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Year 2019
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Analysis of the macrostructure of the fuel spray atomized with marine engine injector
PublicationOne of the main problem influencing the combustion process in the cylinder of the marine engine is an fuel spray phenomena. The parameters describing the shape of the fuel spray are named macro parameters. This article presents the research results of the macrostructure parameters of the fuel spray atomized with the marine engine injector. The research were carried out by optical visualization measurement method of Mie scattering....
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ANALYSIS OF THE PROJECT OF INNOVATIVE FLOATING TURBINE
PublicationThe design of a floating, innovative device for river water aeration and conversion of mechanical energy to electrical energy required the analysis of a number of geometrical and dynamic features. Such an analysis may be carried out on the basis of existing methods of numerical fluid mechanics. Models of pressures, forces and torques characteristic for the conversion of watercourse energy were developed for two basic concepts of...
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APPLICABILITY OF INLET AIR FOGGING TO MARINE GAS TURBINE
PublicationThe dependency of marine gas turbine on the ambient temperature leads to a decrease of the gas turbine power output in arid areas. Very often gas turbine power output demand is high and the power margins originally designed into the driver , has been exhausted. In such circumstances the inlet air fogging is an effective compensation of gas turbine power. In this paper an analysis of inlet air fogging applicability to marine gas...
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Application of Intuitionistic Fuzzy Sets to the assessment of technical university students
PublicationThe article proposes application of artificial intelligence methods to assess students of technical universities. The level of achieved educational goals can be assessed using measurements based on the idea of Fuzzy Intuitionistic Sets (IFS). A classification algorithm was developed and an exemplary distribution of the criteria values using IFS was presented. The application of the proposed approach in online education can enrich...
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Application of the Optimization Methods to the Search of Marine Propulsion Shafting Global Equilibrium in Running Condition
PublicationFull film hydrodynamic lubrication of marine propulsion shafting journal bearings in running condition is discussed. Considerable computational difficulties in non-linear determining the quasi-static equilibrium of the shafting are highlighted. The approach using two optimization methods (the particle swarm method and the interior point method) in combination with the specially developed relaxation technique is proposed to overcome...
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Application of Thermo-chemical Technologies for Conversion of Associated Gas in Diesel-Gas Turbine Installations for Oil and Gas Floating Units
PublicationThe paper considers the issue of thermo-chemical recovery of engine’s waste heat and its further use for steam conversion of the associated gas for oil and gas floating units. The characteristics of the associated gas are presented, and problems of its application in dual-fuel medium-speed internal combustion engines are discussed. Various variants of combined diesel-gas turbine power plant with thermo-chemical heat recovery are...
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Assessment of the Environmental Impact of a Car Tire throughout Its Lifecycle Using the LCA Method
PublicationThere are numerous threats to the natural environment that pose a significant risk both to the environment and to human health, including car tires. Thus, there is a need to determine the impact of the life cycle of car tires on the environment, starting with the processes of raw materials acquisition, production, and ending with end-of-life management. Therefore, the authors of this study chose to do research on passenger car...
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BADANIA PILOTAŻOWE DRGAŃ NA WLOCIE DO SPRĘŻARKI TURBINY GAZOWEJ GTD 350
PublicationPodstawą diagnostyki maszyn wirnikowych są pomiary drgań ze względu na to że prawie wszystkie uszkodzenia maszyn powodują istotne zmiany wielkości je opisujących np. prędkości drgań. W eksploatacji maszyn wirnikowych najważniejsza jest ocena drgań obiektu na podstawie pomiarów wykonywanych na częściach niewirujących. Badania, których wyniki przedstawiono w referacie zostały przeprowadzone na stanowisku...
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Debonding Detection in Reinforced Concrete Beams with the Use of Guided Wave Propagation
PublicationOne of the most frequent damage of the reinforced concrete structures is debonding between steel bar and concrete cover. In the case of debonding occurrence not only the strength of the structure decreases, but also it is more vulnerable to corrosion damages. For this reason fast and effective methods of debonding detection in an early stage of its development need a significant boost. The paper presents analytical and experimental...
