Search results for: ships,%20waves,%20white%20noise,%20damping,%20density,%20hull,%20seas,%20significant%20wave%20heights,%20testing,%20wave%20frequency - Bridge of Knowledge

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Search results for: ships,%20waves,%20white%20noise,%20damping,%20density,%20hull,%20seas,%20significant%20wave%20heights,%20testing,%20wave%20frequency

Search results for: ships,%20waves,%20white%20noise,%20damping,%20density,%20hull,%20seas,%20significant%20wave%20heights,%20testing,%20wave%20frequency

  • TEST METHOD FOR DETERMINING THE CHEMICAL EMISSIONS OF A MARINE DIESEL ENGINE EXHAUST IN OPERATION

    Publication

    The article briefly describes the problem of air pollution caused by sea-going ships and the resulting restrictions on the emission of toxic and harmful chemical compounds in the exhaust of marine engines, introduced by the International Maritime Organization (IMO) under the International Convention for the Prevention of Sea Pollution from Ships (MARPOL 73/78). Such emissions provide a significant metrological problem, not only...

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  • M2M communications system proposal for maritime applications

    This article describes the proposal to use the M2M communication to enhance the safety of people, ships and other marine infrastructure, in broadly defined marine systems. In addition, there are numerous examples of planned solutions to be implemented in the near future as well as new services. The proposal for M2M communication system architecture is described below. In addition, the use of the STRUGA system radio interface as...

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  • On ship roll resonance frequency

    Publication

    - OCEAN ENGINEERING - Year 2016

    The paper deals with the problem of modeling of rolling motion under a variety of excitation parameters. Special emphasis is put on the analysis and prediction of the frequency of the resonant mode of rolling, since it is often an essential issue in terms of motion of a ship related to her safety against capsizing or excessive amplitudes of roll. The research is performed for both free rolling and excited rolling and it is based...

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  • On reliability assessment of ship machinery system in different autonomy degree; A Bayesian-based approach

    Publication
    • A. BahooToroody
    • M. M. Abaei
    • O. Valdez Banda
    • J. Montewka
    • P. Kujala

    - OCEAN ENGINEERING - Year 2022

    Analyzing the reliability of autonomous ships has recently attracted attention mainly due to epistemic uncertainty (lack of knowledge) integrated with automatic operations in the maritime sector. The advent of new random failures with unrecognized failure patterns in autonomous ship operations requires a comprehensive reliability assessment specifically aiming at estimating the time in which the ship can be trusted to be left unattended....

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  • Multidipoles model of ship's magnetic field

    Ships made of ferromagnetic metals interfere with Earth's magnetic field in their surrounding. The disturbance of the magnetic field makes possible localization and even identification of the ship, which could determine a threat to the ship. The measurement of the magnetic field around the ship enables to determine its magnetic signature. The paper presents a multidipoles model of the ship magnetic field, which allows to determine...

  • Model of ship's magnetic signature

    Ships made of ferromagnetic metals interfere with Earth's magnetic field in their surrounding. The disturbance of the magnetic field makes possible localization and even identification of the ship, which could determine a threat to the ship. The measurement of the magnetic field around the ship enables to determine its magnetic signature. The paper presents a multidipoles model of the ship magnetic field, which allows to determine...

  • Multidipoles model of ship's magnetic field

    Publication

    Ships made of ferromagnetic metals interfere with Earth's magnetic field in their surrounding. The disturbance of the magnetic field makes possible localization and even identification of the ship, which could determine a threat to the ship. The measurement of the magnetic field around the ship enables to determine its magnetic signature. The paper presents a multidipoles model of the ship magnetic field, which allows to determine...

  • Ship domain applied to determining distances for collision avoidance manoeuvres in give-way situations

    Ship domain is often used in marine navigation and marine traffic engineering as a safety condition. The basic idea behind those applications is that an encounter of two or more ships can be considered safe if neither of ship domains is intruded by other ships. Research utilising this approach has been documented in numerous works, including publications on optimising collision avoidance manoeuvres performed to fulfil domain-based...

