health of the residents of the analyzed cities. The subject of the next article was the relationship between the seaport and the city in the aspect of sustainable development, particularly in environmental terms. The consideration was based on the thesis that the introduction of the concept of sustainable development in the port can stimulate the creation of green cities. A case study of the sustainable development of the Twin Port of Bremen was used in the deliberations. Port development has been shown to stimulate GDP growth, increase employment, develop urban infrastructure and contribute to the enrichment of port cities. And the development of ports on an environmental basis also becomes a stimulus for green city development. I hope that the presented studies will meet with wide interest, and at the same time inspire various interdisciplinary thoughts, discussions and research. dr hab. Izabela Dembińska, Associate Professor Editor-In-Chief Szczecin, 30.09.2022
  • Sokoła-Szewioła, Violetta; Poniewiera, Marian (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The largest problem that we encounter when creating a numerical model of a hard coal deposit is to insert discontinuity lines representing faults, seams junction lines, wedging, etc. The faults introduced on the map of the seam are mostly flat polylines, while we do not know the altitude ordinate. In order to determine the spatial position of the faults, authoring methods have been developed and implemented in the Geolisp software and in the CAD system. This article presents the method based on calculating the spatial position of the fault with respect to the existing contours, which arrive at it from both sides, the method based on the assumption that the inclination of the seam in front of and behind the fault is constant, the procedure involving the performing of independent surfaces of the upthrow and downthrow side with extrapolation by the Kriging method, and the procedure requiring the transfer of the fault from the above-lying seam or a Carboniferous roof. The solutions given in the article are successfully used in most mines in Poland. The correct introduction of the fault course is important for the accuracy of forecasting the impact of the mining operations on the rock mass and the surface area.
  • Ciecińska, Barbara; Oleksiak, Beata; Furtak, Julia (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Jedliński, Mariusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    A flat wooden pallet, being a simple logistics carrier in terms of its structure, can nonetheless be treated as a highly specialized logistical and marketing object applied in complex supply chains. Rigorous measures taken to standardize pallets are predominantly aimed at ensuring the highest possible safety level for the transported products and people handling the freight units during the complex logistical processes that involve pallets along supply chains. The goal of this article was to increase understanding of the operating strategies employed by entities using pallet pools, as well as the organizational, operational, and market challenges faced by them. It was hoped to achieve this goal via both theoretical and empirical studies. To this end, the research study applied theoretical synthesis and empirical evidence derived from primary research based on the industrial, transport, forwarding, and logistics markets. At the same time, the theoretical context was based on the literature on the subject, related to wooden pallet issues and their special role in logistical processes. Challenges connected with decisions made to enable effective and efficient management of pallet pools were addressed at legal and regulatory, as well as organizational and operational, levels. Diverse courses of action identified in several stakeholder groups were reflected in the adopted philosophy of managing the main feeding streams of pallet pools. Though limited to just the Polish market, the research study was sufficiently representative due to the strategic share of the European and global market of standard flat wooden pallets. The author proposes taking a perspective of value-added synergy as an alternative (to be understood as different and complementary rather than excluding possibilities) to other ways of approaching the value of supply chains. The undertaken considerations may contribute to increasing the awareness of the importance of taking a pallet, so common from the technical and technological point of view, as a value-added carrier in scientific considerations, due to its paradoxically low individual economic vulnerability.
  • Kauf, Sabina; Pisz, Iwona (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Sroka, Mariusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Wiaterek, Daniel; Chybowski, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    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.
