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Search results for: EFM
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Proces ciągłego doskonalenia wśród laureatów XXIII edycji Konkursu o Pomorską Nagrodę Jakości
PublicationModel doskonałości można zdefiniować jako zbiór zasad kompleksowej oceny organizacji, który często wykorzystywany jest jako podstawa konkursów jakości. Europejski Model Doskonałości EFQM pozwala na doskonalenie organizacji m.in. poprzez kompleksowe podejście, identyfikację mocnych i słabych stron organizacji czy zwiększenie zaangażowania pracowników w doskonalenie. Celem niniejszego referatu jest analiza działań doskonalących...
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Nonlinear dynamic analysis of the pure “buckling” mechanism during blow-out trauma of the human orbit
PublicationConsidering the interplay between orbital bones and intraorbital soft tissues, commonly accepted patterns of the blow-out type of trauma within the human orbit require more thorough investigation to assess the minimal health-threatening impact value. Two different three-dimensional finite element method (FEM) models of the human orbital region were developed to simulate the pure “buckling” mechanism of orbital wall fracture in...
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Adjusting the Stiffness of Supports during Milling of a Large-Size Workpiece Using the Salp Swarm Algorithm
PublicationThis paper concerns the problem of vibration reduction during milling. For this purpose, it is proposed that the standard supports of the workpiece be replaced with adjustable stiffness supports. This affects the modal parameters of the whole system, i.e., object and its supports, which is essential from the point of view of the relative tool–workpiece vibrations. To reduce the vibration level during milling, it is necessary to...
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Boron-Doped Diamond/GaN Heterojunction—The Influence of the Low-Temperature Deposition
PublicationWe report a method of growing a boron-doped diamond film by plasma-assisted chemical vapour deposition utilizing a pre-treatment of GaN substrate to give a high density of nucleation. CVD diamond was deposited on GaN substrate grown epitaxially via the molecular-beam epitaxy process. To obtain a continuous diamond film with the presence of well-developed grains, the GaN substrates are exposed to hydrogen plasma prior to deposition....
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Load-settlement characteristics of piles working in a group
PublicationLoad-settlement characteristic (Q-s) of an axially loaded pile can be empirically determined from a static pile load test or on the basis of calculations using, e.g. transfer functions or numerical methods (FEM). The transfer functions method usually rely on empirical data, i.e. the function parameters are determined on the basis of numerous pile test results. Thus this method takes into account pile installation technology and...
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Theoretical Assessment of Excited State Gradients and Resonance Raman Intensities for the Azobenzene Molecule
PublicationThe ground state geometries and vibrational frequencies as well as the excitation energies and excited state gradients of the S 1(nπ*) and S 2(ππ * ) states of trans - and cis -azobenzene are investigated by several DFT methods, namely B3LYP, PBE, M06-2X, CAM-B3LYP, and ω B97X. Excited state properties and in particular gradients are also assessed using the wave function based methods EOM-CCSD and RASPT2/RASSCF. Comparison with...
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Communication and Load Balancing Optimization for Finite Element Electromagnetic Simulations Using Multi-GPU Workstation
PublicationThis paper considers a method for accelerating finite-element simulations of electromagnetic problems on a workstation using graphics processing units (GPUs). The focus is on finite-element formulations using higher order elements and tetrahedral meshes that lead to sparse matrices too large to be dealt with on a typical workstation using direct methods. We discuss the problem of rapid matrix generation and assembly, as well as...
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Rozkład naprężeń mechanicznych w łyżce o szerokości 500 mm, przeznaczonej do koparki podsiębiernej
PublicationW artykule zaprezentowano optymalizację kształtu łyżki koparki przedsiębiernej z wykorzystaniem analizy wytrzymałościowej. Analizę oparto na trójwymiarowym modelu konstrukcji łyżki z zastosowaniem metody elementów skończonych (MES). Opracowanie wspomnianej metody pozwoliło na modyfikację konstrukcji łyżki, która dała w efekcie obniżenie naprężeń złożonych w newralgicznych obszarach konstrukcji łyżki. Przedstawiona analiza okazała...