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  • Orientation-aware ship detection via a rotation feature decoupling supported deep learning approach

    Publication

    - ENGINEERING APPLICATIONS OF ARTIFICIAL INTELLIGENCE - Year 2023

    Ship imaging position plays an important role in visual navigation, and thus significant focuses have been paid to accurately extract ship imaging positions in maritime videos. Previous studies are mainly conducted in the horizontal ship detection manner from maritime image sequences. This can lead to unsatisfied ship detection performance due to that some background pixels maybe wrongly identified as ship contours. To address...

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  • Collision Risk-Informed Weather Routing for Sailboats

    Selected COLREG rules, good seamanship and sheer common sense indicate that it is in a sailboat's interest to follow collision-free routes without relying on large power-driven ships to give way. Until now, however, no method has integrated a sailboat's weather routing with collision risk monitoring and collision avoidance. Therefore, a new deterministic approach to combine the above features within one method is introduced here....

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  • Selection of an artificial pre-training neural network for the classification of inland vessels based on their images

    Publication

    - Zeszyty Naukowe Akademii Morskiej w Szczecinie - Year 2021

    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...

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  • An Integrated Approach to an Assessment of Bottlenecks for Navigation on Riverine Waterways

    Publication
    • M. Schoeneich
    • M. Habel
    • D. Szatten
    • D. Absalon
    • J. Montewka

    - Water - Year 2023

    Water transport, both sea and inland, is the cheapest, least invasive, and safest option for non-standard loads; hence, it is important to increase the percentage share of inland waterway transport on the rivers of Central and Eastern Europe. Transporting cargo is particularly difficult on shallow waterways because rivers overloaded with sediment determine the vertical parameters on inland waterways. A ship’s safe manoeuvrability...

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  • Lithuania inland waterways and its prospects

    Publication
    • V. Paulauskas
    • P. PLAčIENE
    • R. BARZDžIUKAS
    • A. Maniachin
    • D. Paulauskas
    • M. Wójcik

    - Year 2007

    Inland waterways have some traditions in Lithuania and in neighbor Countries, but during last 50 years other modes of transport move out inland waterway transport from real economical activity. In the same time inland waterways is the main green and sustainable transport system. In this article are presented analysis situation, methodology for the ships optimal using in inland waterways, forecasting of the possible cargo and passenger...

  • Evolutionary Sets of Safe Ship Trajectories: the Method's Development and Selected Reaserch Results

    The Evolutionary Sets of Safe Ship Trajectories is a method solving ship encounter situations. The method combines evolutionary approach to planning ship trajectory with some of the assumption of game theory. For given positions and motion parameters the method finds a near optimal set of safe trajectories of all ships involved in an encounter. This paper presents framework of the method and its development. Additionally, selected...

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  • Tracking of the broadband source of the underwater noise in the very shallow water conditions

    Publication

    The paper contains the result s, both theoretical and experimental , connected with the tracking of the underwater noise source as small ships, pontoon , diver and so on. The pro blem of security in the shallow water area is the challenge for underwater acousticians. In this paper there is take n into account the detection of the sources that move on the surface of the sea or underwater in shallow...

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  • Combined cold supply system for ship application based on low GWP refrigerants - Thermo-economic and ecological analyses

    Publication

    - ENERGY CONVERSION AND MANAGEMENT - Year 2022

    The withdrawal of popular high-GWP refrigerants will significantly affect maritime industry. Refrigeration and air conditioning systems currently used on ships are not ready to fulfil future limitations. Therefore, there is a need for system, which will operate with low-GWP refrigerants and at the same time will be efficient and reliable in difficult environmental conditions. This paper explains the concept of a cold supply system,...

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  • AC Motor Voltage and Audible Noise Dataset

    Publication

    - Year 2022

    The dataset titled AC motor voltage and audible noise waveforms in ship’s electrical drive systems with frequency converters contains the voltage and sound measurement results recorded in a marine frequency controlled AC drive system. The dataset is part of research focussing on the impact of the ship’s electrical drive systems with frequency converters on vibrations and the level of audible noise on ships. The dataset allows the...

