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Wyniki wyszukiwania dla: NUCLEAR PROPULSION
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Large size LSO:Ce and YSO:Ce scintillators for 50 MeV range γ-ray detector
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New fast photomultipliers with a screening grid at the anode
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Low energy γ-rays scintillation detection with large area avalanche photodiodes
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Comparison of the scintillation properties of LSO:Ce manufactured by different laboratories and of LGSO:Ce
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Cerium-doped orthophosphates: new promising scintillators
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Evaluation of new photonis XP1472 nine-channel photomultiplier
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YSO, LSO, GSO and LGSO. A study of energy resolution and nonproportionality
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Toenail selenium level among healthy residents of two polish districts
PublikacjaCelem pracy było badanie zawartości selenu w próbkach paznokci pobranych od mieszkańców Województwa Pomorskiego i Lubuskiego. Wykazano, że średnie stężenia Se w próbkach paznokci wynosiło odpowiednio 0,57 ± 0,10, 0,60 ± 0,16 mg kg-1. Stwierdzono także, że płeć, wiek, wskaźnik masy ciała, status palenia oraz przyjmowanie Se w postaci suplementów diety przez uczestników badania wpływa istotnie statystycznie na poziom...
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Assessment of atmospheric inorganic pollution in the urban region of Gdańsk, Northern Poland
PublikacjaProjekt wykonano w przemysłowej części Gdańska w celu zidentyfikowania głównych źródeł zanieczyszczeń. Próbki suchego oraz żywego (w hodowli hydroponicznej) mchu eksponowano równolegle w celu określenia ich właściwości kumulacji w aspekcie badań biomonitoringowych. Analizę chemiczną składu próbek mchu wykonano dzięki zastosowaniu techniki aktywacji neutronowej i reaktorze badawczym w Delft (Holandia). Uzyskane wyniki wskazują,...
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WATER LUBRICATED MAIN SHAFT BEARINGS - MODERN SOLUTION FOR HYDROPOWER INDUSTRY - Experimental and theoretical studies
PublikacjaWater-lubricated bearings are finding increasingly wide use in various branches of industry. As such, they may also be encountered in hydro power industry. They are also increasingly frequently employed in bearing systems of marine shaft propulsions and water pumps [1]. This rising popularity is due to a number of reasons [2]. First of all, their simple construction has direct impact on the level of pricing which is usually quite...
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Approximation of Fractional Order Dynamic Systems Using Elman, GRU and LSTM Neural Networks
PublikacjaIn the paper, authors explore the possibility of using the recurrent neural networks (RNN) - Elman, GRU and LSTM - for an approximation of the solution of the fractional-orders differential equations. The RNN network parameters are estimated via optimisation with the second order L-BFGS algorithm. It is done based on data from four systems: simple first and second fractional order LTI systems, a system of fractional-order point...
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Weather Hazard Avoidance in Modeling Safety of Motor-Driven Ship for Multicriteria Weather Routing
PublikacjaWeather routing methods find the most suitable ocean?s route for a vessel, taking into account changeable weather conditions and navigational constraints. In the multicriteria approach based on the evolutionary SPEA algorithm one is able to consider a few constrained criteria simultaneously. The approach applied for a ship with hybrid propulsions has already been presented by one of the authors on previous TransNav?2009. This time...
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Synthesis of Novel Polycationic Quaternary Di- and Trispirocyclic Benzenes
PublikacjaTreatment of hexakis(bromomethyl)benzene with a cyclic amine {morpholine, 1-methylpiperazine, 1-(2-hydroxyethyl)piperazine, isonipecotamide, 4-hydroxypiperidine, 4-[3-(4-piperidyl)propyl]-1-piperidineethanol} gave a range of di- and trispirocyclic ammonium salts in satisfactory yields (22-62%). Presumably, the electrostatic and repulsion forces play an important role in their formation. The structure in soln. and the protonation...
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PROPELLER INVESTIGATIONS BY MEANS OF NUMERICAL SIMULATION
PublikacjaThe analyses of hydroacoustics are of high interest at the moment due to strong impact of hydroacoustic phenomena on marine environment; the noises, generated e.g. by marine traffic, may be harmful for sea life. The analyses presented here are focused on one of main sources of noises generated by ships, i.e. cavitating propeller. The goal of the work is the assessment of the cavitation phenomenon, carried out with the standard...
