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Search results for: mathematical modelling and identification
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Mathematical Modelling in Diagnosis of Wastewater Treatment Plant
PublicationThe paper reports development of mathematical modeling in diagnosis of the WWTP. The algorithm is based on a comparition of data from the mathematical modeling and measurments of real datefrom WWTP, until it will detect any malfunction of the sensors in th case of study.
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Mathematical modelling: Lessons from composite indicators
PublicationWe discuss here composite indicators as mathematical models, which can be looked at through the lenses of the five rules discussed in this volume. Composite indicators sit between analysis and advocacy, and their use has social and political implications. For this reason, the lenses of the manifesto can be used to build them better, to make them more transparent, as well as to inspect incumbent indicators for methodological or...
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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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Mathematical Modelling and Computer Simulation of Activated Sludge Systems
PublicationPrzegląd systemów osadu czynnego. Rozwój modeli procesu osadu czynnego. Podstawowe definicje z zakresu modelowania matematycznego i symulacji komputerowej. Proces budowy modelu (model biokinetyczny, hydrodynamiczny, transferu tlenu, temperatury). Modelowanie procesów biochemicznych zachodzących w systemach osadu czynnego. Organizacja badań symulacyjnych. Praktyczne zastosowania modeli osadu czynnego.
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Mathematical modelling and computer simulation of activated sludge systems.Second edition
PublicationMathematical Modelling and Computer Simulation of Activated Sludge Systems – Second Edition, provides, from the process engineering perspective, a comprehensive and up-to-date overview regarding various aspects of the mechanistic (“white box”) modelling and simulation of advanced activated sludge systems performing biological nutrient removal. In the new edition of the book, a special focus is given to nitrogen removal and an overview...
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Mathematical modelling of implant in an operated hernia for estimation of the repair persistence
PublicationThis paper presents mathematical modelling of an implanted surgical mesh used in the repair process of the abdominal hernia. The synthetic implant is simulated by a membrane structure. The author provides a material modelling of the implant based on the dense net model appropriate for technical fabrics. The accuracy of the proposed solution is evaluated by comparing the simulations of the dynamic behaviour of the system with the...
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Mathematical modelling of the overhead contact line for the purpose of diagnostics of pantographs
PublicationThe overhead contact line (OCL) is the most effective way for supplying railway electric vehicles. The increase of the speed of the vehicles increases power consumption and requires ensuring proper cooperation of pantographs with OCL. The paper describes the novel mathematical model of the OCL system and the simulation results. The primary objective is a more accurate analysis to increase the reliability of the evaluation of monitoring...
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Modelling and Identification of Tower Type Historic Buildings
PublicationW pracy omawia się problemy modelowania i identyfikacji zabytkowych murowanych budowli wieżowych na przykładzie wieży Twierdzy Wisłoujście. Przedstawiono analizę modalną na podstawie dwukierunkowych pomiarów przyspieszeń na 9 poziomach wieży. Wyniki analizy posłużyły do identyfikacji modelu matematycznego budowli w postaci sztywnego bloku na podłożu sprężystym. Wykorzystano hierarchiczną procedurę opartą na analizie wrażliwości.
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Mathematical Modelling of a Seismic Isolation System to Protect Structures During Damaging Earthquakes
PublicationThe present study aims to determine the effectiveness of a nonlinear mathematical model in simulating complex mechanical behaviour of a seismic isolation system to protect structures during strong and damaging earthquakes. In order to construct the Polymeric Bearings considered in this research, a specially prepared flexible polyurethane elastomer with increased damping properties has been used. The usefulness of the proposed mathematical...
