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Search results for: semiempirical model
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MARKAL long-term power generation scenarios for Poland - Concept of the model
PublicationIn this paper we have presented the concept of Polish MARKAL optimization model developed for the needs of power generation scenarios in long-term perspective i.e. by 2040. The depiction of Polish MARKAL with Reference Energy System structure was provided. In addition, basic model assumptions, energy technology database, projections of electricity demand and power plant ageing pathways were presented. Our goal is to test MARKAL...
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MODEL CHŁODZENIA ORGANIZMU NOWORODKA DLA UZYSKANIA STANU HIPOTERMII LAGODNEJ
PublicationArtykuł jest kontynuacją cyklu publikacji, które ukazały się w „TCHK” w 2009 roku, a dotyczyły selektywnego chłodzenia mózgu noworodka po niedotlenieniu okołoporodowym. W tym materiale przedstawiono wykonany w programie Matlab – Simulink model symulujący zmiany, jakie zachodzą w organizmie noworodka podczas wprowadzania go w stan hipotermii łagodnej. Model powyższy pomimo dużych uproszczeń odzwierciedla zmiany fizjologiczne w zakresie...
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An application of simulation model of fuel consumption in diagnostic system of wheeled tractors
PublicationAn application of computer controlled fuel injection systems in vehicle engines and growing demands concerning toxic substances emission and fuel consumption was a main reason for OBD (On Board Diagnosis) development. In spite of a great technological development, only some tractors are equipped in diagnostic systems. On board diagnostic is strongly connected with emission demands and does not concern other important vehicle functions. In...
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An Empirical Propagation Model for Mobile Radio Links in Container Terminal Environment
PublicationIn this paper, a novel empirical propagation model for mobile radio links in a container terminal environment is presented. Measurement propagation research carried out in the Deepwater Container Terminal (DCT) in Gdańsk, Poland is described, and the investigated environment is characterized. The results of the statistical evaluation of the new model are discussed. In addition, statistical tuning of the Walfisch–Ikegami model for...
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Model-based testing for execution algorithms in the simulation of cyber-physical systems
PublicationThe understanding of simulation semantics of a hybrid system is a challenge for computational engineers as it requires expertise in computer science, engineering, numerical methods, and mathematics at once. The testing methods for the execution of a simulation are being researched but not yet applied on the industrial level. Consequently, the semantics of the simulation becomes a critical artifact in the system development process....
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Computational Model of Time for Stiff Hybrid Systems Applied to Control Synthesis
PublicationComputational representation.
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Poczucie samoskuteczności a nadmierne zaangażowanie w działaniach przedsiębiorców: Model teoretyczny
PublicationArtykuł przedstawia model teoretyczny wyjaśniający wpływ poczucia samoskuteczności na eskalację zaangażowania wśród przedsiębiorców. Autorzy postulują, że rozbieżność pomiędzy poziomem przekonań dotyczących własnej skuteczności a faktyczną skutecznością tworzy lukę skuteczności. Początkujący przedsiębiorcy w związku z ich niewielkim doświadczniem są szczególnie narażeni na ryzyko eskalacji zaangażowania, gdyż cechują się ograniczonymi...
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Development of the System Assurance Reference Model for Generating Modular Assurance Cases
PublicationAssurance cases are structured arguments used to demonstrate specific system properties such as safety or security. They are used in many industrial sectors including automotive, aviation and medical devices. Larger assurance cases are usually divided into modules to manage the complexity and distribute the work. Each of the modules is developed to address specific goals allocated to the specific objects i.e. components of the...
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A Robust Random Forest Model for Classifying the Severity of Partial Discharges in Dielectrics
PublicationPartial Discharges (PDs) are a common source of degradation in electrical assets. It is essential that the extent of the deterioration level of insulating medium is correctly identified, to optimize maintenance schedules and prevent abrupt power outages. Temporal PD signals received from damaged insulation, collected through the IEC-60270 method is the gold standard for PD detection. Temporal signals may be transformed to the frequency...
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A Formal Approach to Model the Expansion of Natural Events: The Case of Infectious Diseases
PublicationA formal approach to modeling the expansion of natural events is presented in this paper. Since the mathematical, statistical or computational methods used are not relevant for development, a modular framework is carried out that guides from the external observation down to the innermost level of the variables that have to appear in the future mathematical-computational formalization. As an example we analyze the expansion of Covid-19....
