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Katalog Publikacji
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Review of ship safety domains: Models and applications
PublikacjaShip safety domain is a term which is widely used in research on collision avoidance and traffic engineering among others. Classic ship domains have been compared in multiple reports. However, up till now there has been no work summing up contemporary research in this field. The paper offers a systematic and critical review of the newer ship domain models and related research. It discusses multiple differences in approach to ship...
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An analysis of domain-based ship collision risk parameters
PublikacjaAccording to a lot of contemporary research on ship collision avoidance the classic approach parameters – distance at closest point of approach (DCPA) and time to the closest point of approach (TCPA) – are not sufficient for estimating ship collision risk and for planning evasive manoeuvres. Consequently new measures are introduced, often utilizing the concept of a ship domain. Their drawback, up to this point, was the lack of...
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A unified measure of collision risk derived from the concept of a ship domain
PublikacjaW artykule zaprezentowano nową miarę ryzyka kolizji dwóch statków, wywiedzioną z koncepcji domeny statku. Jej prostota oraz fakt, że uwzględnia ona kursy obydwu statków czynią ją dobrą alternatywą dla często stosowanego pojęcia odległości największego zbliżenia. Miara ta jest elastyczna, tzn. można korzystać z niej w powiązaniu z dowolną, zadaną domeną statku. Szczegółowo przedstawiono wyprowadzenia wszystkich niezbędnych wzorów...
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Experimental research on water lubricated marine stern tube bearings in conditions of improper lubrication and cooling causing rapid bush wear
PublikacjaWater lubricated bearings are popular in sliding bearings of marine propeller shafts, turbines and pump shafts. Such popularity is partly due to their simple construction which also means a relatively affordable price. In practical experience one may also observe cases of rapid wear or even malfunctions of this bearings, some of which may be caused by insufficient flow of lubricant leading to overheating. The conducted...
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Experimental research on water lubricated three layer sliding bearing with lubrication grooves in the upper part of the bush and its comparison with a rubber bearing
Publikacjacomposite. Eachofitslayershasanimportantfunction.Speciallypreparedslidingsurfaceensures minimum resistance.Followingrunning-initssmoothnessbecomesveryhighandthebearingmay continue workingunder fluid lubricationregime.NBRlayerensuresbearingelasticity,goodvibration damping propertiesandinsusceptibilitytoshaftaxismisalignment.Theexternalbrasslayermakes fitting thebearingeasier. Experiment resultsoftheconductedresearchwerecomparedwiththoseforarubberbearingof similar...
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Ship domain applied to determining distances for collision avoidance manoeuvres in give-way situations
PublikacjaShip 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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Evolutionary Sets Of Safe Ship Trajectories: A New Approach To Collision Avoidance
PublikacjaThe paper introduces a new method of solving multi-ship encounter situations for both open waters and restricted water regions. The method, called evolutionary sets of safe trajectories combines some of the assumptions of game theory with evolutionary programming and aims to find optimal set of safe trajectories of all ships involved in an encounter situation. In a two-ship encounter situation it enables the operator of an on-board...
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A new method of ship routing on raster grids, with turn penalties and collision avoidance
PublikacjaArtykuł przedstawia nowy algorytm znajdowania optymalnych tras na siatkach rastrowych. Szczegółowo opisano zastosowane struktury danych, dzięki którym algorytm ma liniową złożoność obliczeniową. Na podstawie algorytmu opracowano metodę wyznaczania tras dla statków, uwzględniającą kwestie unikania kolizji z innymi statkami i przeszkodami nawigacyjnymi.Przedstawiono dwa warianty metody, dedykowane odpowiednio systemom pokładowym...
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Influence of local bush wear on water lubricated sliding bearing load carrying capacity
PublikacjaOne of main problems concerning water-lubricated bearings is their durability. There are known cases of bearings with life time measured in decades, and some, whose refurbishment was necessary just days after start-up. Obtaining stable fluid film friction plays key role in the durability of these bearings. Unfortunately, their load-carrying capacity is limited due to water's low-viscosity. The conducted experimental...
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On evolutionary computing in multi-ship trajectory planning, Applied Intelligence
PublikacjaThe paper presents the updated version of Evolutionary Sets of Safe Ship Trajectories: a method which applies evolutionary algorithms and some of the assumptions of game theory to solving ship encounter situations. For given positions and motion parameters of the ships,the method finds a near optimal set of safe trajectories of all ships involved in an encounter. The method works in real time and the solutions must be returned...
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A method of determining and visualizing safe motion parameters of a ship navigating in restricted waters
PublikacjaThe paper presents a method of displaying ship collision avoidance information which is based on an unconventional Collision Threat Parameters Area (CTPA) technique. The solution presented here extends CTPA's functionality from past works by supporting navigation in restricted waters and handling ship domains analytically instead of numerically. It visualizes potential navigational threats as well as possible collision avoidance...
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Determining and visualizing safe motion parameters of a ship navigating in severe weather conditions
PublikacjaThe paper presents a method of determining, organizing and displaying ship collision avoidance information, which is based on the Collision Threat Parameters Area (CTPA) technique. The method makes it possible to visualize navigational threats as well as possible collision avoidance manoeuvres. The solution is focused on supporting navigation in severe weather conditions. Normally collision avoidance decisions are made taking into...
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Water-lubricated stern tube bearing - experimental and theoretical investigations of thermal effects
PublikacjaThe paper presents research results of thermal phenomena accompanying operation of a water-lubricated stern tube bearing with axial grooves. Experimental tests revealed, that intensity of forced axial flow has strong influence on bush temperature. Numerical simulations focused on investigation of the thermal phenomena under operation of water-lubricated journal bearing showed, that restricted axial flow promotes backflow of the...
