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This paper examines the factors affecting the performance of VTS operators. A general review of the human factor as a determinant of navigational safety is presented. The elementary nature of the system and its structure are defined, and the ability of a VTS operator to perform planned tasks within a specified timeframe and in a specific manner is analyzed. A reliability assessment scheme is proposed,...
Charge air cooling is essential for the efficient operation of marine diesel engines. This work presents the results of research on the characteristics of long-range heat transfer surfaces for marine diesel engines. Elliptical and flat-oval tubes were considered. This study was carried out using mathematical models that consisted of the equations for energy conservation, motion, continuity, and state...
The hydrodynamic performance of trimaran hulls has been previously investigated for optimum performance in calm water, but there is still a limited understanding of its motion response; therefore, a CFD-based numerical approach was developed and applied on a trimaran hull in the presence of regular and irregular waves. To validate the CFD method, a comparison was conducted using both experimental...
In Europe, at the end of the 20th century, the growth of marinas followed the rapid development of recreational marine activities. This trend has now slowed and today the creation of new marinas or the extension of existing marinas is less common, mainly due to the enforcement of protective environmental regulations. As the port sector is facing some major sustainability challenges, like tackling...
Presented are regulations concerning the operation of passenger ships (with particular emphasis on Polish ferries) designed to increase maritime safety the SOLAS Convention, established in 1974 and codified in 2002, codifies these regulations, and the International Maritime Organization mandates additional regulations, created in response to a rapidly increasing number of maritime disasters. The analyses...
In this paper, a special configuration for the huge multipurpose machine tool of “travelling column” type was investigated by the finite element analysis. Internal degrees of freedom of a bulky system consisting of the ram, stock, column, sledge and bed, were implemented by the hydrostatic guides. A simulation of coupling two assembled columns into the portal structure was completed. The results of...
This article presents an analysis of internal forces and roll motion during a nodule loading simulation for a ship at sea. The study carried out a full assessment of ship behavior during loading, which took into account wave height and period occurrence around the Clarion–Clipperton Zone by the use of an operational efficiency index. One of the aims was to verify whether waves have an influence on...
The results of finite element analysis of large machined rotor fastened into heavy precise lathe are reported. Many design changes are simulated to improve the dynamic rigidity of the machining. Three radial eigenmodes detrimental to the accuracy were revealed: rotor-stock bending at 17.7 Hz (“half-wave”), rotor-lathe bending at 36.1 Hz (“full-wave”), and “support rocking” at 68.1 Hz. The frequency...
This article discusses issues related to the concept of corporate social responsibility (CSR) of Polish universities. The first part of the article presents the essence of CSR, and the next part focuses on the degree of involvement of universities in Poland in CSR activities. Afterwards, the CSR activities were grouped based on conceptual areas in accordance with the ISO 26000 standard. Moreover,...
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...
Transport is integral to every city, having a crucial impact on its functioning and development. As road infrastructure does not up to keep up to speed with the constantly growing numbers of vehicles on roads, new solutions are required. Fast urban railway systems are a solution that can reduce transport congestion, with environmental protection issues also taken into account. Following these reasons,...
A holistic approach and stakeholder consultation are necessary before implementing a particular city logistics measure. The need to implement sustainable urban logistics solutions is particularly important in seaports located in cities. Such cities, particularly Gdynia, have a high intensity of cargo flows resulting from transport connected with their port facilities. The purpose of this article was...
The COVID-19 pandemic and the strict anti-epidemic measures introduced by various countries have accelerated the transformation of tourism around the world. The industry has lost hundreds of billions of dollars and millions of jobs. At the same time, digital startups have entered the market, and new opportunities for individual tours and formats of international cooperation have appeared. Trends for...
Environmental pollution is a growing concern for many organizations, commissions, state governments, and companies. The use of fossil fuels in transportation contributes significantly to increased emissions of harmful sulfur oxides (SOx) and nitrogen oxides (NOx). Maritime transport, as one of the largest emitters of such harmful compounds, has encountered many emission restrictions and legal limitations...
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...
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...
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...
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...
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...
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...
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