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  • Piotr, Korlak (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Existing and future regulations on ship energy efficiency and methods for their improvement are presented in this work. The design and operational features of gas-fuelled low-speed main engines, liquefied natural gas (LNG) regasification conditions, and amount of waste cold are compared. Using a simple linear regression model based on the least squares method, formulae were developed to predict the amount of waste cold as a function of the brake power of gas-fuelled low-speed main engines operating under ISO ambient conditions in Tier III-compliant mode. A sufficiently accurate prediction of the waste cold amount at the initial design stage is feasible due to the formulae developed as part of this work.
  • Majda, Jurić; Čedomir, Dundović; Tina, Perić; Gorana, Jelić Mrčelić (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    shore terminal, or Floating Storage Regasification Unit – FSRU) was presented based on holistic evaluation of the impacts of potential LNG terminal. The first step was to divide the entire observed area of the Adriatic Sea of the Republic of Croatia into smaller areas by using the Geographic Information System (GIS), and to select areas where installation of LNG terminal is technically feasible based on the pre-elimination criteria. Potential LNG terminal areas were selected taking into account all pre-elimination criteria and 14 areas were selected by using pre-elimination criteria in GIS smart charts tool that enables analyses of spatial data. The second step was based on elimination criteria analyses of 14 areas selected in the first step by pre-elimination criteria analyses. Six potential LNG terminal micro-locations were singled out based on defined elimination criteria. The third step included experts’ evaluation of 38 specific sub-criteria classified into five distinctive groups of sub-criteria: economic group (11 sub-criteria), ecological group (13 sub-criteria), safety group (4 sub-criteria), traffic connection group (6 sub-criteria) and gas needs (4 sub-criteria) for six areas singled out in previous step. The fourth step was to make multi-criterial expert analysis of the six locations selected in the previous step (for onshore terminals, offshore terminals and FSRU) for three different scenarios analysis by the PROMETHEE (Preference Ranking Organization Method of Enrichment Evaluation) method. In every scenario, one group of sub-criteria was selected as the most important according to its cumulative relationship with other groups of criteria (scenario 1 – economic group of the criteria, scenario 2 – ecological group of the criteria, scenario 3 – safety) and different importance was given to every of the sub-criteria (the sub-criteria weight). The methodology presented in this paper can also be used in decision making process for other marine and coastal activities where incorporating an ecosystem approach is an important issue taking into account safety and project costs, but the selection of pre-elimination criteria, elimination criteria and the sub-criteria should be carefully adjusted to the other situation or activities.
  • Paweł, Zalewski; Katarzyna, Posacka (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The International Maritime Organization (IMO) introduces, adopts, and implements new instruments, such as conventions, resolutions, and guidelines, to prevent and minimize the number and severity of accidents involving ships at sea. The results of international maritime safety requirements introduced in recent years are presented in this paper. The impact of these regulations on ship safety improvement in European marine waters was determined via an analysis of accidents over a seven-year period of 2014–2020. The analysis was based on the classification of accidents by their severity, by the type of ship involved, and by the identified causes or contributing factors. Evident, still existing “weak points” of maritime safety monitoring are emphasized, such as low reporting of incidents and superficial identification of contributing factors. It is worth noting that the technological development of marine electronic systems introduced both positive effects and novel threats to the safety of navigation. An example is an uncritical overreliance on technology and information provided via electronic means and sensors. In this context the usage of integrated, digitized bridge systems in contemporary maritime vessels and future remote control systems was stressed.
  • Zbigniew, Szozda; Piotr, Nowakowski (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Ships' stability criterion due to turning is not up-to-date and requires amendments. Redesigning the criterion should be based on scientific research, but there is a lack of accurate procedures and formulas enabling the calculation of the heeling moment caused by centrifugal forces as a function of time. Measurements of a ships’ heel caused by turning on a model-scale or full-scale may provide a basis for such an analysis. This paper creates such a procedure, including appropriate formulas, leading to the extraction of the heeling moment caused by centrifugal force from other heeling moments acting on a ship during turning. One model-scale experiment is described in detail, and the results of the calculations are presented. The paper concludes that it is possible to extract this moment as a function of time and presents an example of such a calculation.
