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Wyniki wyszukiwania dla: LOGIC DIFFERENTIAL CALCULUS
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Regularity of weak solutions for aclass of elliptic PDEs in Orlicz-Sobolev spaces
PublikacjaWe consider the elliptic partial differential equation in the divergence form $$-\div(\nabla G(\nabla u(x))) t + F_u (x, u(x)) = 0,$$ where $G$ is a convex, anisotropic function satisfying certain growth and ellipticity conditions We prove that weak solutions in $W^{1,G}$ are in fact of class $W^{2,2}_{loc}\cap W^{1,\infty}_{loc}$.
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Distortional buckling of thin-walled columns of closed quadratic cross-section
PublikacjaThe elastic stability of axially compressed column related to the cross-section distortion is investigated. Two kinds of closed quadratic cross-sections are taken into consideration with internal walls and without it. The governing differential equation is derived with aid of the principle of stationary total potential energy. The critical loads for the simply supported columns are found in an analytical form and compared with...
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Application of the J-matrix method to multichannel scattering
PublikacjaIn this contribution we describe the multichannel extension to the nonrelativistic J-matrix method, and present differential cross sections for scattering of slow electrons from Argon atoms. Nonrelativistic phase shifts, then the S-matrix and the cross sections have been calculated using newly developed Fortran code, JMATRIX-MULTI.We applied the model Hartree-Fock potential as the scattering potential, which was truncated in the...
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Metody redukcji zróżnicowania materiałów wejściowych w warunkach wysokiej różnorodności produktów gotowych
PublikacjaArtykuł opisuje zagadnienie związane z negatywnym wpływem wysokiego zróżnicowania materiałów wejściowych w procesach produkcyjnych o wysokiej różnorodności produktów gotowych. W pierwszej części pracy opisane zostało oddziaływanie zróżnicowania materiału na podstawowe mierniki skuteczności procesu produkcyjnego z uwzględnieniem cen zakupu materiałów, kosztów utrzymania zapasów, jakości produktu oraz wydajności maszyn i urządzeń....
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Zdolności dynamiczne do budowania chmury wartości w modelach biznesów
PublikacjaObserwacja współczesnych metod tworzenia wartości daje podstawy do wyłonienia nowej logiki ich generowania. Analiza modeli wytwarzania wartości przez przedsiębiorstwa np. sieciowe wykazała, że formułują one chmury wartości. Struktury tych chmur są różnorodne, niejednolite, kłębiaste. Przeprowadzone prace pozwoliły na sformułowanie obrazów wartości generowanych przez twarde komponenty modeli biznesów. Osiągnięcie tych wyników pozwoliło...
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Krzywa przejściowa z wygładzoną krzywizną dla dróg kolejowych
PublikacjaW pracy przedstawiono koncepcję nowej postaci krzywej przejściowej, o liniowym przebiegu krzywizny na długości i wygładzonymi rejonami skrajnymi. Może ona stanowić alternatywę dla tzw. gładkich krzywych przejściowych, o nieliniowym przebiegu krzywizny na całej długości. Została tutaj wykorzystana uniwersalna metoda identyfikacji krzywych przejściowych za pomocą równań różniczkowych. Wyznaczono ogólne równania krzywizny oraz odpowiednie...
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Inverse Flood Routing Using Simplified Flow Equations
PublikacjaThe paper considers the problem of inverse flood routing in reservoir operation strategy. The aim of the work is to investigate the possibility of determining the hydrograph at the upstream end based on the hydrograph required at the downstream end using simplified open channel flow models. To accomplish this, the linear kinematic wave equation, the diffusive wave equation and the linear Muskingum equation are considered. To achieve...
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A new approach to determination of the two-mass model parameters of railway current collector
PublikacjaThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
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A new approach to determination of the two-mass model parameters of railway current collector
PublikacjaThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
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Correlation–polarization effects in electron/positron scattering from acetylene: A comparison of computational models
PublikacjaDifferent computational methods are employed to evaluate elastic (rotationally summed) integral and differential cross sections for low energy (below about 10 eV) positron scattering off gas-phase C2H2 molecules. The computations are carried out at the static and static-plus-polarization levels for describing the interaction forces and the correlation–polarization contributions are found to be an essential component for the correct...