  • Zatkalíková, Viera; Markovičová, Lenka; Valčuhova, Daniela (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Stainless steels are widely used for various automotive components. Some of them (e.g., parts of the exhaust system) are exposed to the external environment. In winter conditions, they are affected by chloride containing road salt solutions, which can lead to the local corrosion of these stainless steel parts. The presented paper is focused on the pitting corrosion resistance of two austenitic stainless steels (AISI 304 and AISI 316L) in 5 wt% and 10 wt% road salt solutions. The evaluation and comparison are based on the potentiodynamic polarization test method carried out at the temperature of 20 ± 2°C. The pitting potentials were determined from the polarization curves. Local corrosion damage of exposed surfaces caused by potentiodynamic polarization in the used solutions was observed by optical microscope. Experimental results confirmed a worse pitting corrosion resistance case, especially for AISI 304 stainless steel in 10 wt% road salt solution.
  • Krynke, Marek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    A digital twin is a digital replica, a mathematical model of a given object, product, process, system, or service. A digital twin enables the attainment of a significant amount of data and it can be used to gain comprehensive knowledge about a given object, its behaviors, and reactions. The constant ability to monitor the product and its reactions contribute to its improvement and the exclusion of errors, as well as its optimization, which in turn allows for a more perfect product. This article presents a model of a digital twin for the analysis of the operation of a slewing bearing in the structure of a wind turbine. The quality of the bearing is directly related to the quality of the materials from which they were made, the process of thermo-chemical treatment, and the accuracy of all its elements, as well as its proper assembly. The bearings are characterized by very narrow tolerances. Errors in the shape of cylindricity cause distortion of the bearing raceway, stress accumulation, and jamming of rolling parts. This leads to rapid bearing wear as a result. The condition for the approval of bearings for sale is the successful passing of all tests, both geometric and strength. This is to develop quality standards that bearing suppliers must meet. The article presents an analysis of the load distribution that prevail in rotor blade bearings at the limit loads of a wind turbine. The basic types of the most commonly used coronary bearings for wind turbine applications were considered. A methodology for constructing computational models of slewing bearings, using the finite element method, was developed. An original way of simulating rolling parts with rod elements – for rollers and superelements – for the support balls was proposed. A numerical FEM model of a slewing bearing with a wind turbine rotor hub is presented. The calculations accounted for the susceptibility of the bearing rings and hub, as well as the stiffness of the mounting screws. Areas of bearing raceways, where rolling parts achieve the greatest loads, have been identified. Demonstrated by diagrams are the deformations of the rotor hub seats and bearing rings.
  • Helbrych, Paweł (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents the effect of the addition of steel and propylene fibers on the mechanical properties of floor concretes (compressive and tensile strengths in the bending test). The polypropylene fibers used in the tests (fibrillated and single fibers) are dosed in the amount of 0.5 kg/m3 to 2 kg/m3, and the straight and hooked steel is dosed from 10 kg/m3 to 25 kg/m3 . It is shown that, after 28 days of maturation, the highest compressive strength is achieved by concretes containing the addition of 25 kg/m3 of hook-like steel fiber. In addition, the influence of the fiber content on the consistency of the concrete mix and workability is investigated. It was shown that the amount of steel fibers dosed in the tests, regardless of their shape, did not adversely affect the consistency and workability of the concrete mix. On the other hand, the addition of polypropylene fibers has a significant impact on the characteristics of the concrete mix. The addition of 2 kg/m3 of polypropylene fibers caused the change of consistency from S4 to S1/S2 and worsened the workability of the mixture. All of the tested series of the concrete are created using the same technology. The concrete production technology reflects the concrete production technology for flooring concretes.
  • Bohdan, Adriana (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Seaports and cities are internally linked, and the port can have a strong influence on the city, especially in the environmental aspect. Port authorities around the world are striving for greener forms of port management to adapt to state policy and to increase their economic and environmental competitiveness. The introduction of the concept of sustainable development in the port can stimulate the creation of green cities. This paper uses a case study to analyze the sustainable development in the Twin Port of Bremen. The aim is to distinguish the green port’s impacts that can stimulate the development of the green city concept. It is shown that the port development stimulates GDP growth, increases employment, urban infrastructure development, and the overall enrichment of port cities. Using the presented analysis of the green port, the most important affecting factors are proposed.

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