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Mathematical Modelling of a Seismic Isolation System to Protect Structures during Damaging Earthquakes
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Mathematical Modelling and Effect Size Analysis in Support of Searching for the Proteomic Signature of Radiotherapy Toxicity
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Building wall boundary condition in mathematical modelling of built-up area rapid inundation
PublicationPrzedstawiono wyniki modelowania powodzi miejskiej przy pomocy dwuwymiarowych równań de Saint-Venanta. Równania rozwiązano metodą objętości skończonych. Przebadano wpływ rodzaju warunku brzegowego zadawanego na brzegach zamkniętych na wyniki obliczeń. Wyniki obliczeń porównano z pomiarami laboratoryjnymi, wykonanymi w Laboratorium hydraulicznym WILiŚ Politechniki Gdańskiej.
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Physical and mathematical modelling of implant-fascia system in order to improve laparoscopic repair of ventral hernia
PublicationThis paper describes an investigation of biomechanical behaviour of hernia repair, which is focused on the selection of safe linking of certain type of implant with fascia in laparoscopic operation. The strength of various fixations of the implant to the fascia is analysed. Methods: The research is based on experimental observations of operated hernia model behaviour during a dynamic impulse load corresponding to post-operative...
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Mathematical modelling of gasification process of sewage sludge in reactor of negative CO2 emission power plant
PublicationSewage sludge is a residue of wastewater processing that is biologically active and consists of water,organic matter, including dead and alive pathogens, as well as organic and inorganic contaminants suchas polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Due to the nature of sewage sludge and itspossible influence on human health and wellbeing, it is a subject of various regulations. Currently,sewage sludge is considered...
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Experimental and mathematical modelling study of gas combustion under the high-temperature and oxygen-deficient oxidizers
PublicationPraca przedstawia wyniki badań eksperymentalnych i modelowania numerycznego wpływu parametrów utleniacza za długość i objętość płomienia przy spalaniu paliwa gazowego w środowisku o wysokiej temperaturze i ubogim w tlen.
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Identification and non-integer order modelling of synchronous machines operating as generator
PublicationThis paper presents an original mathematical model of a synchronous generator using derivatives of fractional order. In contrast to classical models composed of a large number of R-L ladders, it comprises half-order impedances, which enable the accurate description of the electromagnetic induction phenomena in a wide frequency range, while minimizing the order and number of model parameters. The proposed model takes into account...
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Evaluation and behaviour of slowly biodegradable substrate on mathematical modelling of oxygen uptake rate in activated sludge systems
PublicationThe effect of the readily biodegradable (Ss) fraction in activated sludge systems has been extensively investigated, but only minor information can be found about the effect of Xs on OUR in activated sludge systems. The aim of this study was to determine the evaluation and behaviour of Xs on mathematical modelling of OUR using ASM2d and its modification. The essential study was divided into two major parts: experimental investigation...
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Sustainable nitrogen removal in anammox-mediated systems: Microbial metabolic pathways, operational conditions and mathematical modelling
PublicationAnammox-mediated systems have attracted considerable attention as alternative cost-effective technologies for sustainable nitrogen (N) removal from wastewater. This review comprehensively highlights the importance of understanding microbial metabolism in anammox-mediated systems under crucial operation parameters, indicating the potentially wide applications for the sustainable treatment of N-containing wastewater. The partial...
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Mathematical Modelling of Drive System with an Elastic Coupling Based on Formal Analogy between the Transmission Shaft and the Electric Transmission Line
PublicationIn the paper, the kinematic structure of the transmission shaft between the driving motor and the working mechanism is studied. The analysis is based on electrical and mechanical similarities. The equivalent circuits, typical for electrical systems, are defined for the transmission shaft concerned. Modelling of the transmission shaft based on a formal analogy between the transmission shaft and the electric transmission line is...
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Significant Parameters Identification for Optimal Modelling of the Harp-Type Flat-Plate Solar Collector
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Mathematical modelling of two-step nitrification-denitrification for treatment of sludge digester liquors: influence of nitrite (NO2-N) on the process kinetics
PublicationSeparate treatment of the sludge digester liquors is an alternative for expansion of the mainstream treatment line. In order to reduce the oxygen demand for nitrification and organic carbon demand for denitrification, a shortcut in the nitrogen conversion pathway has been promoted in recent years, i.e. nitrification-denitrification via NO2-N instead of NO3-N. Although NO2-N is a common intermediate product of nitrification and...