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TRAVELLING WAVES FOR LOW–GRADE GLIOMA GROWTH AND RESPONSE TO A CHEMOTHERAPY MODEL
PublicationLow-grade gliomas (LGGs) are primary brain tumours which evolve very slowly in time, but inevitably cause patient death. In this paper, we consider a PDE version of the previously proposed ODE model that describes the changes in the densities of functionally alive LGGs cells and cells that are irreversibly damaged by chemotherapy treatment. Besides the basic mathematical properties of the model, we study the possibility of the...
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Bimodal deep learning model for subjectively enhanced emotion classification in films
PublicationThis research delves into the concept of color grading in film, focusing on how color influences the emotional response of the audience. The study commenced by recalling state-of-the-art works that process audio-video signals and associated emotions by machine learning. Then, assumptions of subjective tests for refining and validating an emotion model for assigning specific emotional labels to selected film excerpts were presented....
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A Comprehensive Review: Applications of the Kozeny–Carman Model in Engineering with Permeability Dynamics
PublicationIn this review article, we investigate the dynamic nature of the Kozeny–Carman Model concerning permeability and its application in engineering contexts. Providing insights into the changing dynamics of permeability within mining, petroleum, and geotechnical engineering, among other engineering applications. While some are complex and require additional modifcations to be applicable, others are simple and still function in specifc...
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A NUMERICAL STUDY ON THE DYNAMICS OF DENGUE DISEASE MODEL WITH FRACTIONAL PIECEWISE DERIVATIVE
PublicationThe aim of this paper is to study the dynamics of Dengue disease model using a novel piecewise derivative approach in the sense of singular and non-singular kernels. The singular kernel operator is in the sense of Caputo, whereas the non-singular kernel operator is the Atangana–Baleanu Caputo operator. The existence and uniqueness of a solution with piecewise derivative are examined for the aforementioned problem. The suggested...
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Numerical Model of the Aortic Valve Implanted Within Real Human Aorta
PublicationCardiovascular system diseases are the main cause of deaths in developed and developing countries. The main reasons are myocardial infarction, heart failure, stroke and valvular diseases. These are caused mainly by arteriosclerosis. The valvular diseases involve a significant burden for the health care system and their frequency is rising with the patient age. This work describes the tools and numerical models appropriate for modeling...
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E-Estonia as a role model? Some general considerations and applicability in France
PublicationEstonia has recently been widely recognised – in the policy circles, academia, as well as the media space – as one of the more advanced nation states when it comes to digital government (and governance) transformation (e.g. Margetts and Naumann, 2017; Heller, 2017). Ever greater attention Estonia attracted with the two most recent digital government initiatives, namely the e-Residency and the virtual data embassy, both first of...
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A hierarchical observer for a non-linear uncertain CSTR model of biochemical processes
PublicationThe problem of estimation of unmeasured state variables and unknown reaction kinetic functions for selected biochemical processes modelled as a continuous stirred tank reactor is addressed in this paper. In particular, a new hierarchical (sequential) state observer is derived to generate stable and robust estimates of the state variables and kinetic functions. The developed hierarchical observer uses an adjusted asymptotic observer...
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Analysis of dynamics of a map-based neuron model via Lorenz maps
PublicationModeling nerve cells can facilitate formulating hypotheses about their real behavior and improve understanding of their functioning. In this paper, we study a discrete neuron model introduced by Courbage et al. [Chaos 17, 043109 (2007)], where the originally piecewise linear function defining voltage dynamics is replaced by a cubic polynomial, with an additional parameter responsible for varying the slope. Showing that on a large...
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Neural network model of ship magnetic signature for different measurement depths
PublicationThis paper presents the development of a model of a corvette-type ship’s magnetic signature using an artificial neural network (ANN). The capabilities of ANNs to learn complex relationships between the vessel’s characteristics and the magnetic field at different depths are proposed as an alternative to a multi-dipole model. A training dataset, consisting of signatures prepared in finite element method (FEM) environment Simulia...
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Model szyny integracyjnej danych i ontologii procesów Smart Cities
PublicationW artykule przedstawiono propozycję modelu szyny integracyjnej wykorzystywanego w projektowaniu architektur systemów Smart Cities. Model takiej szyny staje się niezbędny przy projektowaniu architektur wysokopoziomowych (ang. high level architecture), w ramach których procesy silosowe organizacji powinny być widziane z pespektywy jej ontologii. Aby taka szyna mogła być wykorzystywana przez dowolne miasta zaproponowano rozwiązanie...