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Development of trolleybus public transport in Gdynia as part of sustainable mobility strategy
PublikacjaIn many EU cities trolleybuses are experiencing a period of revitalization. New lines, new and modern trolley-buses, the use of auxiliary propulsion battery, eco-logical values and others, create great opportunities for that kind of public transport as an effective tool to shape transport policy in accordance with the principles of sustainable mobility. Gdynia is one of three cities in Poland with trolleybuses public transport...
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Balancing energy processes in turbine engines
PublikacjaThe article discusses the issue of balancing energy processes in turbine engines in operation in aeronautic and PDULQHSURSXOVLRQV\VWHPVZLWKWKHDLPWRDQDO\VHDQGHYDOXDWH EDVLFRSHUDWLQJSDUDPHWHUV7KH¿UVWSDUWSUHVHQWV the problem of enormous amounts of energy needed for driving fans and compressors of the largest contemporary turbofan engines commonly used in long-distance aviation. The amounts of the transmitted power and the effect RIÀRZSDUDPHWHUVDQGFRQVWUXFWLRQDOSURSHUWLHVRIWKHHQJLQHV RQWKHLUSHUIRUPDQFHDQGUHDOHI¿FLHQF\DUH evaluated....
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Mathemathical model of radial passive magnetic bearing
PublikacjaIn the article mathematical radial model of passive magnetic bearings to ocean engineering units has been presented. The units application in underwater thrusters should increase propulsion systems durability and gives lower maintenance costs. The rotor of electric motor is hanging in magnetic field taken from radial passive magnetic bearings. However axial direction maintenance must be controlled with electromagnets and their...
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Supporting development of the smart ship technology by CFD simulation of ship behavior in close to real operational conditions
PublikacjaThe shipping industry is at the milestone of technological development – autonomous ships. Involving smart technologies accelerates development of green and safe shipping. Also IMO regulations, especially EEDI en-hanced application of new technologies. Meeting economic and ecological requirements future ships need to be designed with respect to increased reliability and operational performance. Design process of ships may be improved...
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The newly developed multipurpose ROV or an integrated mine hunting system
PublikacjaA modular mine hunting ROV concept is presented. The design is based on experience gained during 15 years of exploitation of the Ukwial ROV and development of Gluptak single shot mine hunting systems. The design goal was to multiply capabilities of the Ukwial without increasing weight and dimensional envelope. The vehicle is composed around powerful propulsion system that gives the system basic PVDS capability and mine disposal...
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Application of advanced CFD simulations in seakeeping analysis of ships (case study)
PublikacjaThe 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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A commercial of the shelf components for a unmanned air vehicle photogrammetry
PublikacjaA photogrammetry from a unmanned aerial vehicle (UAV) can be understood as a new measurement tool. Is introduces a low-cost alternatives for a traditional aerial photogrammetry. A commercial off-the-shelf products (COTS), that are commercially available for a costumers, are the standard manufactures products, not custom. COTS products are available in the commercial market and can be bought and used under government contract. That...
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A CONCEPT OF DETERMINING THE RELATION BETWEEN LOAD AND WEAR OF TRIBOLOGICAL SYSTEMS OF SHIP MAIN SELF-IGNITION ENGINES BY USING PROBABILISTIC APPROACH PROBABILISTIC APPROACH
PublikacjaThis paper presents a proposal of simultaneous consideration of load and wear associated with it , of tribological systems of ship main engines (intended for ship propulsion) . Based on results of investigations it was assumed that both the load Q (i.e. a cause of wear ) and the wear Z (i.e. an effect of load occurrence) considered in a given time t(0 ≤ t ≤ t) are random variables Qt and Zt, respectively. There was characterized...