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  • In Search of Naval Beauty. Historical Study of Ship Architecture

    Publication

    - Year 2018

    Designing ships is no mean achievement. In the old days, constructors focused on making their ships visually appealing, while paying scant regard to the living conditions of the crew. Such an approach reflected the state of the art in ship building at the time as well as the social order prevalent in those days. A breakthrough came no earlier than at the turn of the 19th / 20th centuries. The industrial revolution brought along...

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  • Diagnostics in ballast water management

    Publication
    • M. Bielski
    • J. Wachowicz
    • R. Bielski
    • A. Arkadiusz
    • J. Hendra

    - Year 2018

    . Diagnostics in ballast water management is the main remedy to protect against the threat of spreading invasive species that can be carried in ships' ballast tanks. This phenomenon is getting better known and understood. New and more effective methods of preventing threats related to this are being developed. Procedures are created to ensure environmental safety in the face of ever-increasing transport by sea. The article characterizes...

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  • Heuristic Method of Safe Manoeuvre Selection Based on Collision Threat Parameters Areas

    This paper is a continuation of papers dedicated to a radar-based CTPA (Collision Threat Parameters Area) display designed to support safe manoeuvre selection. The display visualizes all the ships in an encounter and presents situational overview from the own ship’s point of view. It calculates and displays information on unsafe or unrealistic own ship’s course & speed allowing a user to select a safe manoeuvre. So far only the...

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  • Testing the impact of simplifications adopted in models describing wave loads on ship

    Publication

    - Year 2011

    The wave-ship system in naval architecture is generally assumed to be a linear one. This allows for the computation of a transfer function of ship response to waves including wave loads on ship. The transfer function and the wave spectral density function enable the development of the stochastic process of wave loads on ship, corresponding to the irregular wave generating that loads. If the mathematical models of wave load transfer...

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  • Testing the impact of simplifications adopted in models describing wave loads on ship

    Publication

    - Year 2012

    The wave-ship system in naval architecture is generally assumed to be a linear one. This allows for the computation of a transfer function of ship response to waves including wave loads on ship. The transfer function and the wave spectral density function enable the development of the stochastic process of wave loads on ship, corresponding to the irregular wave generating that loads. If the mathematical models of wave load transfer...

  • Experimental Research on Insufficient Water Lubrication of Marine Stern Tube Journal Bearing with Elastic Polymer Bush

    Publication

    Water-lubricated bearings with polymer bushes are steadily gaining popularity due to their advantages, including environmental friendliness, relatively simple construction and long-term operation. Nevertheless, in practice instances of damage to such bearings occur due to insufficient or absent flow of the lubricating agent. In this study, experimental tests established that elastic polymer bush bearing is capable of operating...

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  • SAILING ROUTE PLANNING METHOD CONSIDERING VARIOUS USER CATEGORIES

    Publication

    The article describes the methodology related to determining the multi-criteria routes for sailing ships. Details of sea area discretisation and discretisation of the description of the sailing vessel properties and manoeuvring principles are shown. User requirements were specified (for five different categories of users) and on this basis the criteria for selecting the most suitable shipping route were formulated. The presented...

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  • DETERMINATION OF SEAKEEPING PERFORMANCE FOR A CASE STUDY VESSEL BY THE STRIP THEORY METHOD

    The increase of seakeeping performance is of particular importance for car and passenger ferries, service ships in the gas and oil extraction industry and offshore wind power farm industry, as well as for special purpose ships (including military applications). In the water areas of the Baltic Sea, North Sea, and Mediterranean Sea, which are characterised by a short and steep wave, the hull shape has a substantial impact on the...

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  • The spatial planning of industrial areas in an urbanized area for cargo, in the development of inland waterway transport

    Publication

    - E3S Web of Conferences - Year 2018

    Spatial planning, taking into account the configuration of the surface, i.e. its shape (relief) and the presence and mutual location of objects and points of characteristic water ports, is a derivative of several natural, economic, market, technical, social and political factors. It depends on the destination port, the planned structure of trade in cargo, the forecasted traffic of ships, passageways, the technology of reloading...