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Comparison of the paracetamol electrochemical determination using boron-doped diamond electrode and boron-doped carbon nanowalls
PublikacjaTwo different type of electrodes, boron-doped diamond electrode (BDD) and boron-doped carbon nanowalls (B:CNW) electrode, were used for the electrochemical determination of paracetamol using the cyclic voltammetry and the differential pulse voltammetry in phosphate buffered saline, pH = 7.0. The main advantage of these electrodes is their utilization without any additional modification of the electrode surface. The peak current...
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Optymalizacja zasobów chmury obliczeniowej z wykorzystaniem inteligentnych agentów w zdalnym nauczaniu
PublikacjaRozprawa dotyczy optymalizacji zasobów chmury obliczeniowej, w której zastosowano inteligentne agenty w zdalnym nauczaniu. Zagadnienie jest istotne w edukacji, gdzie wykorzystuje się nowoczesne technologie, takie jak Internet Rzeczy, rozszerzoną i wirtualną rzeczywistość oraz deep learning w środowisku chmury obliczeniowej. Zagadnienie jest istotne również w sytuacji, gdy pandemia wymusza stosowanie zdalnego nauczania na dużą skalę...
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SLIDING MODE-PID FUZZY CONTROLLER WITH A NEW REACHING MODE FOR UNDERWATER ROBOTIC MANIPULATORS
PublikacjaDesign of an accurate and robust controller is a challenging topic in an underwater manipulator control. This is due to hydrodynamic disturbances in underwater environment. In this paper a sliding mode control (SMC) included a PID sliding surface and fuzzy tunable gain is designed. In this proposed controller robustness property of SMC and fast response of PID are incorporated with fuzzy rules to reduce error tracking. In the...
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Quality measure of VoIP services in carrier grade systems
PublikacjaThis paper describes passive measurement method of VoIP services quality in carrier grade systems, engaging slight system resources. Measurement is based on analyzing quality information in sender and receiver reports in RTCP packets sent by the end points of RTP session. Data is analyzed and stored by Session Boarder Controllers SBC. Objective evaluation of VoIP calls is based on quality information of IP connection and voice...
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The Factors Affecting Group Identity of Cluster Structures
PublikacjaThe paper provides a new approach to cluster analysis, basing on a sociologically rooted concept of identity. The authors state that identity in cluster structures is formed by two main groups of factors – uncontrollable or slightly controllable factors (identity mix) and factors that can be fully controlled by a cluster initiative (corporate identity mix). It means that the cluster coordinator is able to consciously build the...
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Behavior Analysis and Dynamic Crowd Management in Video Surveillance System
PublikacjaA concept and practical implementation of a crowd management system which acquires input data by the set of monitoring cameras is presented. Two leading threads are considered. First concerns the crowd behavior analysis. Second thread focuses on detection of a hold-ups in the doorway. The optical flow combined with soft computing methods (neural network) is employed to evaluate the type of crowd behavior, and fuzzy logic aids detection...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublikacjaThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublikacjaThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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Distorsional analysis of I-section beam
PublikacjaAn elastic stiffness matrix was derived in the case of distortion of a restrained thin-walled I-section beam using the minimum total stationary elastic energy condition. The function describing the angle of distortion was adopted form the solution of differential equation in the case of restrained distortion. The example presented in the paper helps to assess the correctness of the proposed solution. The proposed elastic stiffness...
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Dynamics of a simplified HPT model in relation to 24h TSH profiles
PublikacjaWe propose a simplified mathematical model of the hypothalamus-pituitary-thyroid (HPT) axis in an endocrine system. The considered model is a modification of the model proposed by Mukhopadhyay and Bhattacharyya in [10]. Our system of delay differential equations reconstructs the HPT axis in relation to 24h profiles of human in physiological conditions. Homeostatic control of the thyroid-pituitary axis is considered by using...
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Fractional Problems with Right-Handed Riemann-Liouville Fractional Derivatives
PublikacjaIn this paper, we investigate the existence of solutions for advanced fractional differential equations containing the right-handed Riemann-Liouville fractional derivative both with nonlinear boundary conditions and also with initial conditions given at the end point T of interval [0,T ]. We use both the method of successive approximations, the Banach fixed point theorem and the monotone iterative technique, as well. Linear problems...
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Implementacja w FPGA algorytmu detekcji krawędzi obrazu w czasie rzeczywistym
PublikacjaW artykule przedstawiono projekt architektury oraz implementację układową toru przetwarzania wstępnego obrazu z modułem detekcji krawędzi. Układ został zaimplementowany w FPGA Intel Cyclone. Zrealizowany moduł wykorzystuje pięć wybranych algorytmów wykrywania krawędzi, w tym Robertsa, Sobela i Prewitt.