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Modelling and parameter identification of steel–concrete composite beams in 3D rigid finite element method
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Modelling of Objects Behaviour for Their Re-identification in Multi-camera Surveillance System Employing Particle Filters and Flow Graphs
PublicationAn extension of the re-identification method of modeling objects behavior in muti-camera surveillance systems, related to adding a particle filter to the decision-making algorithm is covered by the paper. A variety of tracking methods related to a single FOV (Field of Vision) are known, proven to be quite different for inter-camera tracking, especially in case of non-overlapping FOVs. The re-identification methods refer to the...
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3-D finite-difference time-domain modelling of ground penetrating radar for identification of rebars in complex reinforced concrete structures
PublicationThis paper presents numerical and experimental investigations to identify reinforcing bars using the ground penetrating radar (GPR) method. A novel element of the paper is the inspection of different arrangements of reinforcement bars. Two particular problems, i.e. detection of few adjacent transverse bars and detection of a longitudinal bar located over or under transverse reinforcement, have been raised. An attention was also...
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The consideration to the dynamic systems parameter identification
PublicationIn this paper, a concept for continuous-time dynamic systems parameter identification using modulating function approach is presented. It refers to linear as well as selected non-linear systems. It shows the possibility of direct application without converting differential equation. In particular cases direct application can decrease the amount of computation in non-linear system identification, which generally requires Fourier...
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Expedited constrained multi-objective aerodynamic shape optimization by means of physics-based surrogates
PublicationIn the paper, computationally efficient constrained multi-objective design optimization of transonic airfoil profiles is considered. Our methodology focuses on fixed-lift design aimed at finding the best possible trade-offs between the two objectives: minimization of the drag coefficient and maximization of the pitching moment. The algorithm presented here exploits the surrogate-based optimization principle, variable-fidelity computational...
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Analysis of Interspike-Intervals for the General Class of Integrate-and-Fire Models with Periodic Drive
PublicationWe study one-dimensional integrate-and-fire models of the general type x˙=F (t, x) and analyze properties of the firing map which iterations recover consecutive spike timings. We impose very week constraints for the regularity of the function F (t, x), e.g. often it suffices to assume that F is continuous. If additionally F is periodic in t, using mathematical study of the displacement sequence of an orientation preserving circle...
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Torsional buckling and post-buckling of columns made of aluminium alloy
PublicationThe paper concerns torsional buckling and the initial post-buckling of axially compressed thin-walled aluminium alloy columns with bisymmetrical cross-section. It is assumed that the column material behaviour is described by the Ramberg–Osgood constitutive equation in non-linear elastic range. The stationary total energy principle is used to derive the governing non-linear differential equation. An approximate solution of the equation...
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Electro-mechanical shear buckling of piezoelectric nanoplate using modified couple stress theory based on simplified first order shear deformation theory
PublicationThis paper studies the electro-mechanical shear buckling analysis of piezoelectric nanoplate using modified couple stress theory with various boundary conditions.In order to be taken electric effects into account, an external electric voltage is applied on the piezoelectric nanoplate. The simplified first order shear deformation theory (S-FSDT) has been employed and the governing differential equations have been obtained using...
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A PAIR OF PERFECTLY CONDUCTING DISKS IN AN EXTERNAL FIELD
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A fast algorithm for computing the flux around non-overlapping disks on the plane
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Thermal self-action effects of acoustic beam in a vibrationally relaxing gas
PublicationThermal self-action of acoustic beam in a molecular gas with excited internal degrees of molecules’ freedom, is studied. This kind of thermal self-action differs from that in a Newtonian fluid. Heating or cooling of a medium takes place due to transfer of internal vibrational energy. Equilibrium and non-equilibrium gases, which may be acoustically active, are considered. A beam in an acoustically active gas is self-focusing unlike...