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  • Importance of model tests in design and operation of watercraft for example CTO

    Publication

    Ship Hydromechanics Division is a specialized research and development department of Ship Design and Research Centre conducting tests and research in the field of hydromechanics, connected with design and operation of ships and other floating structures, in scope of: predictions, numerical analyses, designs of - hull shape optimized with respect to the ship’s functions with the application of modern design tools, screw propellers...

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  • Case study of masts damage of the sail training vessel POGORIA

    Publication

    - ENGINEERING FAILURE ANALYSIS - Year 2011

    Artykuł przedstawia opis i analizę przyczyn zdarzenia polegającego na utracie masztów w lipcu 2009 przez barkentynę sts ''POGORIA'' w trakcie regat Tall Ships Race 2009. Przedstawiono podstawowe okoliczności stanowiące tło zdarzenia, dokonano anlizy przyczyn w skali globalnej, zaprezentowano analizę szczegółową utraty nośności konstrukcji stalowej, a na tym tle wypunktowano szczegółowe przyczyny leżące u źródeł wypadku. We wnioskach...

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  • Comparison of Selection Schemes in Evolutionary Method of Path Planning

    Publication

    - LECTURE NOTES IN COMPUTER SCIENCE - Year 2011

    This article compares an impact of using various selection schemes on the quality of the solution for the problem of planning the path for a moving object using the evolutionary method. In study case problem of avoiding collisions at sea is analyzed. The modelled environment includes static constraints (lands, canals, etc.) and dynamic objects (moving ships). Article analyses behaviour of selection schemes in two similar environments...

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  • Implementation of the digital receiver in multibeam long-range sonar

    Publication

    The article presents the implementation of a digital receiver in multibeam long - range sonar. Developed by the authors of the article, the implementation was part of sonar modernisation on large Polish Navy ships. The article explains the structure of the receiver, its design details and requirements affecting the architecture. The technical solutions regarding the equipment and signal processing algorithms for determining receiving...

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  • Wojciech Litwin dr hab. inż.

    1992÷1996 - study on Mechanical Department at Gdansk University of Technology1996 – employed in the Faculty of Ocean Engineering and Ship Technology at the Gdansk University of Technology2004 – PhD2014 – habilitation2016 - vice dean for science at Faculty of Ocean Engineering2020 - dean of the Faculty of Ocean Engineering2021 - head of Institute of Naval Architecture He participated in a number of designing and research programs...

  • Ship Resistance Prediction with Artificial Neural Networks

    Publication

    - Year 2015

    The paper is dedicated to a new method of ship’s resistance prediction using Artificial Neural Network (ANN). In the initial stage selected ships parameters are prepared to be used as a training and validation sets. Next step is to verify several network structures and to determine parameters with the highest influence on the result resistance. Finally, other parameters expected to impact the resistance are proposed. The research utilizes...

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  • Evolutionary Sets of Safe Ship Trajectories: problem dedicated operators

    The paper presents the optimization process of the evolutionary sets of safe ship trajectories method, with a focus on its problem-dedicated operators. The method utilizes a customized evolutionary algorithm to solve a constrained optimization problem. This problem is defined as finding a set of cooperating trajectories (a set is an evolutionary individual) of all the ships involved in the encounter situation. The resulting trajectories...

  • Marine Fuel Sulphur Limit Impact on Air Pollution

    The article presents calculation of Sulphur oxides percentage drop rate in marine industry recorded after 01.01.2020 when new limits, provided by International Maritime Organizations legislation, became effective. Ships’ SOx global emission was estimated and compared between 4th quarter 2019 and 1st quarter 2020. For more accurate estimation 3 seaside cities with big harbors were selected for statistical analysis. Noticeable...