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Design of Jack-up Platform for 6 MW Wind Turbine: Parametric Analysis Based Dimensioning of Platform Legs
PublicationThe article presents the results of the research conducted within the framework of the project entitled WIND-TU-PLA (ERA-NET, MARTEC II), the general aim of which was to design and analyse supporting structures for wind turbines intended for operation on the South Baltic area. The research part described in the article aimed at developing a preliminary design for a jack-up platform which can operate on water areas with depth of...
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Energy Demand of Short-Range Inland Ferry with Series Hybrid Propulsion Depending on the Navigation Strategy
PublicationInterest 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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ENERGY EFFICIENT SMALL INLAND PASSENGER SHUTTLE FERRY WITH HYBRID PROPULSION - CONCEPT DESIGN, CALCULATIONS AND MODEL TESTS
PublicationIn 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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Energy Loss Coefficients ki in a Displacement Pump and Hydraulic Motor used in Hydrostatic Drives
PublicationThe 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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Experimental research on marine oil-lubricated stern tube bearing
PublicationBearings 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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Experimental Research on the Energy Efficiency of a Parallel Hybrid Drive for an Inland Ship
PublicationThe 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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FE analysis of support-specimen interaction of compressive experimental test
PublicationThe objective of this work is to investigate the support-specimen interaction during the compressive experimental testing of stiffened plates. The interaction is analyzed employing the nonlinear Finite Element Method using the commercial software ANSYS. The connection between the stiffened plate and testing supports is modelled with the use of contact elements, where several possible interaction scenarios are investigated, and...
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Finding safe and efficient shipping routes in ice-covered waters: A framework and a model
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Framework of an Evolutionary Multi-Objective Optimisation Method for Planning a Safe Trajectory for a Marine Autonomous Surface Ship
PublicationThis 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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Full scale CFD seakeeping simulations for case study ship redesigned from V-shaped bulbous bow to X-bow hull form
PublicationIncreasing propulsion efficiency, safety, comfort and operability are of the great importance, especially for small ships operating on windy sites like the North Sea and the Baltic Sea. Seakeeping performance of ships and offshore structures can be analysed by different methods and the one that is becoming increasingly important is CFD RANS. The recent development of simulation techniques together with rising HPC accessibility...
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Full-scale CFD simulations for the determination of ship resistance as a rational, alternative method to towing tank experiments
PublicationResults of ship resistance predictions obtained from towing tank experiments are affected by the method used to extrapolate from a model scale to a ship scale. Selection of method to determine a form factor is subjective and the extrapolation method is accurate for typical hull forms. For innovative hull forms the proper method for calculating the form factor is questionable. Moreover, the influence of the extrapolation method...
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Guided Wave Propagation in Detection of Partial Circumferential Debonding in Concrete Structures
PublicationThe following article presents results of investigating the damage detection in reinforced concrete beams with artificially introduced debonding between the rod and cover, using a non-destructive method based on elastic waves propagation. The primary aim of the research was to analyze the possible use of guided waves in partial circumferential debonding detection. Guided waves were excited and registered in reinforced concrete...
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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
PublicationThis 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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Hydrodynamic Loads on Marine Propellers Subject to Ventilation and Out of Water Condition
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Identification of damages in the inlet air duct of a diesel engine based on exhaust gas temperature measurements
PublicationThe temperature of the exhaust gas of a diesel piston engine, measured in the characteristic control sections of its thermo-flow system, can be a valuable source of diagnostic information about the technical condition of the elements limiting the working spaces thus separated, including the turbocharging system, but also its fuel supply system and replacement of the medium. In standard marine engine measurement systems equipped...
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Improvement of ships seakeeping performance by application of the Full-scale CFD simulations – case study
PublicationThe ship’s fuel economy is increasingly important. The paper presents the effect of redesigning a case study ship for increasing seakeeping performance. Selected wave parameters reflects very difficult operational con-ditions existing on the North Sea and the Baltic Sea. The analyzed variants of a case study ship represent the latest developments of modern hull forms. The concepts similar to V-shaped bulbous bow, X-bow, X-aft,...