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Modeling the impact of discretizing rotor angular position on computation of field-oriented current components in high speed electric drives
PublicationModern drives consist of alternating current electric motors, and the field-oriented control (FOC) of such motors enables fast, precise, and robust regulation of a drive's mechanical variables such as torque, speed, and position. The control algorithm, implemented in a microprocessor, requires feedback from motor currents, and the quality of this feedback is essential to a drive's control properties. Motor phase currents are sampled...
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Nuclear Power Plant Steam Turbine - Modeling for Model Based Control Purposes
PublicationThe nature of the processes taking place in a nuclear power plant (NPP) steam turbine is the reason why their modeling is very difficult, especially when the model is intended to be used for on-line optimal model based process control over a wide range of operating conditions, caused by changing electrical power demand e.g. when combined heat and power mode of work is utilized. The paper presents three nonlinear models of NPP steam...
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Solving Boundary Value Problems for Second Order Singularly Perturbed Delay Differential Equations by ε-Approximate Fixed-Point Method
PublicationIn this paper, the boundary value problem for second order singularly perturbed delay differential equation is reduced to a fixed-point problem v = Av with a properly chosen (generally nonlinear) operator A. The unknown fixed-point v is approximated by cubic spline vh defined by its values vi = vh(ti) at grid points ti, i = 0, 1, ... ,N. The necessary for construction the cubic spline and missing the first derivatives at the boundary...
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Study of free convective boundary layer of isothermal lateral surface of axisymmetrical horizontal body
PublicationPrzedstawiono rozwiązanie równań Naviera-Stokesa i Fouriera-Kirchhoffa we współrzędnych tau i sigma. Pierwsza jest styczną a druga normalną do konwekcyjnych linii prądu, wzdłuż jakich porusza się ogrzany od powierzchni płyn. Wynik w postaci równania na grubość warstwy przyściennej zweryfikowano dla granicznych przypadków ciała obrotowego o poziomej osi symetrii (stożka poziomego i kołowej pionowej płyty).
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On the theory and numerical simulation of acoustic and heat modes interaction in a liquid with bubbles: acoustic quasi-solitons
PublicationTeoria rzutowania zaburzenia ogólnego na mody. Zastosowanie metody do badań układu równań typu Korteweg`a-de Vries`a. Rozwiązania analityczne i simulacje numeryczne.
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Extensions of Quasilinearization Method for Differential Equations with Integral Boundary Conditions
PublicationPraca dotyczy równań różniczkowych z warunkami brzegowymi typu całkowego. Podano warunki dostateczne na istnienie jedynego rozwiązania takiego zagadnienia i pokazano, że odpowiednio konstruowane ciągi monotoniczne są zbieżne do tego rozwiązania i jest to zbieżność kwadratowa. Te monotoniczne ciągi są przybliżonymi rozwiązaniami problemu wyjściowego i obustronnie szacują szukane rozwiązanie.
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Problem of proper decomposition and initialization of acoustic and entropy modes in a gas affected by the mass force
PublicationThe relations connecting perturbations specific for acoustic and entropy modes in an accelerated fluid or in a fluid affected by constant mass force, are derived. They allow to decompose the total vector of perturbations and the overall energy into acoustic and non-acoustic parts uniquely at any instant. In order to do this, three quantities are required, for example total perturbations in entropy, pressure and velocity. The evaluations...
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Invariant measures for interval translations and some other piecewise continuous maps
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Book review: Simulation-Driven Design Optimisation and Modelling for Microwave Engineering
PublicationCelem książki jest przedstawienie aktualnego stanu badań dotyczących projektowania układów mikrofalowych poprzez modelowanie i optymalizacje wspomagane symulacjami elektromagnetycznymi. Grupa międzynarodowych ekspertów zajmujących się rożnymi aspektami komputerowo wspomaganego projektowania układów mikrofalowych, podsumowuje i dokonuje przeglądu ostatnich osiągnięć w tej dziedzinie oraz przedstawia szereg praktycznych zastosowań....