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Wytwarzanie energii elektrycznej - diagnoza i terapia
PublikacjaW artykule przeanalizowano stan i dalszy rozwój krajowego sektora wytwarzania energii elektrycznej w świetle najnowszych raportów Międzynarodowej Agencji Energetycznej, wskazujących potencjalne trendy i perspektywy w światowej energetyce. Na tle przewidywanego wzrostu zapotrzebowania na energię elektryczną wskazano na możliwość istotnego ograniczenia emisji CO2 drogą zastąpienia przestarzałych, nieefektywnych...
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How acidic amino acid residues facilitate DNA target site selection
PublikacjaDespite the negative charge of the DNA backbone, acidic residues (Asp/Glu) commonly participate in the base readout, with a strong preference for cytosine. In fact, in the solved DNA/protein structures, cytosine is recognized almost exclusively by Asp/Glu through a direct hydrogen bond, while at the same time, adenine, regardless of its amino group, shows no propensity for Asp/Glu. Here, we analyzed the contribution of Asp/Glu...
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Immersive Technologies that Aid Additive Manufacturing Processes in CBRN Defence Industry
PublikacjaTesting unique devices or their counterparts for CBRN (C-chemical, B-biological, R-radiological, N-nuclear) defense relies on additive manufacturing processes. Immersive technologies aid additive manufacturing. Their use not only helps understand the manufacturing processes, but also improves the design and quality of the products. This article aims to propose an approach to testing CBRN reconnaissance hand-held products developed...
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Experimental study of flow boiling pressure drop and heat transfer of R1233zd(E) at moderate and high saturation temperatures
PublikacjaThe paper presents the results of experimental study of flow boiling of R1233zd(E) in minichannel at moderate and high saturation temperatures. The heat transfer coefficient and pressure drop were measured for flow boiling in a stainless steel tube with 2 mm inside diameter and a length of 300 mm. Experiment has been conducted for saturation temperatures ranging from 83 to 145 °C which corresponds to values of reduced pressures...
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Carbon dioxide potential reduction using Start-Stop system in a car
PublikacjaOperating fuel consumption increases significantly when the vehicle stops frequently while driving or when the engine is idling during braking. In such cases, the internal combustion engine consumes the fuel but the mechanical energy is not used by the drive system. The amount of fuel that is consumed in this time by the engine can potentially be saved if the car is equipped with a Stop-Start system. Start-Stop system automatically...
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Four Degree-of-Freedom Hydrodynamic Maneuvering Model of a Small Azipod-Actuated Ship With Application to Onboard Decision Support Systems
PublikacjaThe main contribution of this paper is a numerical ship motion model of NTNU’s research vessel Gunnerus, capturing the surge, sway, roll, and yaw dynamics when sailing in uniform and steady currents. The model utilizes a crossflow drag formulation for the transverse viscous loads, and it includes a nonlinear formulation for the propulsion and steering loads provided by two azipod thrusters. A wide range of experimental data obtained...
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Biomimetic torene shells
PublikacjaThe genome inside the eukaryotic cells is guarded by a unique shell structure, called the nuclear envelope (NE), made of lipid membranes. This structure has an ultra torus topology with thousands of torus-shaped holes that imparts the structure a high flexural stiffness. Inspired from this biological design, here we present a novel ‘‘torene’’ architecture to design lightweight shell structures with ultra-stiffness for engineering...
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Recent Developments in Data-Assisted Modeling of Flexible Proteins
PublikacjaMany proteins can fold into well-defined conformations. However, intrinsically-disordered proteins (IDPs) do not possess a defined structure. Moreover, folded multi-domain proteins often digress into alternative conformations. Collectively, the conformational dynamics enables these proteins to fulfill specific functions. Thus, most experimental observables are averaged over the conformations that constitute an ensemble. In this...
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Two-step Conversion of Crude Glycerol Generated by Biodiesel Production into Biopolyols: Synthesis, Structural and Physical Chemical Characterization
PublikacjaIn this work biopolyols were synthesized via two-step process from crude glycerol and castor oil. For better evaluation of analyzed process, the impact of its time and temperature on the structure and properties of biopolyols was determined. Obtained results fully justified conducting of synthesis in two steps. Prepared materials were characterized by hydroxyl value and water content comparable to polyols industrially applied in...
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Relativistic two-dimensional hydrogen-like atom in a weak magnetic field
PublikacjaA two-dimensional (2D) hydrogen-like atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first- and second-order Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The second-order calculations are...