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Properties comparison of rubber and three layer PTFE-NBR-bronze water lubricated bearings with lubricating grooves along full bush circumference based on experimental tests
PublikacjaWater lubricated bearings have been in industrial use for well over a century. During the last decade their traditional range has been expanded with new, modern products. Despite that fact, certain solutions continue to employ the standard rubber bearing with lubricating grooves located along entire bush circumference. The work presents experimental research conducted on comparable sliding bearings with lubrication grooves along...
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Preference-based evolutionary multi-objective optimization in ship weather routing
PublikacjaIn evolutionary multi-objective optimization (EMO) the aim is to find a set of Pareto-optimal solutions. Such approach may be applied to multiple real-life problems, including weather routing (WR) of ships. The route should be optimal in terms of passage time, fuel consumption and safety of crew and cargo while taking into account dynamically changing weather conditions. Additionally it must not violate any navigational constraints...
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Evolutionary Sets of Safe Ship Trajectories Within Traffic Separation Schemes
PublikacjaThe paper presents the continuation of the author's research on Evolutionary Sets of Safe Ship Trajectories (ESoSST) methodology. In an earlier paper (Szlapczynski, 2011) the author described the foundations of this methodology, which used Evolutionary Algorithms (EA) to search for an optimal set of safe trajectories for all the ships involved in an encounter. The methodology was originally designed for open waters or restricted...
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Evolutionary Planning of Safe Ship Tracks in Restricted Visibility
PublikacjaThe paper presents the continuation of the author's research on ship track planning by means of Evolutionary Algorithms (EA). The presented method uses EA to search for an optimal set of safe tracks for all ships involved in an encounter. Until now the method assumed good visibility – compliance with standard rules of the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS, 1972). However, in restricted...
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Water-lubricated bearings of ship propeller shafts - problems, experimental tests and theoretical investigations
PublikacjaW pracy przedstawiono problemy związane z projektowaniem, montażem i ekspolatcją smarowanych wodą łożysk okrętowych wałów głównych.Przedstawiono wyniki prowadzonych prac badawczych ekperymntalnych i obliczeń.
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Influence of main design parameters of ship propeller shaft water-lubricated bearings on their properties
PublikacjaW artykule omówiono wpływ głównych parametrów konstrukcyjnych i eksploatacyjnych takich jak wielkość luzu łożyskowego, własności materiału panwi, stanu powierzchni skojarzenia ślizgowego oraz temperatury i zasolenia wody na nośność hydrodynamiczną łożyska okrętowego wału śrubowego smarowanego wodą.
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A Target Information Display for Visualising Collision Avoidance Manoeuvres in Various Visibility Conditions
PublikacjaThe paper introduces a new approach to displaying information on targets. The proposed display visualises three types of information: targets’ motion parameters (typical for target tracking), combinations of own course and speed which collide with those targets (typical for Collision Threat Parameters Area display by Lenart (1983)) and combinations of own course and speed which are not compliant with COLREGS in this case (based...
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Water-Lubricated Sintered Bronze Journal Bearings—Theoretical and Experimental Research
PublikacjaWater lubricated bearings are used from many years in shipbuilding, hydro power and other industries because of their advantages such as: extensive serviceable life, low coefficient of friction, longevity of shaft sleeve, good abrasion resistance, low maintenance required, unit simplicity, no danger of pollution and low price. Various types of water lubricated sliding bearings have been tested at the Technical University of Gdansk...
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High performance super-twisting sliding mode control for a maritime autonomous surface ship (MASS) using ADP-Based adaptive gains and time delay estimation
PublikacjaThis research addresses two kinds of problems related to optimal trajectory tracking of a Maritime Autonomous Surface Ship (MASS): those caused by the time-varying external disturbances including winds, waves and ocean currents as well as those resulting from inherent dynamical uncertainties. As the paper shows, an accurate and robust optimal controller can successfully deal with both issues. An improved Optimal Adaptive Super-Twisting...
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Experimental Research on the Energy Efficiency of a Parallel Hybrid Drive for an Inland Ship
PublikacjaThe growing requirements for limiting the negative impact of all modes of transport on the natural environment mean that clean technologies are becoming more and more important. The global trend of e-mobility also applies to sea and inland water transport. This article presents the results of experimental tests carried out on a life-size, parallel diesel-electric hybrid propulsion system. The eciency of the propulsion system was...
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A Framework of A Ship Domain-Based Near-Miss Detection Method Using Mamdani Neuro-Fuzzy Classification
PublikacjaSafety analysis of navigation over a given area may cover application of various risk measures for ship collisions. One of them is percentage of the so called near- miss situations (potential collision situations). In this article a method of automatic detection of such situations based on the data from Automatic Identification System (AIS), is proposed. The method utilizes input parameters such as: collision risk measure based...
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Customized crossover in evolutionary sets of safe ship trajectories
PublikacjaThe paper presents selected aspects of evolutionary sets of safe ship trajectories-a method which applies evolutionary algorithms and some of the assumptions of game theory to solving ship encounter situations. For given positions and motion parameters of the ships, the method finds a near optimal set of safe trajectories of all ships involved in an encounter. The method works in real time and the solutions must be returned within...
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Framework of an Evolutionary Multi-Objective Optimisation Method for Planning a Safe Trajectory for a Marine Autonomous Surface Ship
PublikacjaThis paper represents the first stage of research into a multi-objective method of planning safe trajectories for marine autonomous surface ships (MASSs) involved in encounter situations. Our method applies an evolutionary multi-objective optimisation (EMO) approach to pursue three objectives: minimisation of the risk of collision, minimisation of fuel consumption due to collision avoidance manoeuvres, and minimisation of the extra...