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Arch bridges under test loadings
PublicationThis paper illustrates experience in arch bridges test loadings of the research team of Department of Structural Mechanics and Bridge Structures from the Gdansk University of Technology. The presented calculations results constist the analysis of spatial construction schemes made using the finite elements method (FEM) and its comparison to the field studies. Arch bridges with the longest spans, visualisation of the computational...
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Computations of critical load value of composite shell with random geometric imperfections
PublicationThe work presents the numerical analysis of composite shell with geometric imperfections subjected to compression along its generatrix. The imperfections are described as single indentations and random fields with random parameters of shape and correlation. The fields are generated with the use of the authors made program. Using the authors’ FEM software as well as commercial package Femap with NX Nastran, the critical load values...
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Chemical characteristics of new nanopowder of titania doped with nitrogen atoms
PublicationW pracy zaprezentowano charakterystykę domieszkowanego azotem ditlenku tytanu otrzymanego na drodze jednoetapowej syntezy z kompleksu tytanu (IV) z ligandami zawierającymi atomy azotu. ikrostruktura i morfologia nowego materiału została określony za pomocą badań XRD, AFM, UV-VIS i FT-IR. Raport przedstawia również badania elektrochemiczne, które pozowliły na wyznaczenie potencjału pasma płaskiego na podstawie wykresu Mott
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Simulation of the switched reluctance drive system
PublicationSwitched reluctance motors (SRM), unlike other types of motors, for their application require a control system and the supply from a power electronic converter. A method of modelling and mathematical model of an SRM in a switched reluctance drive (SRD) system is presented in the paper. Modelling is based on Lagrange's energy method. Coefficients of the Lagrange's equation have been calculated using the finite element method (FEM)....
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Reliability estimation of underground horizontal fuel tank limit states
PublicationFuel tanks are designed with regard to standard loads and operating conditions. The investigations of the paper show the impact of such factors as tank corrosion and other means on the variation of stress fields and deformation of the underground horizontal tank shell. The introduction of probabilistic methods allows for structural reliability assessment. While the computational time of the entire tank FEM model is high, the preliminary...
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Doskonalenie logistycznego łańcucha dostaw w usługach w ujęciu relacyjnym
PublicationW literaturze zagadnienia związane z modelami doskonałości zarządzania łańcuchem dostaw, modelami zarządzania relacjami, modelami doskonałości EFQM oraz obszarami logistycznymi funkcjonują rozłącznie. Opracowany model w postaci MAPY RELACJI pozwala na pokazanie jak wyglądają korelacje między obszarami logistycznymi, obszarami działalności w odniesieniu do modeli doskonałości EFQM, modelami doskonałości zarządzania łańcuchem dostaw...
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Ocena efektywności przedsięwzięć informatycznych w przedsiębiorstwie
PublicationPrzedmiotem badania rozprawy doktorskiej była metodologia oceny efektywności przedsięwzięć informatycznych w przedsiębiorstwie. Celem badawczym rozprawy było stworzenie skutecznej i bardziej jednoznacznej metody oceny efektywności przedsięwzięć informatycznych w przedsiębiorstwie, opartej o koncepcję adaptacyjną, która pozwalałaby uwzględniać szczególne warunki panujące...
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Badanie wpływu ruchu niższego priorytetu na jakość usług o wymaganiach czasu rzeczywistego w sieci IP QoS.
PublicationW artykule przedstawiono wyniki badań dotyczące wpływu rozkładu długości pakietów ruchu o niższym priorytecie na jakość usług o wymaganiach czasu rzeczywistego (real time services), korzystających ze schematu obsługi Expedited Forwarding Per Hop Behavior (EF PHB) w sieci IP QoS Differentiated Services (DiffServ). Wyniki zaprezentowane w referacie zostały uzyskane zarówno przy pomocy modeli analitycznych, opisujących gwarancje statystyczne...