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Unraveling the Interplay between DNA and Proteins: A Computational Exploration of Sequence and Structure-Specific Recognition Mechanisms
PublikacjaMy PhD dissertation focused on DNA-protein interactions and the recognition of specific DNA sequences and structures. I discovered that acidic amino acid residues (Asp/Glu) play a crucial role by exhibiting a preference for cytosine. Their contribution to binding affinity depends on nearby cytosines, balancing electrostatic repulsion with specific interactions. Acidic residues act as negative selectors, discouraging non-cytosine...
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Water-Lubricated Journal Bearings Marine Applications, Design, and Operational Problems and Solutions
PublikacjaWater-Lubricated Journal Bearings: Marine Applications, Design, and Operational Problems and Solutions provides cutting-edge design solutions, common problems and methods for avoiding them, and material selection considerations for the use of water-lubricated journal bearings in marine environments. These bearings have many advantages, including the absence of the potential for oil contamination. They are also sensitive, and their...
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TEST FOR ASSESSING THE ENERGY EFFICIENCY OF VEHICLES WITH INTERNAL COMBUSTION ENGINES
PublikacjaThe most popular method for assessing the energy efficiency of vehicles is to compare the fuel consumption achieved in the conditions of selected approval test. Operating conditions are defined using the speed profiles, usually for only two categories: urban and extra-urban driving. Assessing the energy efficiency of vehicles should be performed using a more detailed classification of conditions. Presented results of comparison...
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Trim Optimisation - Theory and Practice
PublikacjaForce Technology has been working intensively with trim optimisation tests for almost last 10 years. Focus has primarily been put on the possible power savings and exhaust gases reduction. This paper describes the trim optimisation process for a large cargo vessel. The physics behind changed propulsive power is described and the analyses in order to elaborate the optimum trimmed conditions are presented. Different methods for prediction...
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Magnetizabilities of relativistic hydrogenlike atoms in some arbitrary discrete energy eigenstates
PublikacjaWe present the results of numerical calculations of magnetizability of the relativistic hydrogenlike atoms. Exploiting the analytical formula for $\chi$ we have found the values of the magnetizability for the ground state and for the first and the second set of excited states of the atom. The results for ions with the atomic number $0
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Magnetic-dipole-to-electric-quadrupole cross-susceptibilities for relativistic hydrogenlike atoms in some low-lying discrete energy eigenstates
PublikacjaIn this paper we present tabulated data for magnetic-dipole-to-electric-quadrupole cross-susceptibilities (χ_{M1→E2}) for Dirac one-electron atoms with a pointlike, spinless and motionless nucleus of charge Ze. Numerical values of this susceptibility for the hydrogen atom (Z = 1) and for hydrogenic ions with 2 \leqslant Z \leqslant 137 are computed from the general analytical formula, recently derived by us (Stefanska, 2016), valid...
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Potential energy curves, transition and permanent dipole moments of KRb
PublikacjaWe present extensive calculations of 48 adiabatic potential energy curves of the KRb molecule. Efforts have been focused on preparing the appropriate basis sets. Compared to previous approaches, the set of new potential energy curves is extended to higher excitations, including the single-excited K(4s2S)+Rb(5d2D) and double-excited K(4p2P)+Rb(5p2P) atomic limits. Larger distances between nuclei are also taken into account. New...
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Transition dipole moments of the lithium dimer
PublikacjaIn addition to knowledge of interatomic adiabatic potential energy curves of diatomic systems, it is essential to know electronic transition dipole moments. They are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping. Here, we present electronic transition dipole moments calculated for 74 allowed transitions between 26 states of Li2 [P. Jasik, J.E. Sienkiewicz, Chem. Phys. 323 (2006)...
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Dia- and paramagnetic contributions to magnetizabilities of relativistic hydrogenlike atoms in some low-lying discrete energy eigenstates
PublikacjaIn this paper we present tabulated data for relative diamagnetic and paramagentic contributions to the magnetizability ($\chi$) of the relativistic hydrogenlike atoms with a pointlike, motionless and spinless nucleus of charge $Ze$. Utilizing general analytical formulas for the diamagnetic ($\chi_{d}$) and paramagnetic ($\chi_{p}$) components of $\chi$, recently derived by us [P. Stefa{\'n}ska, 2020] with the aid of the Gordon...