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Investigation of the Combustion Processes in the Gas Turbine Module of an FPSO Operating on Associated Gas Conversion Products
PublicationIn this paper, we consider the issue of thermo-chemical heat recovery of waste heat from gas turbine engines for the steam conversion of associated gas for offshore vessels. Current trends in the development of offshore infrastructure are identified, and the composition of power plants for mobile offshore drilling units and FPSO vessels is analyzed. We present the results of a comparison of power-to-volume ratio, power-to-weight...
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Investigation of the thermal effects in water-lubricated journal bearings with axial grooves
PublicationWater-lubricated hydrodynamic journal bearings are frequently applied as stern tube bearings due to their advantages over other bearing types. They are environmentally friendly, can operate without sealings and in conditions of low friction losses. The most popular are bearings with open axial grooves, which require, for proper operation, forced axial flow of the lubricating water. Correctly designed and operated stern tube bearings...
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Jaw biomechanics: Estimation of activity of muscles acting at the temporomandibular joint
PublicationThe aim of this study was to elaborate a method of estimation of activity of surface muscles acting at the temporomandibular joint of the healthy subjects by using a surface electromyography (EMG). The scope of this study involved testing chosen jaw motions (open, close, lateral deviation) and process of mastication occurring during eating food with different toughness (chewing gum, cereal and carrot) by using mixed sides, right...
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Justification of models of changing project environment for harvesting grain, oilseed and legume crops
PublicationAn analysis of the condition of implementation of projects in agricultural production is carried out. The disadvantages of existing methods and models of planning of the content and time of execution of works in the projects, which mostly do not take into account the changing components of their project environment, are substantiated. The proposed methodology for justifying the models of a changing project environment for harvesting...
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Marine propeller shaft bearings under low-speed conditions: water vs. oil lubrication
PublicationThe 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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METODA POŚREDNIEGO WYZNACZANIA MOCY EFEKTYWNEJ WOLNOOBROTOWEGO SILNIKA OKRĘTOWEGO NA PODSTAWIE EKSPLOATACYJNYCH POMIARÓW CIŚNIENIA POWIETRZA DOŁADOWUJĄCEGO
PublicationW artykule przedstawionometodę, która pozwala w przybliżony sposób wyznaczyć względną moc okrętowego silnika głównego w warunkach eksploatacji na podstawie standardowego pomiaru ciśnienia powietrza doładowującego wkanaledolotowym. Metoda oparta jest na określaniuwspółczynnikówaproksymującej funkcji liniowej, przy znanym ciśnieniu doładowania oraz rodzaju i mocy nominalnejsilnika.Jest ona uzupełnieniem innych metodpośredniego...
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METODY IDENTYFIKACJI STANÓW NIEZDATNOŚCI EKSPLOATACYJNEJ OKRĘTOWYCH WAŁÓW NAPĘDOWYCH – POMIARY DRGAŃ MECHANICZNYCH LINII WAŁÓW
PublicationAnalizując eksploatacyjne przyczyny utraty współosiowości linii okrętowych wałów napędowych należy zauważyć, że jedynie systematyczna kontrola wzajemnego posadowienia elementów linii napędowej (silnika, linii wałów pośrednich i wału śrubowego) prowadzi do zwiększenia niezawodności okrętowego układu napędowego. Wstępnej oceny stanu współosiowości linii wałów okrętowych, w zakresie ich przesunięcia i załamania dokonuje się podczas...
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Model Predictive Super-Twisting Sliding Mode Control for An Autonomous Surface Vehicle
PublicationThis 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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Modelling and Measurement of Folk Guitar: Truss Rod and Strings in Numerical Analysis of Tone
PublicationThe study makes an attempt to model a complete vibrating guitar including its non-linear features, specifically the tension-compression of truss rod and tension of strings. The purpose of such a model is to examine the influence of design parameters on tone. Most experimental studies are flawed by uncertainties introduced by materials and assembly of an instrument. Since numerical modelling of instruments allows for deterministic...