  • Dariusz, Milewski (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The problem presented in this article concerns the impact of demand characteristics for consumer goods on the profitability of purchasing strategy, including the choice of both the source of supply and transport technology (deliveries in containers by sea, rail, air, and road transport). To assess the profitability of applying a specific strategy, the author developed a model to conduct simulations using the Monte Carlo approach for two demand distributions (Gaussian and Gamma), various sales fluctuations, and changes in demand during the delivery time. Calculations were carried out considering the costs of transport, storage, capital costs related to maintaining stocks, and costs of lost sales. The simulation results show that the greater the fluctuations and the lower the predictability of the demand, the greater the profitability of deliveries using air transport and local deliveries. However, concrete decisions depend on knowledge of the consequences of making these decisions and whether appropriate cost accounting is used in enterprises. The results of the calculations also indicate that the strategy of outsourcing production in low-cost countries will, in many cases, become unprofitable if production costs in these countries increase even slightly.
  • Mariusz, Jedliński (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The progressive unpredictability of socio-economic or biological changes (e.g. the SARS-CoV-2/COVID 19 pandemic), the multi-directional nature of their impact, the variability of intensity, and the uncertainty in estimating potential effects hinders the stable and planned operation of modern supply chains. This irreversible situation proves the high unreliability of existing traditional measuring instruments of classical economics and the methods used so far in the field of management and quality sciences. This article aims to present an exemplary set of expectations towards contemporary supply chains that are particularly relevant to the emerging market challenges in the form of mega-trends of threats and conditions, also those particularly emphasized during the SARS-CoV-2/COVID-19 pandemic. It is primarily a pandemic (taken as a critical exogenous factor) resulting in severe “disorders” in supply chains. The actual level of supply chain resilience depends on its inherent characteristics and is termed “vulnerabilities”, while an active supply chain response to emerging “disorders” is treated as its “resilience”. For these reasons, the author proposes a holistic view of the nature of the supply chain system and its processes. The proposed approach, based on the method of interpretative (qualitative) research enriched with the idiographic nomothetic approach, is treated as a creative alternative that does not exclude other possibilities of perception of the supply chain, but, in its intellectual diversity, complements other methods of understanding its system, processes, and logistics management. Such an approach with a dominant hypothetical-inductive The progressive unpredictability of socio-economic or biological changes (e.g. the SARS-CoV-2/COVID 19 pandemic), the multi-directional nature of their impact, the variability of intensity, and the uncertainty in estimating potential effects hinders the stable and planned operation of modern supply chains. This irreversible situation proves the high unreliability of existing traditional measuring instruments of classical economics and the methods used so far in the field of management and quality sciences. This article aims to present an exemplary set of expectations towards contemporary supply chains that are particularly relevant to the emerging market challenges in the form of mega-trends of threats and conditions, also those particularly emphasized during the SARS-CoV-2/COVID-19 pandemic. It is primarily a pandemic (taken as a critical exogenous factor) resulting in severe “disorders” in supply chains. The actual level of supply chain resilience depends on its inherent characteristics and is termed “vulnerabilities”, while an active supply chain response to emerging “disorders” is treated as its “resilience”. For these reasons, the author proposes a holistic view of the nature of the supply chain system and its processes. The proposed approach, based on the method of interpretative (qualitative) research enriched with the idiographic nomothetic approach, is treated as a creative alternative that does not exclude other possibilities of perception of the supply chain, but, in its intellectual diversity, complements other methods of understanding its system, processes, and logistics management. Such an approach with a dominant hypothetical-inductive character allows for creating a platform for broader scientific discussions, positioning itself in the sphere of simplifying reality or creating a theoretical construct for the possibility of formulating the foundations of the preliminary theory. These considerations lead to the conclusion that such an attempt at a new, broader perspective, both at the emerging threats and vulnerability, is related to the level of risk, demonstrating that the Supply Chain Critical Functionality is a consequence of many different factors, including time, costs, and delays in deliveries. Such a view allows for a more comprehensive systematization of the epistemological layer in the area of directional perception and application of logistics, showing many similarities but also significant differences with phenomena that are characteristic of other areas of logistics application and the perception of the conditions for the functioning of modern supply chains. character allows for creating a platform for broader scientific discussions, positioning itself in the sphere of simplifying reality or creating a theoretical construct for the possibility of formulating the foundations of the preliminary theory. These considerations lead to the conclusion that such an attempt at a new, broader perspective, both at the emerging threats and vulnerability, is related to the level of risk, demonstrating that the Supply Chain Critical Functionality is a consequence of many different factors, including time, costs, and delays in deliveries. Such a view allows for a more comprehensive systematization of the epistemological layer in the area of directional perception and application of logistics, showing many similarities but also significant differences with phenomena that are characteristic of other areas of logistics application and the perception of the conditions for the functioning of modern supply chains.