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Simulation Model of IMS/NGN with Transport Stratum Based on MPLS Technology
PublicationIn the paper we continue our research on traffic modelling in the Next Generation Network (NGN) architecture, which includes the IP Multimedia Subsystem (IMS) elements. A simulation model of a single NGN domain with transport stratum based on the Multiprotocol Label Switching (MPLS) technology is proposed, which allows evaluation of mean response time of this stratum. The simulation model is applied to verify the results obtained...
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An Off-Body Channel Model for Body Area Networks in Indoor Environments
PublicationThis paper presents an off-body channel model for body area networks (BANs) in indoor environments. The proposed model, which is based on both simulations and measurements in a realistic environment, consists of three components: mean path loss, body shadowing, and multipath fading. Seven scenarios in a realistic indoor office environment containing typical scatterers have been measured: five were static (three standing and two...
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The Reference Model of Tools Adaptation in the Perspective of Technological Agile Transformaton in IT Organizations
PublicationThe scientific aim of the presented paper is the analysis of agile transformation processes in IT organizations in technological perspective of such transformation. The phenomenon of agile transformation becomes a complex challenge for an IT organization, since it has not been analysed in detail so far. There is not any research on the readiness of IT organizations for the realization of agile transformation processes, and such...
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International Competitiveness of Czech Manufacturing: A Sectoral Approach with Error Correction Model
PublicationThe main objective of this paper is to find the determinants of the international competitiveness of the manufacturing sectors of the Czech economy, using the database of 13 manufacturing subsectors in 1995–2011, with the aid of ECM model. The authors research the question of how much foreign and domestic demand, the level of labour costs, the level of sector innovation intensity, the level of sector openness to foreign markets...
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Proportional-Derivative and Model-Based Controllers for Control of a Variable Mass Manipulator
PublicationIn the paper, numerical analysis of dynamics of a variable mass manipulator is presented. A revolute joints composed manipulator is considered. Payload of the gripper is considered as the only element characterized by unknown value of its mass (variable between subsequent operations). As in other cases of the revolute joints composed manipulators, its behaviour dependents significantly on the pose of the manipulator. When the manipulator...
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Multi-Option Model of Railway Traffic Organization Including the Energy Recuperation
PublicationThe article presents the issue of organization of railway traffic within the station, taking into account energy recuperation. We identified a number of factors which affect the energy efficiency of recuperation, including the issue of transfer of energy technology between a few vehicles. We presented some aspects of the decision problem of graphic train timetable construction with regard to recuperation. As an indicator of quality...
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Efficient analysis of structures with rotatable elements using model order reduction
PublicationThis paper presents a novel full-wave technique which allows for a fast 3D finite element analysis of waveguide structures containing rotatable tuning elements of arbitrary shapes. Rotation of these elements changes the resonant frequencies of the structure, which can be used in the tuning process to obtain the S-characteristics desired for the device. For fast commutations of the response as the tuning elements are rotated, the...
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Novel Analytic-Numerical Model of Free Convection: with Leading Edge Considered
PublicationA novel solution of the free convection boundary problem is represented in analytical form for velocity and temperature for an isothermal vertical plate, as an example. These fields are built as a Taylor Series in the x coordinate with coefficients as functions of the vertical coordinate (y). We restrict ourselves by cubic approximation for both functions. The basic Navier-Stokes and Fourier-Kirchhoff equations and boundary conditions...
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Nitrogen mass balance and mathematical model of a Structured- Bed Reactor (SBRRIA)
PublicationAn up-flow structured-bed reactor subjected to recirculation and intermittent aeration (SBRRIA) was operated under varying influent conditions. The influent COD/N ratio was adjusted by maintaining a stable organic loading rate (average of 1.07 kgCOD m-3 d-1) and changing the nitrogen loading rate from 0.1 to 0.4 kg N m-3. Therefore, three different COD/N ratios were tested: 9.7±1 (Scenario 1); 7.6±1 (Scenario 2) and 2.9±1 (Scenario...
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MODEL OCZYSZCZALNI ŚCIEKÓW JAKO NARZĘDZIE DO OPTYMALIZACJI PROCESÓW BIOLOGICZNYCH
PublicationW artykule pokazano przykład zastosowania modelu oczyszczalni ścieków jako narzędzia do optymalizacji pracy oczyszczalni. W tym celu dla przykładowej oczyszczalni ścieków opracowano model komputerowy, który następnie poddano symulacji dynamicznej. W artykule opisano wyniki symulacji dla systemu trójfazowego w procesie Bardenpho, uzupełnionym komorą predenitryfikacji (układ zbli- żony do JHB). Model komputerowy oczyszczalni ścieków...