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  • Strucutral steel - tensile test results

    Open Research Data
    open access

    Modern floating structures such as ships, oil platforms and offshore wind towers are built mostly of structural steel. It is a material that is subject to requirements which, when met, allows the construction and safe operation of the structure throughout its entire work cycle. One of the basic criteria that a material must meet is its strength. The...

  • Technological solutions for boosting hydrogen role in decarbonization strategies and net-zero goals of world shipping: Challenges and perspectives

    Publication
    • A. T. Hoang
    • A. Pandey
    • F. J. Martinez De Osés
    • W. Chen
    • Z. Said
    • K. H. Ng
    • Ü. Ağbulut
    • W. Tarełko
    • A. I. Ölçer
    • X. P. Nguyen

    - RENEWABLE & SUSTAINABLE ENERGY REVIEWS - Year 2023

    Facing the problems concerning greenhouse gas (GHG) emissions from international ocean shipping has meant that the latest regulations of the International Maritime Organization, issued on 1st January 2023, have come into force, with the aim of reducing GHG emissions from maritime activities. Hydrogen has been suggested as an alternative fuel to achieve decarbonization ambitions in the near future. Although hydrogen has been investigated...

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  • ZASTOSOWANIE MACIERZY PSEUDO ODWROTNEJ W METODACH ALOKACJI PĘDNIKÓW UKŁADU DYNAMICZNEGO POZYCJONOWANIA STATKU

    Układy kontroli alokacji pędników stanowią ważną część systemów dynamicznego pozycjonowania na statku. Określają one sygnały sterujące nastawami pędników, na podstawie uogólnionego wektora sił wzdłużnej, poprzecznej i momentu skręcającego, uzyskiwanych z prawa sterowania. W artykule przedstawiono wybrane algorytmy kontroli alokacji pędników, różniące się sposobem wyznaczania macierzy pseudo odwrotnej oraz algorytm bezpośredniej...

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  • The statistic properties of rms voltage and frequency in the ship's electrical power system

    Open Research Data
    open access

    The dataset is a part of the research results on the quality of supply voltage on bus bars of the main switchboard of the ship's electrical power system in different states of ship exploitation. The attached dataset contains the results of a statistical analysis of rms voltage and frequency in the ship's electrical power system. The following statistical...

  • Evolutionary Sets of Safe Ship Trajectories: Evaluation of Individuals

    The paper presents a description of the evaluation phase of the Evolutionary Sets of Safe Ship Trajectories method. In general, the Evolutionary Sets of Safe Ship Trajectories method combines some of the assumptions of game theory with evolutionary programming and finds an optimal set of cooperating trajectories of all ships involved in an encounter situation. While developing a new version of this method, the authors decided to...

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  • Data fusion of GPS sensors using Particle Kalman Filter for ship dynamic positioning system

    Publication

    Depending on standards and class, dynamically positioned ships make use of different numbers of redundant sensors to determine current ship position. The paper presents a multi-sensor data fusion algorithm for the dynamic positioning system which allows it to record the proper signal from a number of sensors (GPS receivers). In the research, the Particle Kalman Filter with data fusion was used to estimate the position of the vessel....

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  • Simplified Method of Modelling Behaviour of Ship in Waves with Partially Flooded Compartments

    Publication
    • P. Szulczewski

    - Transactions on Maritime Science-ToMS - Year 2021

    This paper contains a description of a numerical model for calculating behaviour of ships in waves. There are many models available, but the one described here can be characterised with a set of parameters that have a decisive impact on the final values of roll motion amplitude and frequency. In this paper, it is shown how a fitting of a standard-shape hull characterised by certain readily available parameters affects...

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  • METHOD FOR SHIP'S ROLLING PERIOD PREDICTION WITH REGARD TO NON-LINEARITY OF GZ CURVE

    Publication

    The paper deals with the problem of prediction of the rolling period. A special emphasis is put on the practical application of the new method for rolling period prediction with regard to non-linearity of the GZ curve. The one degree-of-freedom rolling equation is applied with using the non-linear stiffness moment and linear damping moment formulas. A number of ships are considered to research the discrepancies between the pending...