  • Katarzyna, Bobkowska; Izabela, Bodus-Olkowska (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Artificial neural networks (ANN) are the most commonly used algorithms for image classification problems. An image classifier takes an image or video as input and classifies it into one of the possible categories that it was trained to identify. They are applied in various areas such as security, defense, healthcare, biology, forensics, communication, etc. There is no need to create one’s own ANN because there are several pre-trained networks already available. The aim of the SHREC projects (automatic ship recognition and identification) is to classify and identify the vessels based on images obtained from closed-circuit television (CCTV) cameras. For this purpose, a dataset of vessel images was collected during 2018, 2019, and 2020 video measurement campaigns. The authors of this article used three pre-trained neural networks, GoogLeNet, AlexNet, and SqeezeNet, to examine the classification possibility and assess its quality. About 8000 vessel images were used, which were categorized into seven categories: barge, special-purpose service ships, motor yachts with a motorboat, passenger ships, sailing yachts, kayaks, and others. A comparison of the results using neural networks to classify floating inland units is presented.
  • Staude, Marek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Good quality in composite castings can be confirmed primarily by their user. The producer is obliged to create a good product that meets the user’s needs that should undergo quality control. Omission of technological procedures and improper quality control may result in various defects like porosity. This paper presents the characteristics of the casting defect, namely porosity, with a particular focus on porosity in suspension and saturated metal composites. This defect is different, specific to composite castings, making its identification very difficult. The aim of the study is to detect and describe porosity in composites with the use of microscopic and submicroscopic examinations. The assessment of the porosity of the microstructure of composite castings allowed for the formulation of the following conclusions: in addition to the porosity that occurs in castings of classic materials (cast steel, cast iron, and non-ferrous metal alloys), metal composites also distinguish between primary and secondary agglomerates, leaving the reinforcement space not filled, occluded bubbles, and separated gas bubbles.
  • Ghassemi, Mohammad A.; Ghadimi, Parviz; Sajedi, Sayyed Mahdi (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper examines the effect of the stern wedge length and height on the drag and trim of a chine-planing hull in calm water. To this end, fluid flow was simulated by Star-CCM+ software by applying an overset mesh and k-ε turbulent model. The finite volume method was used to discretize the fluid domain, and the fluid volume was utilized to capture the generated free surface. The considered model is a prismatic planing hull with a deadrise angle of 24°, a mass of 86 kg, a length (L) of 2.64 m, and a beam (B) of 0.55 m. For validation, the numerical results of drag and trim were compared against experimental data, which displayed good compliance. Subsequently, the hydrodynamic performance of the planing hull was investigated, and the wedge effect was assessed. The stern wedge was located at the bottom and near the aft perpendicular to the hull to facilitate a moderate distribution. Various wedge lengths of 0.2B, 0.5B, and B at two different heights of 5 mm and 10 mm were examined to assess the hydrodynamic performance of the hull at various speeds. The trim angle, resistance, water surface elevation, porpoising, roster tail, and the stern and bow were computed and analyzed. Based on the numerical results, it was concluded that when the wedge length increased, the drag and trim were reduced. It was also concluded that the best wedge for a vessel with desirable wake generation is one with a length of 0.2B and a height of 5 mm.
  • Smolska, Małgorzata (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Team coaching is currently used as a tool to help businesses cope with the process of managing team maturity. This article aims to present a team development process based on the High Performance Team Coaching Model. In the first part of the article, the theoretical essence of team coaching and the specificity of the team coaching process is characterized, together with detailing specific tools at each stage. In the second part of the article, the author describes the implementation process of the High Performance Team Coaching Model in business practice. The main research methods used in the article include literature studies and a case study based on the author’s observations and experience working as a coach/trainer in a project team.
  • Bošnjak, Rino; Bukljaš, Mihaela; Medić, Dario; Vukša, Srđan (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This study discusses the marine accident involving the Cosco Busan, the container ship that hit the base of the Delta Tower of the San Francisco-Oakland Bay Bridge in November 2007. An analysis of the elements resulting in the accident and its consequences has been carried out, followed by an analysis of the navigational risk using mathematical and tabular values. Mathematical values refer to the navigational risk in a specific sailing area, while tabular values refer to the navigational risk using a risk assessment. The main goal of this research was to identify and propose new measures that are correlated with a risk assessment. These measures should be applied in areas where an accident takes place so that future marine accidents can be reduced.
