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Search results for: ship-wave interaction
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Investigating the current environmental situation in the Middle East and North Africa (MENA) region during the third wave of COVID-19 pandemic: urban vs. rural context
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Evolutionary sets of cooperating ship trajectories: open waters and restricted waters = Ewolucyjne zbiory współpracujących trajektorii statków: wody otwarte i wody ograniczone
PublicationW artykule przedstawiono nową metodę rozwiązywania sytuacji spotkań wielu statków na wodach otwartych i wodach ograniczonych. Metoda łączy niektóre z elementów podejścia opartego na teorii gier z programowaniem ewolucyjnym i szuka optymalnego zbioru bezpiecznych trajektorii wszystkich statków zaangażowanych w potencjalną sytuację kolizyjną. Pozwala ona nawigatorowi przewidzieć najbardziej prawdopodobne zachowanie statków obcych...
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Research on heavy loaded water lubricated main shaft bearings of the ship = Badania mocno obciążonych, smarowanych wodą łożysk wału śrubowego jednostki pływającej
PublicationW referacie zaprezentowano wyniki badań łożyska z polimerową panwią smarowanego wodą, jednego z wiodących producentów. Próby prowadzono dla dwóch odmiennych warunków pracy: dla typowych wielkości obciążeń, jakie występują w łożysku rufowym okrętowego wału głównego oraz dla obciążeń, przy których średnie naciski są bliskie wartościom dopuszczalnym, określonym przez producenta. Przeprowadzone badania wykazały, że łożysko pracuje...
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Modelling of Ship’s Heeling and Rolling for the Purpose of Gantry Control Improvement in the Course of Cargo Handling Operations in Sea Ports
PublicationThe paper presents two proposals of models of interaction between a ship and cargo being loaded or discharged by a gantry in port, in terms of heeling and rolling of the vessel. The main purpose of such modelling is the need for improvement of gantry control with regard to faster operations thanks to more accurate estimation of level and moment of cargo release from a gantry hook or spreader. The study may be the contribution to...
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Structure-activity relationship study of a small cyclic peptide H-c[Lys-Pro-Glu]-Arg-OH: a potent inhibitor of Vascular Endothelial Growth Factor interaction with Neuropilin-1
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Wave energy attenuation in fields of colliding ice floes – Part 1: Discrete-element modelling of dissipation due to ice–water drag
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Brain-computer interaction based on EEG signal and gaze-tracking information = Analiza interackji mózg-komputer wykorzystująca sygnał EEg i informacje z systemu śledzenia punktu fiksacji wzroku
PublicationThe article presents an attempt to integrate EEG signal analysis with information about human visual activities, i.e. gaze fixation point. The results from gaze-tracking-based measurement were combined with the standard EEG analysis. A search for correlation between the brain activity and the region of the screen observed by the user was performed. The preliminary stage of the study consists in electrooculography (EOG) signal processing....
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Lower rim substituted p-tert-butyl-calix[4]arene. Part 16. Synthesis of 25,26,27,28-tetrakis(piperidinylthiocarbonylmethylene)-p-tert-butylcalix[4]arene and its interaction with metal ions
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Interaction of amphotericin B and its low toxic derivative, N-methyl-N-D-fructosyl amphotericin B methyl ester, with fungal, mammalian and bacterial cells measured by the energy transfer method.
PublicationPochodna amfoterycyny B ( AMB) ester metylowy N-metylo-N-D-fruktozylo amfoterycyny B (MFAME) wykazuje szerokie spektrum i wysoką aktywność przeciwgrzybową wyjściowego amtybiotyku i równocześnie toksyczność mniejszą o dwa rzędy wielkości. Celem tej pracy było ustalenie czy obserwowane różnice między toksycznością pochodnej i wyjściowego antybiotyku wynikają z różnic w powinowactwie do błon komórkowych grzybów i komórek ssakowych....
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Ocena zasobów eksploatacyjnych w warunkach intensywnego współdziałania ujęć w rejonie Trójmiasta = The admissible volume of extracted groundwater under conditions of intensive interaction between groundwater intakes in Tricity region
PublicationAglomeracja Trójmiejska położona jest na bardzo zróżnicowanym geomorfologicznie obszarze. Wody podziemne ujmowane są zarówno na obszarze wysoczyzny - w strefie zasilania i przepływu wód podziemnych, jak i na obszarze nizin nadmorskich - w strefie ich drenażu. W artykule przestawiono wyniki badań modelowych prowadzonych w celu ustalenia zasobów eksploatacyjnych wód z utworów czwartorzędowych na jednym z ujęć zlokalizowanych w...