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A Ship Domain-Based Method of Determining Action Distances for Evasive Manoeuvres in Stand-On Situations
PublikacjaA ship encounter can be considered safe if neither of ships’ domains (defined areas around ships) is intruded by other ships. Published research on this includes optimising collision avoidancemanoeuvres fulfilling domain-based safety conditions.However, until recently there was no method, using ship’s domain to determine exact moment when a particular collision avoidance manoeuvre can still be successfully performed. The authors...
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Marine propeller shaft bearings under low-speed conditions: water vs. oil lubrication
PublikacjaThe bearings used in shipbuilding, hydropower, and water pumps have undergone a metamorphosis in recent decades. Because of environmental regulations, lubrication with grease or mineral oil is prohibited. Thus, the standard solutions include water-lubricated bearings with polymer bushings or sealed systems lubricated with oil. When properly designed, assembled, and operated, bearings can operate reliably for years. However, specific...
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Supporting Navigator's Decisions By Visualizing Ship Collision Risk
PublikacjaW artykule wprowadzono metodę wizualizacji, która umożliwia nawigatorowi oszacowanie ryzyka kolizji i (w razie konieczności) wybór manewru antykolizyjnego. Metoda jest oparta na wcześniejszej metodzie CTPA, uwzględnia dowolną zadaną domenę statku i jest wystarczająco szybka do zastosowania w okrętowych systemach wspierania decyzji nawigatora.
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Model Predictive Super-Twisting Sliding Mode Control for An Autonomous Surface Vehicle
PublikacjaThis paper presents a new robust Model Predictive Control (MPC) algorithm for trajectory tracking of an Autonomous Surface Vehicle (ASV) in presence of the time-varying external disturbances including winds, waves and ocean currents as well as dynamical uncertainties. For fulfilling the robustness property, a sliding mode control-based procedure for designing of MPC and a super-twisting term are adopted. The MPC algorithm has been...
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Multi-objective weather routing of sailing vessels
PublikacjaThe paper presents a multi-objective deterministic method of weather routing for sailing vessels. Depending on a particular purpose of sailboat weather routing, the presented method makes it possible to customize the criteria and constraints so as to fit a particular user’s needs. Apart from a typical shortest time criterion, safety and comfort can also be taken into account. Additionally, the method supports dynamic weather data:...
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Multi-objective weather routing of sailboats considering wave resistance
PublikacjaThe article presents a method to determine the route of a sailing vessel with the aid of deterministic algorithms. The method assumes that the area in which the route is to be determined is limited and the basic input data comprise the wind vector and the speed characteristic of the vessel. Compared to previous works of the authors, the present article additionally takes into account the effect of sea waves with the resultant resistance...
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Multi-source-supplied parallel hybrid propulsion of the inland passenger ship STA.H. Research work on energy efficiency of a hybrid propulsion system operating in the electric motor drive mode
PublikacjaIn the Faculty of Ocean Engineering and Ship Technology, Gdansk University of Technology, design has recently been developed of a small inland ship with hybrid propulsion and supply system. The ship will be propelled by a specially designed so called parallel hybrid propulsion system. The work was aimed at carrying out the energy efficiency analysis of a hybrid propulsion system operating in the electric motor drive mode and at...
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Dynamically positioned ship steering making use of backstepping method and artificial neural networks
PublikacjaThe article discusses the issue of designing a dynamic ship positioning system making use of the adaptive vectorial backstepping method and RBF type arti cial neural networks. In the article, the backstepping controller is used to determine control laws and neural network weight adaptation laws. e arti cial neural network is applied at each time instant to approximate nonlinear functions containing parametric uncertainties....
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Energy Demand of Short-Range Inland Ferry with Series Hybrid Propulsion Depending on the Navigation Strategy
PublikacjaInterest in hybrid propulsion systems that can be used on small vessels has increased significantly in recent years. They can replace inefficient and environmentally burdensome conventional systems based on diesel engines. Hybrid propulsion has many advantages such as high energy efficiency and virtually noiseless operation, and therefore it fits well with the current trends of “green shipping” and “zero emission”. The aim of the...
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Design Methodology for Small Passenger Ships On the Example of the Ferryboat Motława 2 Driven by Hybrid Propulsion System
PublikacjaDynamic development in practically all elds of science and engineering has not passed over shipbuilding . In last years , engineers got to their use computer soware which makes it possible to perform strength and hydrodynamic calculations as well as to visualize design projects in 3 D space [1-4]. At their disposal they have full spectrum of modern solutions associated with the use of advanced materials and technologies [5-7]....
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ENERGY EFFICIENT AND ENVIRONMENTALLY FRIENDLY HYBRID CONVERSION OF INLAND PASSENGER VESSEL
PublikacjaThe development and growing availability of modern technologies, along with more and more severe environment protection standards which frequently take a form of legal regulations, are the reason why attempts are made to find a quiet and economical propulsion system not only for newly built watercraft units, but also for modernised ones. Correct selection of the propulsion and supply system for a given vessel affects significantly...
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Stability Analysis of the Floating Offshore Wind Turbine Support Structure of Cell Spar Type During its Installation
PublikacjaThe article presents the results of selected works related to the wider subject of the research conducted at the Faculty of Ocean Engineering and Ship Technology of the Gdansk University of Technology, which concerns design and technology of construction, towing, and settlement on the seabed, or anchoring, of supporting structures for offshore wind farms. As a result of this research, several designs of this type of objects were...