  • Agata, Krystosik-Gromadzińska (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Drones are entering the maritime sector and have successfully increased safety and security. They can effectively replace humans, and where life and health are at risk during operations such as tank or hull inspections, they can be used in a fully remote capacity. They are used to transport spare parts, documents, medicine, etc. between land and ships at sea or on the roadstead, which may increase safety during the COVID-19 pandemic. Drones can control traffic and the emission of pollutants from ships, detect pirates, monitor areas, and support operations. They are used in search and rescue missions and also provide modern technologies like 5G and others. Drones are reliable and effective, and their use minimizes costs and reduces time. This paper presents a current review of the state of knowledge on the use of drones in the maritime sector. It takes into consideration the opportunities of their utilisation and presents possibilities and examples of successful drone exploitation by various entities such as classification societies, shipyards, search and rescue (SAR) missions, and others. The benefits and limitations and a roadmap for drones in shipping are also analysed. An application forecast for the Polish maritime sector in the West Pomeranian and Pomeranian Regions is also delivered in the paper. Desk research methodology was used to review the literature to identify the set goals by analysing literature reports, articles, and materials published by beneficiaries using drones successfully, as well as inquiries and market offers.
  • Małgorzata, Bielenia (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The main objective of this article was to provide an overview of the polyurethane industry and waste treatment methods to identify the best method for polyurethane (PUR) reprocessing (recycling). To understand the need for recycling, existing knowledge will be referenced. Many literature studies discuss the role of recyclates in the polyurethane industry. According to these, the best available options to recapture value, for example, from raw materials, are polyurethane recycling and energy recovery. The research material was created via the glycolysis of polyurethane foam scrap. The experiments in this work include the glycolysis of polyurethane foam with a complex discussion of materials (polyurethane foam, glycols, catalysts, and properties of the obtained recyclate). Based on the research, analyses, and tests carried out related to glycolysis, the most appropriate conditions to recover polyols from scrap were the following reaction conditions: temperature 170–190°C; pH – basic; and atmosphere (air), which was the same for all samples. A total of 14 samples were tested. Two samples GL:12 [6:1] and GL 13 [8:1] were futher investigated. The numbers presented in brackets [6:1] mean that a ratio of 180 g of polyurethane foam and 30 g 1-3-propyleneglycol was used. The outstanding properties of glycolysate samples called GL:12 [6:1] and GL 13 [8:1] were achieved thanks to the ranges of the basic parameters (dosage time, time after dosage). The sample GL:12 [6:1] – dosage time 20 min and time after dosage 15 min and the GL 13 [8:1] sample – dosage time 22 min and time after dosage 15 min. The apparatus used for glycolysis included: reactor +heater, stirrer, feeder, reflux condenser, thermocouple, and temperature regulator. By analyzing the obtained results, it can be concluded that the most promising polyurethane waste management process is glycolysis.
  • Dembińska, Izabela (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Dear Readers, This is the second 2021 issue of our journal (No. 66). We are slowly seeing the world normalize after the COVID-19 pandemic, and we look forward to a complete return to our usual routines and to meeting again at conferences, seminars and research internships. Let us all hope that this will come true soon. Research results and author opinions are presented across seven articles in this issue, which are summarized in three thematic groups: Civil Engineering and Transport, Mechanical Engineering and Economics, Management and Quality Science.
  • Açik, Abdullah (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Many factors affect ship values, but the most important is freight rates. This effect is more dynamic, especially in the dry bulk market, which has characteristics close to a perfectly competitive market. The literature does not provide a complete answer about whether the effects of freight on ship values differ by ship type and age in the market; therefore, this study examined the effect of changes in the freight rates of the main ship types used in the dry bulk market on their values in different age groups. The ship types included in the study are Capesize, Panamax, and Handymax vessels, while the age groups are newbuilds, 5-year-old, and 10-year-old ships. Individual regression models were established and analyses were applied for each category. According to the obtained results, smaller vessels were more affected by changes in freight rates, and the effect of changes in freight rate increased with the age of the ship. Also, the price volatility of smaller ships was lower, while it was higher for older ships. It is hoped that these results may provide comparative results by ship type and guide industry stakeholders in reducing risks.

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