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On the possible increasing of efficiency of ship power plant with the system combined of marine diesel engine, gas turbine and steam turbine at the main engine - steam turbine mode of cooperation
PublicationW pracy przedstawiono koncepcję układu kombinowanego okrętowego dużej mocy złożonego z silnika głównego tłokowego oraz skojarzonych z nim turbiny gazowej mocy i układu turbiny parowej, wykorzystujących energię zawartą w spalinach wylotowych silnika głównego tłokowego. Rozpatrywano układ kombinowany układ złożony z silnika spalinowego tłokowego skojarzony z układem turbiny parowej. Podano algorytm i obliczenia poszczególnych podukładów:...
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Possible use of combined diesel engine/steam turbine in ship power plant = Możliwości zastosowania układów kombinowanych: silnik diesla - turbina parowa w siłowniach okrętowych
PublicationW artykule przedstawiono układ kombinowany dużej mocy. Składa się on z silnika spalinowego tłokowego oraz skojarzone z nim układu turbiny parowej, wykorzystującego energię spalin wylotowych. Rozpatrzono tylko wariant silnik Diesla - turbina parowa, z kotłem utylizacyjnym jednociśnieniowym. Podano założenia i ograniczenia oraz wyniki obliczeń z opracowanego programu komputerowego. Obliczenia numeryczne wykonano dla silników spalinowych...
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Simple Physics-Based Analytical Formulas for the Potentials of Mean Force for the Interaction of Amino Acid Side Chains in Water. 3. Calculation and Parameterization of the Potentials of Mean Force of Pairs of Identical Hydrophobic Side Chains
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Priorities in the risk assessment and risk management during the ship accident at sea /Priorytety w ocenie ryzyka i zarządzaniu ryzykiem w czasie katastrofy statku na morzu
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Driving a new perspective Professor Zygmunt Paszota, faculty of ocean engineering and ship technology, Gdansk University of Technology, Poland, explains a new approach to the Sankey Diagram for drive motors
PublicationThe paper presents the necessity of replacing the traditional, commonly accepted but erroneous, Sankey diagram of power decrease in the direction of power flow by the diagram, proposed by the Author, of power increase in the direction opposite to the direction of power flow. The proposed view of losses and energy efficiency should be applied to all types of drive motors and drive systems. The presented proposals open a new perspective...
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Instantaneous Heating and Cooling Caused by Periodic or Aperiodic Sound of Any Characteristic Duration in a Gas with Vibrational Relaxation
PublicationThermodynamic relaxation of internal degrees of a molecule's freedom in a gas occurs with some characteristic time. This makes wave processes in a gas behave differently depending on the ratio of characteristic duration of perturbations and the relaxation time. In particular, generation of the secondary non-wave modes by intense sound in a nonlinear flow dependens on frequency. These kinds of interaction are considered in this...
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Uwagi o problemach w nauczaniu projektowania i eksploatacji siłowni okrętowych (referat dyskusyjny) = Remarks on problems in teaching about designing and operating in ship power plant (discursive study).
PublicationW referacie uzasadniono celowość uwzględniania wybranych zagadnień projektowania siłowni w kształceniu studentów wydziałów mechanicznych akademii morskich i zagadnień eksploatacji siłowni w kształceniu studentów odpowiednich wydziałów politechnik.
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Lower Rim Substituted p-tert-Butyl-Calix[4]arene. Part 16. Synthesis of 25, 26, 27, 28-tetrakis(piperidinethiocarbonylmethylene)-p-tert-butylcalix[4]arene and its interaction with metal ions
PublicationThe synthesis, characterisation and X-ray crystal structures of p-tert-butyl-calix[4]arenethioamide L and its complex with lead L-Pb2+ is reported. The cation-binding properties in solution have been assessed by liquid-liquid extraction of the metal picrates from water into dichloromethane and by stability constants determination in acetonitrile using UV-absorption spectrophotometry or potentiometry. The compound was used as active...
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Detection of Objects Buried in the Sea Bottom with the Use of Parametric Echosounder
PublicationThe paper contains results of a in situ research main task of which was to detect objects buried, partially or completely, in the sea bottom. Object detecting technologies employing acoustic wave sources based on nonlinear interaction of elastic waves require application of parametric sound sources. Detection of objects buried in the sea bottom with the use of classic hydroacoustic devices such as the sidescan sonar or multibeam...