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REVIEW OF WEATHER FORECAST SERVICES FOR SHIP ROUTING PURPOSES
PublikacjaWeather data is nowadays used in a variety of navigational and ocean engineering research problems: from the obvious ones like voyage planning and routing of sea-going vessels, through the analysis of stability-related phenomena, to detailed modelling of ships’ manoeuvrability for collision avoidance purposes. Apart from that, weather forecasts are essential for passenger cruises and fishing vessels that want to avoid the risk...
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APPLICATION OF APRIORI ALGORITHM IN THE LAMINATION PROCESS IN YACHT PRODUCTION
PublikacjaThe article specifies the dependence of defects occurring in the lamination process in the production of yachts. Despite great knowledge about their genesis, they cannot be completely eliminated. Authentic data obtained through cooperation with one of the Polish yacht shipyards during the years 2013–2017 were used for the analysis. To perform a simulation, the sample size was observed in 1450 samples, consisting of 6 models of...
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ENERGY EFFICIENT SMALL INLAND PASSENGER SHUTTLE FERRY WITH HYBRID PROPULSION - CONCEPT DESIGN, CALCULATIONS AND MODEL TESTS
PublikacjaIn recent years, there has been a significant development in “green” and energy efficient propulsion systems, which fits into the general trend of environmentally friendly “green shipping”. The pursued goal is to construct a safe passenger ship that is low in energy demand and equipped with a highly energy efficient, emission-free propulsion system. The paper presents main problems encountered by designers of a small, hybrid-powered...
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Planning emergency manoeuvres
PublikacjaW artykule poruszono problem planowania manewrów ostatniej szansy i zmian planowanej trajektorii statku w przypadku nieoczekiwanych zachowań obiektów obcych. Wprowadzono dwie metody. Pierwsza z nich jest odpowiedzialna za monitorowanie parametrów obiektów obcych, szacowanie prawdopodobieństwa nieprzepisowego zachowania i aktualizację trajektorii statku własnego. Druga to narzędzie wizualizacyjne umożliwiające nawigatorowi szybki...
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Robust Model Predictive Control for Autonomous Underwater Vehicle – Manipulator System with Fuzzy Compensator
PublikacjaThis paper proposes an improved Model Predictive Control (MPC) approach including a fuzzy compensator in order to track desired trajectories of autonomous Underwater Vehicle Manipulator Systems (UVMS). The tracking performance can be affected by robot dynamical model uncertainties and applied external disturbances. Nevertheless, the MPC as a known proficient nonlinear control approach should be improved by the uncertainty estimator...
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Influence of local bush wear on properties of water lubricated marine stern tube bearings
PublikacjaW artykule przedstawiono propozycję metody obliczania łożysk ślizgowych smarowanych cieczą o niskiej lepkości (wodą) w których doszło do lokalnego zużycia panwi. Proponowana metoda uwzględnia sprężystą deformację panwi (model EHL) oraz zmianę geometrii będącą wynikiem zużycia.
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DESIGN AND STRENGTH CALCULATIONS OF THE TRIPOD SUPPORT STRUCTURE FOR OFFSHORE POWER PLANT
PublikacjaThe support structure being the object of the analysis presented in the article is Tripod. According to the adopted assumptions, it is a foundation gravitationally set in the water region of 60 m in depth, not fixed to the seabed, which can be used for installing a 7MW wind turbine. Due to the lack of substantial information on designing and strength calculations of such types of structures in the world literature, authors have...
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Developing Methodology for Model Tests of Floating Platforms in Low -Depth Towing Tank
PublikacjaThe paper presents two different methods of physical modeling of semi-submersible platform mooring system for research in low depth towing tank. The tested model was made in the scale of 1:100 resembling the "Thunder Horse" platform moored in the Gulf of Mexico at a depth of 1,920 m. Its mooring system consisted of 16 semi-taut mooring lines (chain-wire-chain) spaced starshape and attached at the bottom to suction piles. The tests...
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Visualization of a lifeboat motion during lowering along ship’s side
PublikacjaThis paper presents description of a computer program for motion visualization of a lifeboat lowered along ship’s side. The program is a post-processor which reads results of numerical calculations of simulated objects’ motions. The data is used to create scene composed of 3D surfaces to visualize mutual spatial positions of a lifeboat, ship’s side and water waving surface. Since the numerical data contain description of a simulation...
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ANALYSIS OF IMPACT of SHIP model parameters on changes of control quality index in ship dynamic positioning system
PublikacjaIn this work there is presented an analysis of impact of ship model parameters on changes of control quality index in a ship dynamic positioning system designed with the use of a backstepping adaptive controller. Assessment of the impact of ship model parameters was performed on the basis of Pareto-Lorentz curves and ABC method in order to determine sets of the parameters which have either crucial, moderate or low impact on objective...
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Evolutionary sets of safe ship trajectories with speed reduction manoeuvres within traffic separation schemes
PublikacjaIn the previous paper the author presented the evolutionary ship trajectory planning method designed to support Traffic Separation Schemes (TSS). This time the extensions of this method are described which allow to combine evolutionary trajectory planning with speed reduction manoeuvres. On TSS regions with higher than usual density of traffic and smaller distances between ships, the course alterations alone are not always sufficient...