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Proportional-derivative and Model-based Controllers for Control of a Variable Mass Manipulator
PublicationW artykule prezentowano wyniki analiza numeryczna dynamiki manipulatora o zmiennej masie. W skład manipulatora wchodzą jedynie członu i przeguby obrotowe. Ładowność chwytaka jest traktowana jako jedyny element o zmiennej masie. Podobnie jak w przypadku innych manipulatorów wyposażonych w przeguby obrotowe, parametry jego dynamika zależą od aktualnego ustawienia. Gdy przemieszczenia obejmują większy zakres roboczy, w równaniach...
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A simplified behavioral MOSFET model based on parameters extraction for circuit simulations.
PublicationThe paper presents results on behavior modeling of general purpose Metal-Oxide Semiconductor Field-Effect Transistor (MOSFET) for simulation of power electronics systems requiring accuracy both in steady-state and in switching conditions. Methods of parameters extraction including nonlinearity of parasitic capacitances and steady-state characteristics are based on manufacturer data sheet and externally measurable characteristics....
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Model dwuwirnikowej maszyny indukcyjnej w aspekcie elektromagnetycznego mechanizmu różnicowego
PublicationW referacie przedstawiono obwodowy model maszyny indukcyjnej z dwoma wirnikami, który proponowany jest w koncepcji elektromagnetycznego mechanizmu różnicowego. Koncepcja ta przewiduje zastosowanie dwuwirnikowej maszyny elektrycznej spełniającej jednocześnie funkcje mechanizmu różnicowego oraz napędu pojazdu samochodowego. W realizacji tej koncepcji niezbędna jest także przekładnia mechaniczna sprzężona z jednym z wałów silnika....
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Developing a model of cooperation between universities and business - the generalization of cases of cooperation
PublicationThe aim of this paper is to present a model of cooperation between universities and business.
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Soft- and hard-decision multiple-model estimators for air traffic control
PublicationAnalizuje się problem śledzenia samolotów cywilnych manewrowania w zapewnianiu kontroli ruchu lotniczego (ATC) systemów za pomocą wielomodelowej (MM) estymacji stanu. Budując odpowiedni zestaw modeli manewrowania można opisać, jak różne manewry wpływają na proces oceny stanu wykonywany przez filtr Kalmana (KF) w oparciu o model ruchu bezmanerwowego. Metodologia ta prowadzi do podsystemu diagnostycznego, który wspiera estymator...
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Polyarmonic model of synchronous generator for analysis of autonomous power generation systems
PublicationAbstract: This paper presents the polyharmonic modelling of synchronous generator (SG) in machine variables. The simple geometry and windings physical layout has been used for inductance calculations of a salient-pole SG. The main advantage of this model is the ease of describing an autonomous power generation system (APGS) in terms of its topology and thus providing effective analysis at the static and dynamic states, both for...
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Verification of geotechnical numerical simulations by model tests using PIV technique
PublicationPrzedstawiono metodykę i wyniki badań modelowych stateczności fundamentów bezpośrednich posadowionych w sąsiedztwie kątowych ścian oporowych. Dla takiego złożonego układu fundament - obciążenie - podłoże gruntowe wykonano badania modelowe w płaskim stanie odkształcenia na gruncie naturalnym i analogowym. Trajektorie i izopola przemieszczeń oraz progresywny rozwój kształtu i zasięgu powierzchni poślizgu określono techniką PIV.
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Minimal parameter implicit solvent model for ab initioelectronic-structure calculations
PublicationAbstract - We present an implicit solvent model for ab initio electronic-structure calculations which is fully self-consistent and is based on direct solution of the nonhomogeneous Poisson equation. The solute cavity is naturally defined in terms of an isosurface of the electronic density according to the formula of Fattebert and Gygi (J. Comput. Chem., 23 (2002) 662). While this model depends on only two parameters, we demonstrate...
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An Approach to Mean Path Loss Model Estimation for Off-Body Channels
PublicationThis paper presents an approach to estimation of the mean path loss model parameters in off-body Body Area Networks channels. In this approach, the path loss exponent is constrained to a value obtained for the line-of-sight (LoS) propagation in the co-polarised channel, considering a generalised static scenario. The comparison of the goodness of fit between the proposed approach and other approaches, for a set of measurements obtained...
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Geometry Parametric Model Order Reduction with Randomly Generated Projection Bases
PublicationIn this work, a reduced-order model for geometry parameters and fast frequency sweep is proposed. The Finite Element Method is used to solve time-harmonic Maxwell’s equations. Taking into account the electromagnetic field does not arbitrarily vary as a function of frequency and geometry parameters, a low dimension system manifold is identified. Thus, the original Finite Element problem can be approximated by a model of reduced...