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Modelowanie procesów energetycznych w obrotowym układzie mechanicznym dla potrzeb diagnozowania zmęczenia okrętowych wałów napędowych
PublicationW rozprawie podjęto problematykę energetycznych skutków pękania zmęczeniowego okrętowych wałów napędowych w kontekście ich diagnozowania. Dokonano parametrycznej i konstrukcyjnej klasyfikacji okrętowych układów napędowych z zawężeniem obszaru typów okrętów najbardziej podatnych na pęknięcia zmęczeniowe wałów okrętowych. Przeprowadzono badania modelowe na stanowisku wytrzymałościowym odzwierciedlającym pracę okrętowej linii napędowej...
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MODERNIZACJA STANOWISKA DO BADANIA WTRYSKIWACZY W WARUNKACH ZASILANIA SILNIKA PALIWAMI MODYFIKOWANYMI
PublicationArtykuł przedstawia tematykę stanowiącą kontynuację podjętej przez zespół badawczy Katedry Siłowni Morskich i Lądowych Wydziału Oceanotechniki i Okrętownictwa Politechniki Gdańskiej problematyki oceny charakterystyk przepływowych wtryskiwaczy zasilanych modyfikowanymi paliwami żeglugowymi w skrajnie różnych warunkach otoczenia. Przeprowadzone na prototypowym stanowisku badania pilotażowe [8, 9] pozwoliły na doprecyzowanie założeń...
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MOŻLIWOŚCI WYKORZYSTANIA METOD I MODELI PROBABILISTYCZNYCH W PROJEKTOWANIU OKRĘTOWYCH INSTALACJI PAROWYCH
PublicationArtykuł przedstawia możliwości wykorzystania metod i modeli probabilistycznych w projektowaniu okrętowych instalacji parowych w siłowniach spalinowych. Zaproponowano dwie możliwości opisu eksploatacyjnych wydajności kotłów utylizacyjnych oraz eksploatacyjnego zapotrzebowania ciepła. Pierwsza to zastosowanie do opisu rozkładu normalnego, drugą jest zamodelowanie okrętowej instalacji parowej jako systemu masowej...
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NEW CONCEPT OF HYBRID PROPULSION WITH HYDROSTATIC GEAR FOR INLAND WATER TRANSPORT
PublicationThe 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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Niekonwencjonalne metody odzysku ciepła odpadowego na statkach
PublicationW artykule opisano kilka metod odzysku ciepła odpadowego, które nie znalazły jeszcze szerokiego zastosowania na statkach. Obecnie, powszechnie wykorzystuje się ciepło spalin do wytwarzania pary wodnej grzewczej, a ciepło wody chłodzącej cylindry silników głównych - do wytwarzania wody słodkiej w wyparownikach podciśnieniowych. Znacznie rzadziej, para wodna lub spaliny służą do napędu turbogeneratorów. Metody te są jednak wykorzystywane...
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Numerical investigation of the core eccentricity effect on wave propagation in embedded waveguide
PublicationThe paper presents results of theoretical and numerical investigation of guided wave propagation in two-layer bars with geometric imperfections in the form of eccentric location of steel core. Steel rod of diameter equal to 1 cm embedded in composite mortar-type cover with external diameter equal to 5 cm has been taken into consideration. Several different rods with variable size of eccentricity are analysed. Results for rods with...
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Numerical modeling and experimental validation of full-scale segment to support design of novel GFRP footbridge
PublicationThe paper contains analysis of full-scaled three meters long segment of a novel composite footbridge. Both numerical modeling and experimental validation were performed. Analyzed object is a shell type sandwich channel-like structure made of composite sandwich with GFRP laminates as a skin and PET foam as a core. Several static load schemes were performed including vertical and horizontal forces. In FEM analysis multilayered laminate...