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Zmodernizowany most Łazienkowski w Warszawie – analizy z wykorzystaniem modelu numerycznego MES
PublicationW artykule przedstawiono proces modelowania statycznego przęseł mostu Łazienkowskiego w Warszawie, który został poddany odbudowie po pożarze 14 lutego 2015 r. Sprawdzające obliczenia numeryczne wykonano w związku z badaniami konstrukcji podczas próbnego obciążenia. Przeprowadzono weryfikację obliczeń projektowych i zaprojektowano próbne obciążenie. Podsumowano wyniki analizy i badań. Dodatkowo opisano nową, stalową konstrukcję...
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Detection of cellulose production capacity of recombinant Escherichia coli strains BL21(DE3) and AAEC191A
Open Research DataBacteria that form biofilms generate an extracellular matrix (ECM), where cellulose stands out as a key constituent. An approach for assessing microorganisms' cellulose production involves using calcofluor white staining on colonies. In this method, a fluorescent dye (calcofluor-white) is introduced to a stable YESCA substrate composed of casamino acids,...
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Detection of cellulose production capacity of recombinant Escherichia coli strains BL21(DE3) and AAEC191A
Open Research DataBacteria that form biofilms generate an extracellular matrix (ECM), where cellulose stands out as a key constituent. An approach for assessing microorganisms' cellulose production involves using calcofluor white staining on colonies. In this method, a fluorescent dye (calcofluor-white) is introduced to a stable YESCA substrate composed of casamino acids,...
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Detection of cellulose production capacity of recombinant Escherichia coli strains BL21(DE3) and AAEC191A
Open Research DataBacteria that form biofilms generate an extracellular matrix (ECM), where cellulose stands out as a key constituent. An approach for assessing microorganisms' cellulose production involves using calcofluor white staining on colonies. In this method, a fluorescent dye (calcofluor-white) is introduced to a stable YESCA substrate composed of casamino acids,...
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Detection of cellulose production capacity of recombinant Escherichia coli strains BL21(DE3) and AAEC191A
Open Research DataBacteria that form biofilms generate an extracellular matrix (ECM), where cellulose stands out as a key constituent. An approach for assessing microorganisms' cellulose production involves using calcofluor white staining on colonies. In this method, a fluorescent dye (calcofluor-white) is introduced to a stable YESCA substrate composed of casamino acids,...
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Measurements of raising of 160EC pantograph type
Open Research DataIn this description the results of the experiment and also simulation performed on the total assembly of the 160 EC pantograph type is given. Multibody dynamics of pantograph rising due to external torque and forces are measured for parameter validation of the pantograph model.
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Comparative Analysis of Salient and Non-Salient Pole Brushless Synchronous Generator for Application in Autonomous Electric Power System
PublicationThis paper presents a comparative study of two types of brushless synchronous generator for application in autonomous electric power systems (e.g. airplane power grid). Commercially used salient pole and a prototype non-salient pole high speed multi-pole brushless synchronous generator (BSG) have been presented. Comparative analysis of both types of the generator has been performed. Chosen simulation (using FEM and circuit models)...
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Możliwości dostosowania istniejących bloków gazowo-parowych do utylizacji gazu niekonwencjonalnego w tym gazu łupkowego
PublicationW pracy omówiono modyfikację turbiny gazowej dostosowując ją do spalania gazu niekonwencjonalnego. Rozpatrzono aspekty termodynamiczne utylizacji gazu łupkowego we wspomnianej instalacji. W oparciu o analizy termodynamiczne określono sprawność obiegu gazowo-parowego. Analiza obiegu cieplnego została przeprowadzona za pomocą kodów CFM. Motywacją do podjęcia niniejszej pracy jest potrzeba dywersyfikacji źródeł energii w tym również...
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Determination of equivalent circuit parameters of an induction motor using field calculation software
PublicationSimulation of the drive system comprising a power electronic converter and an induction motor requires that the equivalent circuit parameters of the motor are known. These parameters can be either measured or calculated. A method of calculation of self and mutual inductances that are parameters of a polyphase model of the motor is presented in the paper. All self-inductances and mutual inductances have been calculated using the...