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Numeryczna analiza wpływu kierunku rozchodzenia się fali wybuchu na krzywiznę asymetrycznie walcowanego pasma Al-Cu. Numerical analysis the influence of the direction of explosion wave at the curvature of asymmetrical rolling of bimetallic plate.
PublicationW artykule przedstawiono numeryczną analizę wpływu kierunku rozchodzenia się fali wybuchu na krzywiznę asymetrycznie walcowanego pasma Al-Cu. Przeprowadzono symulacje dla procesu walcowania w temperaturze 20 C. Proces walcowania prowadzono w walcarce duo D 150 mm, o prędkości obwodowej 18,5 obr/min. Badania przeprowadzono dla dwóch stosunków grubości warstw 2/10 i 4/8. Symulację procesu przeprowadzono dla trzech gniotów 10%, 20%,...
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On the possible increasing of efficiency of ship power plant with the system combined of marine diesel engine, gas turbine and steam turbine in case of main engine cooperation with the gas turbine fed in parallel and the steam turbine
PublicationW pracy przedstawiono koncepcję układu kombinowanego okrętowego dużej mocy złożonego z wiodącego silnika głównego spalinowego silnika tłokowego i skojarzonych z nim turbiny gazowej mocy i układu turbiny parowej, wykorzystujących energię zawartą w spalinach wylotowych głównego silnika spalinowego. Rozpatrzono wariant układu kombinowanego, w którym główny jest silnik tłokowy skojarzony z turbiną gazową mocy i układem turbiny parowej,...
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On the possible increasing of efficiency of ship power plant with the system combined of marine diesel engine, gas turbine and steam turbine in case of main engine cooperation with the gas turbine fed in series and the steam turbine
PublicationW pracy przedstawiono koncepcję układu kombinowanego okrętowego dużej mocy złożonego z wiodącego silnika głównego silnika spalinowego tłokowego oraz skojarzonych z nim turbiny gazowej mocy i układu turbiny parowej, wykorzystujących energię zawartą w spalinach wylotowych silnika spalinowego. Rozpatrywano wariant układu kombinowanego, którym turbina mocy jest zasilana szeregowo spalinami wylotowymi. Podano algorytm i obliczenia...
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An asymmetrical λ-foot of condensing steam flow in the IMP PAN nozzle
PublicationIn the present paper we have focused on the precise prediction of the spontaneous condensation phenomena in wet steam flow. Novelty of our approach lies on modelling both the moment of initiation of a phase transition, as well as the moment of its reverse progress - called here re-vaporization of the condensate phase. The practical issue is to elaborate of a model of spontaneous condensation/vaporization of water steam flow...
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Move into the open space – what can we expect from moving artistic interventions to open urban spaces?
PublicationThe paper discuses the role of incorporating creative engagement into the processes of urban and social development using cultural means of action and expression and the potential of artistic interventions in public space. The block of initiatives within the People’s Smart Sculpture EU project, realized by Gdańsk City Gallery, has been named “Move Into The Open Space”. This paper will provide...
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FDTD Simulations on Disjoint Domains with the Use of Discrete Green's Function Diakoptics
PublicationA discrete Green's function (DGF) approach to couple disjoint domains in the finite-difference time-domain (FDTD) grid is developed. In this method, total-field/scattered-field (TFSF) FDTD domains are associated with simulated objects whereas the interaction between them is modeled with the use of the DGF propagator. Hence, source and scatterer are simulated in separate domains and updating of vacuum cells, being of little interest,...
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Model of ship's magnetic signature
PublicationShips 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...
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Multidipoles model of ship's magnetic field
PublicationShips 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...
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Multidipoles model of ship's magnetic field
PublicationShips 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...
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Wnikanie wodoru z paliwa i oleju do stali stopowych 26h2mf i 34hnm oraz jego oddziaływanie z defektami struktury = The hydrogen entry from fuel and oil to the 26h2mf and 34hnm alloy steels, and its interaction with structure defects
PublicationWykonano badania skłonności do korozji naprężeniowej przy rozciąganiu próbek ze stałą małą prędkością 10-6s-1, przy obciążeniu cyklicznie zmiennym w środowisku gorącego paliwa kotłowego i gliceryny oraz badania absorpcji wodoru dla stali stopowych 26H2MF i 34HNM w paliwie kotłowym, przepracowanym oleju mineralnym oraz glicerynie jako środowisku referencyjnym. Wykazano największą wrażliwość stali przy obciążeniach zmiennych oraz...