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Computational model for simulation of lifeboat motions during its launching from ship in rough seas
PublikacjaW artykule przedstawiono model obliczeniowy 3 D, opisujący ruch obiektu w 6 stopniach swobody (6DoF), do symulacji ruchu jedno- lub dwuzawiesiowej łodzi ratunkowej lub ratowniczej podczas opuszczania ze statku na wzburzonej wodzie. Jest to złożony model uwzględniający warunki morskie oraz elastyczność i własności tłumiące elementów i mechanizmów żurawika, liny oraz kadłuba łodzi. Ponadto przedstawiono przykładowe wyniki obliczeń...
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Design of Structure of Tension Leg Platform for 6 MW Offshore Wind Turbine Based On Fem Analysis
PublikacjaThe article presents the calculation and design stages of the TLP platform serving as a supporting construction of a 6 MW offshore wind turbine. This platform is designed to anchor at sea at a depth of 60 m. The authors presented the method of parameterization and optimization of the hull geometry. For the two selected geometry variants, the load and motion calculations of the platform subjected to wind, wave and current under...
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A Simulative Comparison of Ship Domains and Their Polygonal Approximations
PublikacjaThe paper investigates the impact of a precise ship domain shape on the size of collision avoidance manoeuvres. The considered collision avoidance manoeuvres include both course and speed alterations. Various ship domains are compared with their polygonal approximations, which vary in the number of points of a domain contour and placement of these points. The best of all considered approximations is determined in the course of...
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OPTIMISING RIG DESIGN FOR SAILING YACHTS WITH EVOLUTIONARY MULTIOBJECTIVE ALGORITHM
PublikacjaThe paper presents a framework for optimising a sailing yacht rig using Multi-objective Evolutionary Algorithms and for filtering obtained solutions by means of a Multi-criteria Decision Making method. A Bermuda sloop with discontinuous rig is taken under consideration as a model rig configuration. It has been decomposed into its elements and described by a set of control parameters to form a responsive model which can be used...
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Losses and energy efficiency of drive motors and systems
PublikacjaLosses and energy efficiency of every drive motor must be presented as functions of physical quantities independent of losses in the motor. Such quantities are speed and load required by the machine or device driven by the motor, changing in the drive operating field. Speed and load of the motor decide of the instantaneous useful power of the motor and also in a differentiated way of kinds and values of losses occurring in the...
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Losses and energy efficiency of drive motors and systems
PublikacjaLosses and energy efficiency of every drive motor must be presented as functions of physical quantities independent of losses in the motor. Such quantities are speed and load required by the machine or device driven by the motor, changing in the drive operating field. Speed and load of the motor decide of the instantaneous useful power of the motor and also in a differentiated way of kinds and values of losses occurring in the...
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Experimental research on marine oil-lubricated stern tube bearing
PublikacjaBearings of propeller shafts are very crucial elements of the propulsion system of each of the ships. The safety of shipping depends on their durability and reliability. The new legal restrictions mean that today we are looking for environmentally friendly solutions. That is why water-lubricated bearings are becoming more and more popular. So, will oil-lubricated shaft bearings belong to the past? The bearing with a white metal...
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Technology Concept of TLP Platform Towing and Installation in Waters with Depth of 60 m
PublikacjaThe article is part of the design and research work conducted at the Gdansk University of Technology, Faculty of Ocean Engineering and Ship Technology, in cooperation with a number of other research centres, which concerns offshore wind farms planned to be built in the Polish zone of the Baltic sea in the next years. One of most difficult tasks in this project is building suitable foundations for each power unit consisting of a...
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Selected Problems of Experimental Testing Marine Stern Tube Bearings
PublikacjaThis paper presents typical methods for conducting experimental tests on main shaft slide bearings. There are described their possible testing capabilities, advantages, drawbacks and limitations. Various testing methods were analyzed to find a solution able of providing a wide range of possible investigations at possibly acceptable limitations.
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Evolutionary approach to ship's trajectory planning within Traffic Separation Schemes
PublikacjaThe paper presents the continuation of the author's research on evolutionary approach to ship trajectory planning. While the general problem of the evolutionary trajectory planning has already been solved, no one has yet touched one of its specific aspects: evolutionary trajectory planning within Traffic Separation Schemes. Traffic Separation Scheme (TSS) is a traffic-management route-system complying with rules of the International...
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A CONCEPT DESIGN OF DIESEL – HYDRAULIC PROPULSION SYSTEM FOR PASSENGER SHIP INTENDED FOR INLAND SHALLOW WATER NAVIGATION
PublikacjaThis paper presents an analysis of environmental and technical conditions necessary for working out a possibly most favourable propulsion system for a two – segment passenger ship intended for navigation between Berlin and Kaliningrad. There are presented various types of propulsion systems for small ships as well as analyzed their possible applications and consequences. In this work there were taken into account system’s reliability,...
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Heuristic Method of Safe Manoeuvre Selection Based on Collision Threat Parameters Areas
PublikacjaThis 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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Searching for Critical Conditions During Lifeboat Launching – Simulations
PublikacjaThe article describes numerical simulations of the process of lifeboat launching at the ship’s side. The research is aimed at finding the values of ship motion parameters which appear to be most dangerous for people in the lowered lifeboat due to the generated accelerations. The simplified model of ship hull motion adopted at this research stage bases on a superposition of harmonic motions with given amplitudes and periods in six...
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Effect of the working liquid compressibility on the picture of volumetric and mechanical losses in a high pressure displacement pump used in a hydrostatic drive Part II Mechanical losses in a pump
PublikacjaŚciśliwość cieczy roboczej może znacząco zmienić wartości i proporcje współczynników strat objętościowych i mechanicznych w pompie wyporowej zastosowanej w układzie napędu hydrostatycznego. Wpływ ten jest szczególnie widoczny w trakcie pracy pod wysokim ciśnieniem a także wówczas, gdy występuje zapowietrzenie cieczy roboczej. W części II przedstawiono model matematyczny momentu strat mechanicznych w pompie oraz jego laboratoryjną...