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The influence of hard segment crosslinking on the morphology and mechanical properties of segmented poly(ester-urethanes)
PublicationPrównano właściwości i morfologie usieciowanych trójmetylolopropanem (TMP) i nieusieciowanych poliestrouretanów formowanych reaktywnie. W nieusieciowanych poliestrouretanach stwierdzono za pomocą AFM obecność agregacji domen segmentów sztywnych o wymiarze 70-380 nm. W usieciowanych poliuretanach zaobserwowano jedynie jednolicie rozmieszczone domeny segmentów sztywnych wielkości 20 nm. Właściwości mechaniczne wyraźnie różniły się,...
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ECONOMICAL AND SAFE METHOD OF GRANULAR MATERIAL STORAGE IN SILOS IN OFFSHORE PORT TERMINALS
PublicationThe article discusses issues related with storage of granular materials in silos made of corrugated sheets and reinforced with vertical ribs. Advantages and disadvantages of these structures are named, and typical technological solutions used by largest silo producers are presented. Moreover, basic assumptions of Eurocode 3 are discussed in the context of determining the buckling load capacity of a ribbed jacket. Alternative methods...
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Thermal Transitions and Structural Characteristics of Poly(3,4-ethylenedioxythiophene/cucurbit[7]uril) Polypseudorotaxane and Polyrotaxane Thin Films
PublicationHerein, we report the thermal transitions and structural properties of poly(3,4-ethylenedioxythiophene/cucurbit[7]uril) pseudopolyrotaxane (PEDOT∙CB7-PS) and polyrotaxane (PEDOT∙CB7-PR) thin films compared with those of pristine PEDOT. The structural characteristics were investigated by using variable-temperature spectroscopic ellipsometry (VTSE), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and atomic force...
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Modeling of wood frame structures with different insulation materials under damaging dynamic loading
PublicationWood frame buildings are very popular in regions that are exposed to different dynamic excitations, such as damaging earthquakes. Their seismic resistance is really important in order to prevent structural damages and human losses. This paper presents the results of advanced numerical investigation carried out using the FEM. Based on the models of wall panels, the numerical model of real structure of the wood frame building has...
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Computationally Efficient Multi-Objective Optimization of and Experimental Validation of Yagi-Uda Antenna
PublicationIn this paper, computationally efficient multi-objective optimization of antenna structures is discussed. As a design case, we consider a multi-parameter planar Yagi-Uda antenna structure, featuring a driven element, three directors, and a feeding structure. Direct optimization of the high-fidelity electromagnetic (EM) antenna model is prohibitive in computational terms. Instead, our design methodology exploits response surface...
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Cost-Efficient Multi-Objective Design of Miniaturized Microwave Circuits Using Machine Learning and Artificial Neural Network
PublicationDesigning microwave components involves managing multiple objectives such as center frequencies, impedance matching, and size reduction for miniaturized structures. Traditional multi-objective optimization (MO) approaches heavily rely on computationally expensive population-based methods, especially when exe-cuted with full-wave electromagnetic (EM) analysis to guarantee reliability. This paper introduces a novel and cost-effective...
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On Nonlinear Bending Study of a Piezo-Flexomagnetic Nanobeam Based on an Analytical-Numerical Solution
PublicationAmong various magneto-elastic phenomena, flexomagnetic (FM) coupling can be defined as a dependence between strain gradient and magnetic polarization and, contrariwise, elastic strain and magnetic field gradient. This feature is a higher-order one than piezomagnetic, which is the magnetic response to strain. At the nanoscale, where large strain gradients are expected, the FM effect is significant and could be even dominant. In...
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Variable-fidelity response feature surrogates for accelerated statistical analysis and yield estimation of compact microwave components
PublicationAccounting for manufacturing tolerances is an essential part of a reliable microwave design process. Yet, quantification of geometry and/or material parameter uncertainties is challenging at the level of full-wave electromagnetic (EM) simulation models. This is due to inherently high cost of EM analysis and massive simulations necessary to conduct the statistical analysis. Here, a low-cost and accurate yield estimation procedure...