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A modified static equivalency method for roll-on/roll-off vessels
PublicationPrzedstawiono zmodyfikowaną metodę statycznej równoważności dla statków ro-ro, opartą na wypiętrzaniu się wody na pokładzie samochodowym w wypadku wystąpienia otworu w burcie, do oceny bezpieczeństwa statku.
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Ship’s de-perming process using coils lying on seabed
PublicationA ship built from ferromagnetic steel disturbs the uniformity of the Earth’s magnetic field. Changes of ship’s signature are due to the magneto-mechanical interaction of the hull with the Earth’s magnetic field. The ship’s magnetic field can be detected by a magnetic naval mine. For this reason, the vessel has to be demagnetized. There are several methods of ship’s de-perming. The results of experimental and computer simulations...
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Designing Particle Kalman Filter for Dynamic Positioning
PublicationThe article presents a comparative analysis of two variants of the Particle Kalman Filter designed by using two different ship motion models. The first filter bases only on the kinematic model of the ship and can be used in many types of vehicles, regardless of the vehicle dynamics model. The input value to the filter is the noisy position of the ship. The second filter makes use of the kinematic and dynamic models of the moving...
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On the Nonlinear Effects of Magnetoacoustic Perturbations in Optically Thin Quasi-Isentropic Plasmas
PublicationNonlinear effects of planar magnetosound perturbations in a plasma are discussed. Plasma is non-adiabatic due to optically thin radiation and external heating. For these reasons, thermal instability of a plasma may appear which makes it acoustically active. The plasma is assumed to be initially homogeneous ideal gas with infinite electrical conductivity permeated by a straight magnetic field which is orthogonal to the trajectories...
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Identification of ship’s hull mathematical model with numerical methods
PublicationThe modern maritime industry is moving toward the development of technology that will allow for full or partial autonomy of ship operation. This innovation places high demands on ship performance prediction techniques at the design stage. The researchwork presented in the article is related to the design stage of the ship and concerns methods for prognosis and evaluation of the specific operational condition of the ship, namely...
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Modelling Of Commercial Websites. A New Perspective On Usability And Customer Relation
PublicationFrom an economic point of view, a critical aspect of online services is their ability to retain customers. The aim of presented study was the use of a layered model VIPR (Visual - Interaction - Process - Relation ) for commercial services online. The indicator of trust and establishing lasting relationships were assessment achieved from experienced users of commercial online services (n = 207), obtained by means of Web Credibility...
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Directed electromagnetic pulse dynamics: projecting operators method
PublicationIn this article, we consider a one-dimensional model of electromagnetic pulse propagation in isotropic media, takinginto account a nonlinearity of the third order. We introduce a method for Maxwell's equation transformation on thebasis of a complete set of projecting operators. The operators correspond to wave dispersion branches including thedirection of propagation. As the simplest result of applying the method, we derive a system...
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Towards a method for detecting large roll motions suitable for oceangoing ships
PublicationThe concept of autonomous merchant ships is quite recent. The increasing interest in autonomous vessels is nowadays calling for smart technologies that are supposed to replace the human actions on board. This involves troublesome issues related to ship safety. In the future, decision-making processes that are conventionally performed by human beings on board ship will be moved ashore to the control centre and maybe even completely...
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DYNAMIC POSITIONING CAPABILITY ASSESSMENT BASED ON OPTIMAL THRUST ALLOCATION
PublicationThe article presents an efficient method of optimal thrust allocation over the actuators in a dynamically positioned ship, according to the DNV-ST-0111 standard, Level 1. The optimisation task is approximated to a convex problem with linear constraints and mathematically formulated as quadratic programming. The case study is being used to illustrate the use of the proposed approach in assessing the DP capability of a rescue ship....
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Impact of Propeller Emergence on Hull, Propeller, Engine, and Fuel Consumption Performance in Regular Head Waves
PublicationIn this study, the impact of propeller emergence on the performance of a ship (speed), propeller (thrust, torque, and RPM), a diesel engine (torque and RPM) and fuel consumption are analysed under severe sea conditions. The goal is to describe the variation in the system variables and fuel consumption rather than analysing the motion of the ship or the phenomenon of propeller ventilation in itself. A mathematical model of the...
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HYDROACOUSTIC NOISE MEASUREMENTS
PublicationThe paper deals mainly with investigation of underwater noise that propagation is in shallow water. In this paper has been presented the experimental investigation results concerning the distribution of the sound field pressure generated by moving ships in the shallow water at the small distance from the ship. The main acoustical characteristics describing features of the field are spectrograms in pseudo 3D system – distance and frequency...