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A modelling approach to the transport support for the harvesting and transportation complex under uncertain conditions
PublicationThe article proposes a modelling approach based on structural and parametric identification of the transport support of the harvesting and transportation complex. The efficiency and effectiveness of the proposed methods of structural and parametric identification for the development of a system for harvesting and transportation complex operation has been proved. A mathematical model based on fuzzy logic has been developed. It reflects...
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A comprehensive approach to double inverted pendulum modelling
PublicationThe problem of mathematical modelling and indication of properties of a DIP has been investigated in this paper. The aim of this work is to aggregate the knowledge on a DIP modelling using the Euler-Lagrange formalism in the presence of external forces and friction. To indicate the main properties important for simulation, model parameters identification and control system synthesis, analytical and numerical tools have been used....
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Mode choice modelling for urban areas
PublicationThe article presents the question of mode choice modelling in a four-stage travel modelling process. The article indicates limitations of currently used simplified methods of mode choice modelling and presents the possibility of using a more detailed approach that accounts for additional, statistically significant factors with the use of advanced mathematical tools, discrete choice models. A need has also been identified to include...
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Selected problems of decision making modelling in power engineering
PublicationThe paper presents the selected problems of decision making modelling in power engineering specially investment risk evaluation methods. The proposed model can be used in the range programming the development and investing process in power engineering. Decision making problems in power engineering and the evaluation of investment effectiveness in particular are closely related to modelling which relatively accurately reflects...
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Modelling of blood flow: from macro to microscales
PublicationThe aim of this paper it to review various scale approaches to blood flow modelling. Blood motion may be described by three types of mathematical models according to the observed scales or resolutions, namely microscopic, mesoscopic and macroscopic description. The above approaches are discussed together with their advantages and disadvantages. Several results of mesoscopic simulations are presented.
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Biological processes modelling for MBR systems: A review of the state-of-the-art focusing on SMP and EPS
PublicationA mathematical correlation between biomass kinetic and membrane fouling can improve the understanding and spread of Membrane Bioreactor (MBR) technology, especially in solving the membrane fouling issues. On this behalf, this paper, produced by the International Water Association (IWA) Task Group on Membrane modelling and control, reviews the current state-of-the-art regarding the modelling of kinetic processes of biomass, focusing on...
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A SHORT REVIEW OF BLOOD FLOW MODELLING METHODS: FROM MACRO- TO MICROSCALES
PublicationThe aim of this paper it to review various scale approaches to the blood flow modelling. Blood motion may be described by three types of mathematical models according to the observed scales or resolutions, namely microscopic, mesoscopic and macroscopic descriptions. The above approaches are discussed together with their advantages and disadvantages. Several results of mesoscopic simulations are presented with particular attention...
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The use of mathematical models for diagnosis of activated sludge systems in WWTP
PublicationIn this study diagnosis of activated sludge systems in wastewater treatment plant (WWTP) was investigated. Diagnosis of technical objects can be realized in many ways. One of the divisions of the diagnostic methods include modelling with or without a model of the object. The first of these is the analysis of the symptoms for which, based on the parameter values, the abnormality in the diagnosed objects are sought. Another way is...
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Advances in analysis, quantification and modelling of N2O emission in SBRs under various DO set points
PublicationNitrous oxide (N2O), considered a major greenhouse gas (GHG) in wastewater treatment plants (WWTPs), is produced during both nitrification and denitrification processes; hence, it needs to be controlled by internal and external strategies. Various factors, such as DO, temperature, and pH, could be incorporated into the mitigation of emissions in WWTPs. In this research, potential operational strategies were investigated in order...