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Neural modelling of dynamic systems with time delays based on an adjusted NEAT algorithm
PublikacjaA problem related to the development of an algorithm designed to find an architecture of artificial neural network used for black-box modelling of dynamic systems with time delays has been addressed in this paper. The proposed algorithm is based on a well-known NeuroEvolution of Augmenting Topologies (NEAT) algorithm. The NEAT algorithm has been adjusted by allowing additional connections within an artificial neural network and...
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ANALIZA MOŻLIWOŚCI ZASTOSOWANIA STEROWANIA PREDYKCYJNEGO TURBINĄ PAROWĄ ELEKTROWNI JĄDROWEJ
PublikacjaArtykuł przedstawia wyniki wstępnej analizy możliwości zastosowania sterowania predykcyjnego MPC turbiną parową elektrowni jądrowej. Tradycyjnie przyjmuje się, że turbina pracuje w jednym punkcie pracy odpowiadającym jej mocy nominalnej, co pozwala na stosowanie klasycznych regulatorów PID. Synteza sterowania dla warunków zmiennego punktu pracy wymaga uwzględnienia nieliniowego charakteru procesów turbiny oraz możliwości naruszania...
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COMPARATIVE ANALYSIS OF RESULTS OF APPLICATION OF MARKOV AND SEMI-MARKOV PROCESSES TO RELIABILITY MODELS OF MULTI-STATE TECHNICAL OBJECTS
PublikacjaDuring rational operation of technical objects and systems various operational decisions are made and decision-making process itself should be consisted in selecting that considered most favourable out of all possible to be taken. Choice of such decision is possible after taking into account many different information items but it never be completely correct without accounting for data and indices dealing with reliability. In...
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Feasibility of combined diesel engine - steam turbine in power station operating in the maritime
PublikacjaCompression-ignition engines used in ship technology as main propulsion engines are large units reaching even to 50-60 MW. Currently, the efficiency of such engines amounts to 45-50%. With such a large power unit, exhaust gases leaving the engine contain very large quantities of heat available for further treatment. Exhaust gases from the piston engine contain about 25% of the heat supplied to the engine in the fuel. Using the...
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BASECOL2023 scientific content
PublikacjaContext. The global context of making numerous data produced by researchers available requires collecting and organising the data, assigning meaningful metadata, and presenting the data in a meaningful and homogeneous way. The BASECOL database, which collects inelastic rate coefficients for application to the interstellar medium and to circumstellar and cometary atmospheres, meets those requirements. Aims. We aim to present the...
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Creating Polish space language dictionary - lessons learned
PublikacjaPolish space industry suffers from lack of space vocabulary. Since joining European Space Agency in 2012, the sector has expanded rapidly now employing over 1000 specialists focusing mainly on space sustainability, space debris detection and tracking, robotics and propulsion systems. The Polish Space Agency together with The Polish Committee for Standardization have committed to creating the first lexicon of space language, along...
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Application of the IMO standard manoeuvres procedure for pod-driven ships
PublikacjaInternational Maritime Organisation (IMO) in the resolution MSC.137(76) Standards for Ship manoeuvrability presents the manoeuvring criteria that has to be satisfied by majority of seagoing ships. Together with the criteria, procedures for carrying out the manoeuvring tests are also presented. They however do not correspond directly to ships with non-conventional steering-propulsion devices, like pod drives. IMO is aware of this...
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Full scale CFD seakeeping simulations for case study ship redesigned from V-shaped bulbous bow to X-bow hull form
PublikacjaIncreasing 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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Experimental determination of general characteristic of internal combustion engine using mobile test bench connected via Power Take-Off unit
PublikacjaThe general characteristics of the engine include information about the regions of the engine's operating area that are most efficient, where specific fuel consumption reaches the smallest values. Economic operation based on those characteristics can contribute to a significant reduction of fuel consumption and consequently less pollutant emissions and lower costs. The paper presents an experimental method of determination of general...