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Theoretical and mathematical models of the torque of mechanical losses in a hydraulic rotational motor for hydrostatic drive
PublikacjaW pracy przedstawiono modele teoretyczne i matematyczne momentu strat mechanicznych występujących w silniku hydraulicznym obrotowym o stałej teoretycznej chłonności qMt silnika na obrót wału (o stałej teoretycznej objętości roboczej VMt silnika) i o zmiennej chłonności qMgv = bM qMt na obrót wału (o zmiennej geometrycznej objętości roboczej VMgv silnika). Modele mają służyć badaniom laboratoryjnym i symulacyjnym strat energetycznych...
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Investigation method and mathematical model of pressure losses in hydraulic rotary motor
PublikacjaTis paper presents a way of determining the coefcient k of the pressure losses Δp (fow drag) in internal ducts 8 Mp of SWSB-63 hydraulic motor. Te coefcient is determined at a fow rate equal to the theoretical capacity Q of the Pt pump feeding the motor , the losses are related to the nominal pressure p in the hydraulic system. Te investigations n followed a model of energy performance of hydraulic rotary motor, proposed by...
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SAILING ROUTE PLANNING METHOD CONSIDERING VARIOUS USER CATEGORIES
PublikacjaThe 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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Research on a control system based on stepping motor for ship's controllable pitch propellers
PublikacjaW artykule przedstawiono opis stanowiska laboratoryjnego do badania serwomechanizmów okrętowych śrub nastawnych małej mocy oraz opracowany układ sterowania zdalnego śruby z wykorzystaniem elektrycznego silnika krokowego. Przedstawiono także wyniki pierwszej serii badań układu sterowania śruby nieobciążonej dla skokowego zadawanych wartości skoku śruby przy dwóch różnych prędkościach obrotowych silnika krokowego.
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On power stream in motor or drive system
PublikacjaIn a motor or in a drive system the quantity of power increases in the direction opposite to the direction of power flow. Energy losses and energy efficiency of a motor or a drive system must be presented as functions of physical quantities independent of losses. Such quantities are speed and load. But the picture of power stream in a motor or in a drive system is presented in the literature in the form of traditional Sankey...
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NEW CONCEPT OF HYBRID PROPULSION WITH HYDROSTATIC GEAR FOR INLAND WATER TRANSPORT
PublikacjaThe article presents the development of author’s concept of a diesel/hydraulic propulsion system for inland watercraft. Due to specific nature of vessel navigation on rivers, classical propulsion systems with shaft lines can be effectively replaced by systems with hydraulic power transmission. A solution is also presented of a hybrid design with extra electric port having the form of a pumping system driven from a battery of accumulators....
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Mathematical model defining volumetric losses of hydraulic oil compression in a variable capacity displacement pump
PublikacjaThe objective of the work is to develop the capability of evaluating the volumetric losses of hydraulic oil compression in the working chambers of high pressure variable capacity displacement pump. Volumetric losses of oil compression must be determined as functions of the same parameters, which the volumetric losses due to leakage, resulting from the quality of design solution of the pump, are evaluated as dependent on and also...
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Small Vessel with Inboard Engine Retrofitting Concepts; Real Boat Tests, Laboratory Hybrid Drive Tests and Theoretical Studies
PublikacjaThe development of modern technologies and their increasing availability, as well as the falling costs of highly ecient propulsion systems and power sources, have resulted in electric or hybrid propulsions systems’ growing popularity for use on watercraft. Presented in the paper are design and lab tests of a prototype parallel hybrid propulsion system. It describes a concept of retrofitting a conventionally powered nine meter-long...
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Tribological Properties of Ni-P/Si3N4 Nanocomposite Layers Deposited by Chemical Reduction Method on Aluminum Alloy AW-7075
PublikacjaThe article presents the results of tribological tests of Ni-P/Si3N4 nanocomposite and Ni-P nickel layers deposited on the AW-7075 aluminum alloy by chemical reduction method, and the AW-7075 alloy without coating. Nanocomposite layers were produced using Si3N4 siliconnitride in the form of a polydisperse powder whose particle sizes ranged from 20 to 25 nm. The influence of the content of the dispersion phase layer material on...
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Evaluation of losses in a hydraulic motor based on the SWSB - 63 motor tests
PublikacjaIn this paper are compared two models of energy losses: that suggested by Prof. Paszota,Z. in monograph "Energy losses in the hydraulic displacement motors - definitions and relations serving the evaluation of the efficiency of hydrostatic drive" [18] and that ofProf. Balawender, A. in "Energy analysis and methodology of testing of low-speed hydraulic motors" [1]. By using the data obtained from the tests of SWSB-63 hydraulic motors...
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A Framework of a Ship Domain-based Collision Alert System
PublikacjaThe paper presents a framework of a planned ship collision alert system. The envisaged system is compliant with IMO Resolution MSC.252 (83) “Adoption of the revised performance standards for Integrated Navigation Systems (INS)”. It is based on a ship domain-oriented approach to collision risk and introduces a policy of alerts on dangerous situations. The alerts will include cautions, warnings and alarms, which will be triggered...
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Computational simulation of motion of a rescue module during its launching from ship at rough sea
PublikacjaThis paper is a continuation of the work titled : “A comp utational model for simulation of motion of rescue module during its launching from stern ramp of a ship at rough sea”. It presents results of computer simulations of motion of a rescue module with embarked persons during its launching on rollers along stern ramp of a ship at rough sea. The simulations were conducted for a selected ship fitted with a launching ramp , for...