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Efficient Multi-Objective Simulation-Driven Antenna Design Using Co-Kriging
PublicationA methodology for fast multi-objective antenna optimization is presented. Our approach is based on response surface approximation (RSA) modeling and variable-fidelity electromagnetic (EM) simulations. In the design process, a computationally cheap RSA surrogate model constructed from sampled coarse-discretization EM antenna simulations is optimized using a multi-objective evolutionary algorithm. The initially determined Pareto...
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Expedited Design Closure of Antennas By Means Of Trust-Region-Based Adaptive Response Scaling
PublicationIn the letter, a reliable procedure for expedited design optimization of antenna structures by means of trust-region adaptive response scaling (TR-ARS) is proposed. The presented approach exploits two-level electromagnetic (EM) simulation models. A predicted high-fidelity model response is obtained by applying nonlinear frequency and amplitude correction to the low-fidelity model. The surrogate created this way is iteratively rebuilt...
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Analiza następstw potencjalnej awarii wanty mostu podwieszonego w Bydgoszczy
PublicationMost Uniwersytecki został zamknięty po siedmiu latach od oddania do użytkowania. Powodem były widoczne gołym okiem objawy znacznego przeciążenia w obrębie zakotwień. Krytyczne elementy konstrukcji mostu zostały wzmocnione i przywrócono go do ruchu. W artykule przedstawiono nieliniowe analizy statyczne i dynamiczne wykonane na modelu MES, prezentujące cztery scenariusze przebiegu zachowania konstrukcji po utracie nośności mocowania...
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ANALYSIS OF THE PUNCHING FAILURE MECHANISM IN WORKING PLATFORMS
PublicationPaper presents an analysis of the shear failure mechanism which occurs from the punching of a working platform layer in relation to its thickness, grain size arrangement and mechanical properties, taking into consideration the interaction with soft subgrade. The study is based on the observations of performance of natural scale structures (Streefkerk) and the results of model investigations numerically represented with the use...
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Analiza termodynamiczna niskoemisyjnego obiegu turbiny gazowo-parowej z zastosowaniem oksyspalania
PublicationW artykule przedstawiono analizę termodynamiczną modyfikacji bloku gazowego w niskoemisyjny obieg turbiny gazowo-parowej z zastosowaniem oksyspalania. Analiza termodynamiczna obiegu cieplnego przed i po modyfikacji została przeprowadzona za pomocą kodu numerycznego typu CFM. Obiegiem wyjściowym dla przeprowadzonych obliczeń jest obieg turbiny GT8C pracującej w Gorzowie Wielkopolskim. Następnie, zachowując sprawności podstawowych...
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Mesoscopic impedance analysis of solid materials surface
PublicationSeveral techniques have been developed in order to characterize electrical properties of surfaces in micrometer/nanometer scale. Obtaining of the spatial distribution of sample resistance, capacitance or potential requires separate measurements performed in different scanning modes. On the other hand, analysis of the frequency response of investigated system enables determination of several physical quantities in single measurement...
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Sensorless predictive control of three-phase parallel active filter
PublicationThe paper presents the control system of parallel active power filter (APF) with predictive reference current calculation and model based predictive current control. The novel estimator and predictor of grid emf is proposed for AC voltage sensorless operation of APF, regardless of distortion of this voltage. Proposed control system provides control of APF current with high precision and dynamics limited only by filter circuit parameters....
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THEORETICAL AND EXPERIMENTAL INVESTIGATION OF THIN-WALLED BEARING SHELL’S DESIGN PARAMETERS AND ASSEMBLY CONDITIONS ON THE HOLDING TORQUE INSIDE A HOUSING BORE OF A CONNECTING ROD
PublicationThe aim of the work was the experimental and theoretical evaluation of the influence of the most important parameters determining the holding torque of a thin-walled bearing shell inside a housing bore of a connecting rod. The main investigated parameters were defned by authors experience in this feld. In the frst stage of research, a special test stand was designed in order to allow measuring the real values of the friction torque...