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Ocena emisyjności i środowiskowego bezpieczeństwa napędu rozdrabniaczy biomasy
PublicationOpracowano model matematyczny emisyjności napędu rozdrabniania biomasy wykorzystywanej energetycznie. Wykazano, że możliwe jest utworzenie modelu uwzględniającego środowiskowe bezpieczeństwo eksploatacji i zastosowanie go do analizy, oceny i rozwoju napędu rozdrabniaczy biomasy energetycznej. Określono też jak zmienne sterujące maszyny rozdrabniającej wpływają na bilans i ocenę ekologiczną procesu. Opracowano również autorski wskaźnik...
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POSZUKIWANIE RELACJI DIAGNOSTYCZNYCH POMIĘDZY USZKODZENIAMI W KANALE SPALIN WYLOTOWYCH SILNIKA O ZS A SZYBKOZMIENNĄ TEMPERATURĄ SPALIN
PublicationTemperatura spalin wylotowych tłokowego silnika spalinowego o zapłonie samoczynnym, mierzona w charakterystycznych przekrojach kontrolnych jego układu cieplno-przepływowego, może stanowić cenne źródło informacji diagnostycznej o stanie technicznym elementów ograniczających wydzielone w ten sposób przestrzenie robocze, wraz z układem turbodoładowania, ale także jego układu zasilania paliwem i wymiany czynnika roboczego. W standardowych...
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Prediction of ship resistance with the use of Full-scale CFD simulations
PublicationIn recent years, the IMO has introduced new regulations to reduce the negative impact of ships on the natural environment. A particularly important step forcing technological innovations is the increasing requirement of ship energy efficiency. It is expressed by the Energy Efficiency Design Index (EEDI). Another important step towards green shipping is rising the required quality of fuel used for propulsion, so called Tier limits....
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Preference-based evolutionary multi-objective optimization in ship weather routing
PublicationIn 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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Preliminary Results of a System-theoretic Assessment of Maritime Autonomous Surface Ships' Safety
PublicationWhile a system‐theoretic approach to the safety analysis of innovative socio‐technical systems gains a growing acceptance among academia, safety issues of Maritime Autonomous Surface Ships (MASS) remain largely unexplored. Therefore, we applied a System‐Theoretic Process Analysis to develop and analyze a preliminary model of the unmanned shipping system in order to elaborate safety recommendations for...
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PRZEGLĄD DZIAŁALNOŚCI NAUKOWO-DYDAKTYCZNEJ KATEDRY SIŁOWNI MORSKICH I LĄDOWYCH WYDZIAŁU OCEANOTECHNIKI I OKRĘTOWNICTWA POLITECHNIKI GDAŃSKIEJ
PublicationW artykule zaprezentowanoprofil statutowej działalnościKatedry Siłowni Morskich i Lądowych Wydziału Oceanotechniki i Okrętownictwa Politechniki Gdańskiejw zakresie badań naukowych oraz dydaktyki. Przybliżono, specyfikę funkcjonowania Katedry, którątradycyjnie charakteryzują bliskiezwiązkiz marynarką wojenną(początkowo niemiecką, a następnie polską), dla której zawsze stanowiła ważnezapleczeintelektualne...
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Reference-free determination of debonding length in reinforced concrete beams using guided wave propagation
PublicationThis paper presents theoretical and experimental investigations of guided wave propagation in reinforced concrete beams, with pre-existing debonding between steel rebars and concrete blocks, for the purpose of damage detection. The primary aim of these investigations was a detailed analysis of the possible applications of wave propagation in single and multiple debonding detection in reinforced concrete structures and reference-free...
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REVIEW OF WEATHER FORECAST SERVICES FOR SHIP ROUTING PURPOSES
PublicationWeather 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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Rewizja przybliżonej metody szacowania oporu całkowitego kadłuba płynącego w przechyle
PublicationNa tle innych obiektów pływających jacht żaglowy wyróżnia się m.in. tym, że choć jest zaprojektowany jako pojazd poruszający się w pozycji wyprostowanej, to jednak znaczną część czasu żegluje w przechyle. Dlatego tak ważne jest poznanie zachodzących wtedy zjawisk, zwłaszcza związanych z oporem hydrodynamicznym. W artykule zaprezentowano porównanie oparte na weryfikacji wybranej, przybliżonej metody oszacowania zmian oporu całkowitego...