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The role of low-energy electrons in the charging process of LISA test masses
PublicationThe estimate of the total electron yield is fundamental for our understanding of the test-mass charging associated with cosmic rays in the Laser Interferometer Space Antenna (LISA) Pathfinder mission and in the forthcoming gravitational wave observatory LISA. To unveil the role of low energy electrons in this process owing to galactic and solar energetic particle events, in this work we study the interaction of keV and sub-keV...
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Digital microcontroller for sonar waveform generator
PublicationGenerating sounding signals is essential for the operation of active sonar. The system should be highly reliable. This can be achieved through architecture, communication between the devices, and a well-designed and self–testing software. The system presented in the article is responsible for the generation of hydroacoustic sounding signals, and ensures proper interaction between power amplifiers and power supplies. Thanks to its...
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A method of risk and safety assessment during the ship salvage using the hazard, release and consequence analysis = Metoda oceny ryzyka i bezpieczeństwa w czasie ratowania statku uszkodzonego przy użyciu analizy zagrożeń, uwolnień i konsekwencji wypadku
PublicationW pracy przedstawiono metody oceny bezpieczeństwa statków w stanie uszkodzonym proponowane przez IMO. Przedstawiono proponowaną metodę oceny bezpieczeństwa statku w stanie uszkodzonym. Opisano podstawowe elementy analizy ryzyka wraz z modelem ryzyka nieprzetrwania katastrofy przez statek.
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Searching for Critical Conditions During Lifeboat Launching – Simulations
PublicationThe 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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Architektura przyszłości – przekraczanie granic poprzez interfejsy
PublicationArchitektura przyszłości rozpatrywana jest w kontekście rozwoju technologii cyfrowych, które umożliwiają nadawanie obiektom architektonicznym cech interfejsów. Przekraczanie granic dotyczy więc nadawania architekturze nowych funkcji - funkcjonalności zapożyczonych ze świata wirtualnego, emisji informacji oraz interakcji. W tym ujęciu „interfejs architektoniczny” stanowi płaszczyznę komunikacji pomiędzy obiektem architektonicznym...
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Weather Routing System Architecture Using Onboard Data Collection and Route Optimisation
PublicationThis paper describes the architecture of a weather routing system consisting of two key elements: onboard monitoring and route optimiser sub-systems. The former is responsible for collecting various onboard measurements, such as current ship position or ship motion variables. These data, when gathered and processed, are then used for fine-tuning a ship model. The model, together with weather forecasts, is utilised by a multi-objective...
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Application of advanced CFD simulations in seakeeping analysis of ships (case study)
PublicationThe novel design process of many types of ships needs estimation of seakeeping properties. Especially ships like Offshore Supply Vessels, Wind Farm Support Vessels, Research Vessels, ferries, military vessels, rescue vessels require extended analysis of ship behavior on rough sea. The main reason for improving ships operability in different sea conditions is need of rising efficiency of propulsion system, reducing hull added resistance,...
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Images of the Seabed of the Gulf of Gdansk Obtained by Means of the Parametric Sonar
PublicationThe main goal of this paper is to present results of the experimental investigation of the seabed by means of parametric echosounder in the form of chosen images. The phenomena of nonlinear interaction between two parallel beams of high intensity gives as a results very narrow beam of low frequency wave, that enables to penetrate the sea bottom. The first step of our investigations was calibration of all the elements of the measuring...
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A method for preliminary estimation of the length of midship body block to be inserted during ship’s conversion
PublicationThe paper presents a method for preliminary estimation of the length of the midship body block, which inserted in the original hull, increases the deadweight of the ship in line with a required quantity. The method may be useful for establishing the scope of conversion to better adjust the ship for transportation tasks. The problem is formulated by using a mathematical model so selected that its solution, under set of assumptions,...
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Redundancja jako sposób zwiększenia niezawodności siłowni okrętowych
PublicationJednym z istotnych sposobów zapewnienia wysokiego poziomu niezawodności siłowni okrętowych jest zaprojektowanie redundancji jego elementów strukturalnych, np.: nadmiarowości strukturalnej systemów generowania energii, układów napędowych itp. W niniejszym artykule omówiono zagadnienia związane z nadmiarem, jako sposobem zwiększenia niezawodności systemów generowania energii i napędu statku. W szczególności zaś zostały zaprezentowane...