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Detection of defects in PMMA beam using shear waves - numerical simulation and experiment
PublicationTest doświadczalny falami sprężystymi jest częścią systemu diagnostycznego belek. Autorzy badają pole przyspieszeń wywołane przepływem fal ultradźwiękowych i jego modyfikacje wynikające z wprowadzonych uszkodzeń belki. Artykuł porównuje wyniki eksperymentalne z symulacjami numerycznymi MES. The experimental test introduced in the paper is the part of the diagnostic system utilizing the elastic waves. The authors investigate the...
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Determination of leakage inductances of multi-winding and single-phase transformer
PublicationThis paper presents the method for determination of leakage inductances of single-phase and multi-winding transformer. The matrix of leakage inductances takes into account leakage self and also leakage mutual magnetic couplings. It is assumed that there is a flux common to all windings and several leakage fluxes referred to a particular winding. The flux linkages of each coil needed fo calculation of leakage inductances was computed...
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Strength parameters of masonry walls in modelling historic constructions
PublicationThe paper presents the determination of the basic material properties of a historic brickwork. Experimental studies were used to identify the basic material properties of bricks. The mechanical properties of the masonry, as an orthotropic homogenized material, were calculated. Then, numerical simulations using the Finite Element Method (FEM) were performed to verify the experimental outcomes. Macromodels with element sizes of 40,...
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Special Issue "Applications of Finite Element Modeling for Mechanical and Mechatronic Systems"
PublicationNumerical modeling is very important in today's engineering because, among other things, it reduces the costs associated with prototyping or predicting the occurrence of potentially dangerous situations during operation in certain defined conditions. Different methods have so far been used to implement the real structure into the numerical version. The most popular have been variations of the finite element method (FEM). The aim...
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FEA analysis of the multicell piezoelectric motor
PublicationThe presented paper concerns a design, modeling and chosen tests of the prototype multicell piezoelectric motor (MPM). The principle of operation based on three independent traveling wave actuators is presented. The main materials and technologies used in the fabrication process are described. The structure of the motor is modeled using static and modal FEM analysis. The process of traveling wave generation in the MPM structure...
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DYNAMIC RESPONSE OF FORUM GDANSK STRUCTURE DUE TO RAIL TRAFFIC
PublicationThe paper presents the study of the impact of vibration induced by the movement of the railway rolling stock on the Forum Gdańsk structure. This object is currently under construction and is located over the railway tracks in the vicinity of the Gdańsk Główny and Gdańsk Śródmieście railway stations. The analysis covers the influence of vibrations on the structure itself and on the people within. The in situ measurements on existing...
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Numerical Studies on Propellers in Open Water and behind Hulls aiming to support the Evaluation of Propulsion Tests
PublicationA RANS based numerical analysis of propellers can contribute considerably to our understanding of propeller/hull interaction. It may also allow for a review of scaling procedures on results from experimental fluid dynamics (EFD). Using various RANS codes (Fluent, CFX, STAR-CCM+ and FreSCo+) on common test cases the authors first focused on propeller open water (POW) calculations. Next we simulated the propeller hull interaction...
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Launching of steel bridge girder. Application of nonlinear shell models
PublicationThe paper describes the final technology of launching the steel bridge superstructure. The original technology failed in the first construction stage. Local damage of steel webs caused by plastic buckling stopped the procedure. In the effect of damage a new consulting team was employed to solve the problem and redesign a technology of constructing. The key element of the new solution was developed with great help of non-linear...
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Silent Sonar with matched filtration
PublicationRadars with continuous wave frequency (CW FM sonars) are used in radiolocation as 'silent sonars'. They determine the distance to target by measuring the difference between the frequency of the sounding signal and echo signal. The article presents the principle of operation and parameters of silent CW FM sonars. Target distance determined by these sonars is based on the signal at the output of the matched filter. The Doppler effect...