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Evolutionary Ship Track Planning within Traffic Separation Schemes – Evaluation of Individuals
PublikacjaThe paper presents an extended version of the author’s Evolutionary Sets of Safe Ship Trajectories method. The method plans safe tracks of all ships involved in an encounter including speed reduction manoeuvres, if necessary, and taking into account Rule 10 of COLREGS, which specifies ships’ behaviour within Traffic Separation Schemes governed by IMO. The paper focuses on the evaluation phase of the evolutionary process and shows...
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Solving Multi-Ship Encounter Situations by Evolutionary Sets of Cooperating Trajectories
PublikacjaAutor zaproponował nowe podejście do sytuacji kolizyjnych na morzu. Polega ono na zastąpieniu ewolucyjnej trajektorii własnej ewolucyjnym zbiorem trajektorii wszystkich obiektów. Podejście to umożliwia predykcję manewrowania obiektów obcych przy jednoczesnym zachowaniu efektywności algorytmów ewolucyjnych. Dodatkowo, opracowany już wstępnie przez autorów zbiór kryteriów, ograniczeń i operatorów specjalizowanych powinien zapewnić...
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A numerical model to simulate the motion of a lifesaving module during its launching from the ship’s stern ramp
PublikacjaThe article presents a numerical model of object motion in six degrees of freedom (DoF) which is intended to be used to simulate 3D motion of a lifesaving module during its launching from a ship using a stern ramp in rough sea. The model, of relatively high complexity, takes into account both the motion of the ship on water in changing sea conditions, and the relative motion of the ramp with respect to the ship. The motion of the...
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EVOLUTIONARY MULTI–OBJECTIVE WEATHER ROUTING OF SAILBOATS
PublikacjaThe paper presents a multi-objective method, which optimises the route of a sailboat. The presented method makes use of an evolutionary multi-objective (EMO) algorithm, which performs the optimisation according to three objective functions: total passage time, a sum of all course alterations made during the voyage and the average angle of heel. The last two of the objective functions reflect the navigator’s and passenger’s comfort,...
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Method of determining the degree of liquid aeration in a variable capacity displacement pump
PublikacjaThe Author concludes, that there is a possibility of determining a concrete value of the liquid aeration coefficient during the pump operation by finding such value of coefficient with which the increase of torque of mechanical losses is proportional to the indicated torque determined with a fixed value of increase of pressure in the pump working chambers. The fixed value of increase of pressure assumed in searching the liquid...
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Sailing Vessel Routing Considering Safety Zone and Penalty Time for Altering Course
PublikacjaIn this paper we introduce new model for simulation sea vessel routing. Besides a vessel types (polar diagram) and weather forecast, travel security and the number of maneuvers are considered. Based on these data both the minimal travelling costs and the minimal processing time are found for different vessels and different routes. To test our model the applications SailingAssistance wad improved. The obtained results shows that...
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Method of sum of power losses as a way for determining the ki coefficients of energy losses in hydraulic motor
PublikacjaThis paper shows application of the method of sum of power losses to determining energy losses which occur in hydraulic rotary motor in situation when not all laboratory data are at one’s disposal or when no use is made of data contained in catalogue charts. The method makes it possible to determine the coefficients ,ki , of energy losses occurring in the motor. The method of sum of power losses is based on the approach proposed...
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The catamarans George and Energa Solar
PublikacjaReferat prezentuje unikalne jednostki: George - katamaran zasilany siłą mięśni i Energa Solar - zasilany energią słoneczną.
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Evolutionary Sets of Safe Ship Trajectories: the Method's Development and Selected Reaserch Results
PublikacjaThe 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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A concept of drive and control system of a novel device for people evacuating from large passenger ships
PublikacjaRosnąca z roku na rok liczba oraz wielkość i szybkość pasażerskich statków morskich wymusza szukanie nowatorskich lub doskonalenie dotychczasowych metod bezpiecznej ewakuacji ludzi z tak dużych obiektów. W artykule zaprezentowano koncepcję jednej z takich oryginalnych metod, w której między innymi, zastosowano wyciągi łańcuchowe do utrzymywania na czas rejsu oraz do opuszczania w razie ewakuacji łodzi ratunkowych. Przedstawiono...
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METHOD OF ROUTING SHIPS SAILING IN DEDICATED ENVIRONMENT
PublikacjaThe method for determining the suboptimal route of sailing vessels operating in a restricted area of the sea are proposed in the paper. The dynamics of the environment including weather conditions and speed characteristics of ships sailing are considered. As optimiza-tion criterion, measure sailing time T, and the number of maneuvers performed ω, are taken into account. An heuristic algorithm, and the appropriate application routing...
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EVALUATING THE INFLUENCE OF BENDING STRESS ON A 1H18N9 STEEL SHAFT WEAR PROCESS IN A WATER LUBRICATED SLIDING BEARING WITH A RUBBER BUSHING
PublikacjaThe issue of excessive wear of shaft journals co-working with a rubber bearing has been unexplained so far. Premature and sometimes very intensive wear of ship sliding bearings in water conditions is the reason for carry out very expensive and more frequent than expected repairs. The authors (E. Piątkowska, W. Litwin) made an attempt to find a case that influences the value of this wear described in the paper “Attempt at Evaluating...