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Diagnosis of Damage in a Steel Tank Model by Shaking Table Harmonic Tests
PublicationDiagnosis of damage in civil engineering structures has recently become an important issue in the safety assessment procedure. Among a number of different approaches, a method of measuring the changes in natural frequencies is one of the most effective indicators of global damage. It has been successfully applied to relatively small. structures, however, the tests on large structures are very difficult and the practical application...
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On the influence of shell element properties on the response of car model in crash test
PublicationIt goes without saying that numerical simulations play important role in the modern engineering practice. Contemporary CAD environments combined with FEM solvers, along with computer power of modern processors, give the engineer fast and efficient tool. Ultimately, however it is the user alone who is responsible for the correctness of the results. As long as the FEM calculations remain in the sphere of academic exercise, the inevitable...
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Simplified, multiregional fuzzy model of a nuclear power plant steam turbine
PublicationPower systems, including steam turbines and synchronous generators, are complex nonlinear systems with parameters varying over time. The paper presents the developed simplified, multiregional fuzzy model of the steam turbine of a nuclear power plant turbine generator set and compares the results with a full nonlinear model and commonly used linear input-output model of a steam turbine. The proposed model consist of series of linear...
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Membrane model of human abdominal wall. Simulations vs. in vivo measurements
PublicationThe study presents a methodology of defining a numerical model of human abdominal wall based on the experimentally registered data of the abdomen geometry due to variations of the intraabdominal pressure. The abdominal wall is modelled here as a simple homogeneous membrane structure made of linear orthotropic material The displacements registered during the increase of pressure are compared with the re-sults of the model static...
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Global sensitivity analysis of membrane model of abdominal wall with surgical mesh
PublicationThe paper addresses the issue of ventral hernia repair. Finite Element simulations can be helpful in the optimization of hernia parameters. A membrane abdominal wall model is proposed in two variants: a healthy one and including hernia defect repaired by implant. The models include many uncertainties, e.g. due to variability of abdominal wall, intraabdominal pressure value etc. Measuring mechanical properties with high accuracy...
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Integration of a Multilevel Transport System Model into Sustainable Urban Mobility Planning
PublicationWhen planning their transport policy, cities usually focus on developing sustainable transport systems and reducing the negative consequences of transport. One way to deliver transport policies is to use the Sustainable Urban Mobility Plan (SUMP), a strategic document designed to meet the demand for mobility whilst ensuring adequate quality of life for the residents. The process of Sustainable Urban Mobility Planning (SUMP process)...
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From a Point Cloud to a 3D Model - an Exercise for Users of AutoCAD and Revit
PublicationThe paper presents a proposal of the topic of an exercise for students of building faculties as part of classes on 3D modelling. The task consists in creating a three-dimensional model based on the measurement obtained with the Leica P30 laser scanner. Due to the maximum number of points in the cloud in the presented programs, the output files must be properly cleared and reduced. The point cloud was pre-processed in Cyclone software....
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Mathematical analysis of a generalised p53-Mdm2 protein gene expression model
PublicationWe propose the generalisation of the p53-Mdm2 protein gene expression model introduced by Monk (2003). We investigate the stability of a unique positive steady state and formulate conditions which guarantee the occurrence of the Hopf bifurcation. We show that oscillatory behaviour can be caused not only by time lag in protein transcription process, but also can be present in the model without time delay. Moreover, we investigate...
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Investigation method and mathematical model of pressure losses in hydraulic rotary motor
PublicationTis paper presents a way of determining the coefcient k of the pressure losses Δp (fow drag) in internal ducts 8 Mp of SWSB-63 hydraulic motor. Te coefcient is determined at a fow rate equal to the theoretical capacity Q of the Pt pump feeding the motor , the losses are related to the nominal pressure p in the hydraulic system. Te investigations n followed a model of energy performance of hydraulic rotary motor, proposed by...
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APPLICATION OF VORTEX FLOW MODEL IN PROPELLER-STATOR SYSTEM DESIGN AND ANALYSIS
PublicationThe paper covers basics of the vortex model used for propeller-stator systems. The outline of the design algorithm is given and the results of its application are shown. The designed propeller-stator system was the subject of model tests run at the CTO model basin and cavitation tunnel. Stator’s influence on the delivered power required by the propeller and its revolution rate has been examined by conducting self-propulsion...