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  • RESHAPING THE GDANSK HARBOR –THE CONTINUOUS PROCESS

    Gdańsk is the harbour city with a history of more than 1000 years. For many centuries the harbour structures were evolving within the central part of the historic city centre, and – in result – a specific urban structures associated with these functions were created. But the evolution of the maritime technology as well as new needs regarding servicing the ships and cargo-handling activities effected in creation of the more modern...

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  • Nowoczesne układy przekształtników wielopoziomowych do zasilania statków z lądu

    W artykule poruszono tematykę zasilania statków zacumowanych w porcie z lądowej sieci elektroenergetycznej poprzez wykorzystanie nowoczesnych konstrukcji przekształtników energoelektronicznych. W treści pracy zaprezentowano porównanie dwóch topologii wysokonapięciowych przekształtników wielopoziomowych. Porównano konstrukcje przekształtników z klasycznym transformatorem wielouzwojeniowym oraz z transformatorami wysokoczęstotliwościowymi.

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  • HYBRID ENERGY SYSTEM FOR A CLASSIC SHIP POWER PLANT

    Publication

    The article presents a brief overview of hybrid energy systems used on ships. The area of their application is outlined. The benefits of using such systems are also indicated. Then, the classic ship power plant is defined. The most important part of the article is a proposal how to modify a classic engine room by using a hybrid energy system. The idea is: to accumulate a part of electricity in areas where it is allowed to burn...

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  • Evolutionary Sets of Safe Ship Trajectories: Evaluation of Individuals

    Publication

    The paper presents a description of the evaluation phase of the Evolutionary Sets of Safe Ship Trajectories method. In general, the Evolutionary Sets of Safe Ship Trajectories method combines some of the assumptions of game theory with evolutionary programming and finds an optimal set of cooperating trajectories of all ships involved in an encounter situation. While developing a new version of this method, the au-thors decided...

  • Environmental Risk Assessment of WWII Shipwreck pollution

    Publication

    The pollution of the sea is a global problem that has arisen as a consequence of the industrialization of the world and the intense transportation of crude oil and the products of its refinement. As sailing vessels were replaced by motor propelled ships towards the end of the 19th century, a new source of sea water pollution came into being. Every emergency involving a tanker carrying crude oil and its products is a potential source...

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  • Accident susceptibility index for a passenger ship-a framework and case study

    Publication
    • J. Montewka
    • T. Manderbacka
    • P. Ruponen
    • M. Tompuri
    • M. Gil
    • S. Hirdaris

    - RELIABILITY ENGINEERING & SYSTEM SAFETY - Year 2022

    The continuous monitoring and assessment of operational vulnerability and accident susceptibility of passenger ships is crucial from the perspective of ship and passenger safety. Despite the existing solutions for vulnerability monitoring, stemming mainly from watertight door operations, a comprehensive framework for accident susceptibility assessment and monitoring is missing in the literature. Therefore, this paper offers a...

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  • PODEJŚCIE WARIANTOWE WE WSTĘPNYM PROJEKTOWANIU STATKÓW Variant methods approach to the preliminary ship design.

    Publication

    Klasyczna metoda projektowania okrętów jest metodą iteracyjną, bazującą na zgromadzonym doświadczeniu ze statków już zbu-dowanych. Natomiast w przypadku statku całkowicie nowego typu, bez „posagu wcześniejszych doświadczeń”, projektowanie polega na opracowaniu szeregu równoległych, wariantowych rozwiązań z wykorzystaniem optymalizacji. Artykuł wskazuje wybrane metody projektowe wykorzystujące optymalizacje, używane we wstępnym...

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  • Paweł Tysiąc dr inż.

    He was born on March 25, 1992 in Gdańsk. After graduating from Junior High School No. 32, he attended the VIII Liceum Ogólnokształcące im. National Education Commission in Gdańsk, classes with a mathematical and geographical profile, obtaining a secondary school-leaving examination certificate in 2011. Then, in 2011-2016, he continued his studies at the Faculty of Civil and Environmental Engineering of the Gdańsk University of...