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Comparison of the powers of energy losses in a variable capacity displacement pump determined without or with taking into account the power of hydraulic oil compression
PublikacjaPowers of energy losses in a variable capacity displacement pump are compared with or without taking into account the power of hydraulic oil compression. Evaluation of power of liquid compression in the pump was made possible by the use of method, proposed by the Author, of determining the degree of liquid aeration in the pump. In the method of determining the liquid aeration in the pump and of powers of volumetric losses of liquid...
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Energy Loss Coefficients ki in a Displacement Pump and Hydraulic Motor used in Hydrostatic Drives
PublikacjaThe article aims at defining and analysing the energy loss coefficients in design solutions of rotating displacement machines, with a piston machine as an example. The energy losses observed in these machines include mechanical loss, volumetric loss, and pressure loss. The scale and relations between these losses in different machines depend on machine design and manufacturing quality, and on operating parameters. The operating...
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Selected Issues of Hybrid Outboard Motors
PublikacjaThe aim of the research reported in the article was designing a hybrid drive system based on an outboard internal combustion engine offered by a selected producer and testing its operating characteristics. The article presents different designs of this type of drive which can be found in the literature and are available in the market. The designed hybrid outboard drive system was tested both on the laboratory test rig and in real...
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Evolutionary Sets of Safe Ship Trajectories: improving the method by adjusting evolutionary techniques and parameters
PublikacjaThe paper presents some of the evolutionary techniques used by the evolutionary sets of safe ship trajectories method. In general, this method utilizes a customized evolutionary algorithm to solve a constrained optimization problem. This problem is defined as finding a set of cooperating trajectories (here the set is an evolutionary individual) of all the ships involved in the encounter situation. The resulting trajectories are...
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Evolutionary Sets of Safe Ship Trajectories: problem dedicated operators
PublikacjaThe 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...
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A COMPARISON OF WEAR PROPERTIES OF WATER LUBRICATED NBR AND PTFE SLIDING BEARINGS
PublikacjaThe excessive wear of a journal shaft can be caused by many factors, for example, working conditions (e.g., temperaturę, slip speed, the type of lubricant), pressure, the type of material used on the bearings and shafts and their roughness, as well as contamination remaining in the system. This paper presents the roughness profiles co-operating with a rubber (NBR) and polytetrafluoroethylene (PTFE) bushes. The conditions of cooperation...
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Sukces mimo wszystko
PublikacjaAutor jest opiekunem Koła Naukowego Studentów ''KORAB'', działającego przy Wydziale Oceanotechniki i Okrętownictwa Politechniki Gdańskiej. W artykule zaprezentowano katamaran zasilany energią słoneczną, który został zaprojektowany i zbudowany z myślą o starcie w międzynarodowych regatach Frisian Nuon Solar Challenge.W artykule opisano start w regatach, które odbyły się latem 2006r.
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Ramp and chain-lift-launched lifeboats - radical concepts for evacuating cruise ships
PublikacjaW artykule przedstawiono dwie oryginalne koncepcje systemów ewakuacyjnych statków pasażerskich. Pierwsza z nich polega na zastosowaniu otwieranej rampy i pochylni z rolkami, na których umieszczone są w rzędzie łodzie ratunkowe, zaczepione do elementów wyciągu łańcuchowego. Druga koncepcja polega na umieszczeniu łodzi, jedna nad drugą, na wyciągu łańcuchowym. W obu systemach w trakcie ewakuacji łodzie opuszczane są grawitacyjnie...
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Wybrane problemy nawijania lin i kablolin na bębnach wciągarek
PublikacjaW referacie przedstawiono kilka wybranych problemów związanych z wielowarstwowym nawijaniem lin oraz kablolin na bębnach wciągarek. Pokazano przy tym fotografie dwóch przykładowych wciągarek, w których problemy te wystąpiły.
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Brawo, GEORGE!
PublikacjaAutor jest opiekunem Koła Naukowego Studentów ''KORAB'', działającego przy Wydziale Oceanotechniki i Okrętownictwa Politechniki Gdańskiej. W artykule zaprezentowano nowozbudowany katamaran GEORGE napędzany siłą ludzkich mięśni, zaprojektowany i zbudowany z myślą o starcie w międzynarodowych regatach International Waterbike Regatta Istambuł 2006. Tekst zawiera relację z regat w których studenci Politechniki Gdańskiej odnieśli zwycięstwo.
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Bezpieczna ewakuacja ludzi ze statków - prace realizowane w ramach Europejskiego Projektu Badawczego SAFECRAFTS
PublikacjaPrzedstawiony referat ma na celu zapoznanie środowiska okrętowców z zakresem prac badawczych, prowadzonych w ramach Europejskiego Projektu 6 Programu Ramowego pod nazwą ''Safecrafts - bezpieczna ewakuacja ludzi ze statków''.
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Projektowanie wiedzy. Relacyjne bazy danych (ISBN 978-83-7348-702-4)
PublikacjaZałożeniem podręcznika Projektowanie wiedzy – relacyjne bazy danych jest kształtowanie praktycznych umiejętności opartych na wiedzy z zakresu tworzenia relacyjnych baz danych z wykorzystaniem narzędzi Microsoft Access. Książka zawiera zestawy ćwiczeń i zadań wraz z rozwiązaniami, które umożliwiają skuteczną naukę prawidłowego tworzenia modelu danych. Opracowanie wyróżnia się na tle innych prac bardzo szczegółowym i dokładnym...
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Wyznaczanie parametrów ruchu łodzi ratowniczej opuszczanej ze statku na fali
PublikacjaW pracy przedstawiono model obliczeniowy oraz różniczkowe równania ruchu łodzi ratowniczej, opuszczanej z pokładu statku kołyszącego się na fali.