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Parameter and delay estimation of linear continuous-time systems
PublikacjaIn this paper the problem of on-line identification of non-stationary delay systems is considered. Dynamics of supervised industrial processes is described by ordinary differential equations. Discrete-time mechanization of their continuous-time representations is based on dedicated finite-horizon integrating filters. Least-squares and instrumental variable procedures implemented in recursive forms are applied for simultaneous identification...
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Low energy elastic electron scattering from benzonitrile (C6H5CN)
PublikacjaWe present experimental differential elastic scattering cross sections (DCSs) for low energy electron scattering from benzonitrile along with integral and momentum-transfer cross sections that are determined from these DCSs. The measurements of DCSs are obtained using the relative flow method with helium as the standard gas, in a crossed electron-molecular gas beam arrangement. Our measurements are made at incident electron energies...
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Knowledge base views
PublikacjaThe paper introduces an extension to the NeeK language. In the current shape NeeK allows for selection of fragments of a given ontology. The selected part is automatically mapped to a database schema by Data Views implementation. Experience with a real system using Data Views has shown that the resulting database schema does not necessarily reflect the needs of the business logic of an application that uses a specific Data View....
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Comparison of the effectiveness of automatic EEG signal class separation algorithms
PublikacjaIn this paper, an algorithm for automatic brain activity class identification of EEG (electroencephalographic) signals is presented. EEG signals are gathered from seventeen subjects performing one of the three tasks: resting, watching a music video and playing a simple logic game. The methodology applied consists of several steps, namely: signal acquisition, signal processing utilizing z-score normalization, parametrization and...
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THE AGRI-HOOD AND SLOW-SUBURB CONCEPT IN THE CONTEXT OF AN IN-BETWEEN CITY (ZWISCHENSTADT)
PublikacjaThe concept of an “in-between-city” (Zwischenstadt) interprets the urban sprawl in Europe as a new, evolving model of urban development, taking the form of urbanized landscapes, which does not correspond with the traditional understanding of urban design. The actual shape of an in-between-city reflects the today’s technology and economy generating new lifestyles: global trends coexist with the locality in a strong relation. The...
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A novel luminescent chemical sensor for the determination of Pb 2+ and Cu 2+ ions
PublikacjaSilica xerogel surface grafted with aminopropyl (PrNH2) groups was additionally treated by cetyltrimethylammonium bromide (CTAB) surfactant and ascorbic acid (asc) in alkaline solution. This material symbolized as SiO2-PrNH2-CTAB/asc, proved to be a stable luminescent material, exhibited an emission band peaked at 393 nm under excitation wavelength 335 nm. Time evolution of the band intensity suggests changes of defect concentration...
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On the convergence of a finite-difference discretization à la Mickens of the generalized Burgers–Huxley equation
PublikacjaIn this note, we establish the property of convergence for a finite-difference discretization of a diffusive partial differential equation with generalized Burgers convective law and generalized Hodgkin–Huxley reaction. The numerical method was previously investigated in the literature and, amongst other features of interest, it is a fast and nonlinear technique that is capable of preserving positivity, boundedness and monotonicity....
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Parameter and delay estimation of linear continuous-time systems
PublikacjaIn this paper the problem of on-line identification of non-stationary delay systems is considered. Dynamics of supervised industrial processes is usually described by ordinary differential equations. Discrete-time mechanization of their continuous-time representations is based on dedicated finite-horizon integrating filters. Least-squares and instrumental variable procedures implemented in recursive forms are applied for simultaneous...
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System of wireless magnetic sensors for detection and identification of ferromagnetic vehicles
PublikacjaThe paper presents the results of deformation of the Earth's magnetic field by land vehicles. Basing on the analysis of the shape of the magnetic field deformation, it is possible to detect and identify a vehicle. In order to eliminate the interference of the Earth's magnetic field by the environment, the measurements were performed in a differential configuration. Under a development project a wireless system of magnetic sensors...
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Integrable zero-range potentials in a plane
PublikacjaWe examine general statements in the Wronskian representation of Darboux transformations for plane zero-range potentials. Such expressions naturally contain scattering problem solution. We also apply Abel theorem to Wronskians for differential equations and link it to chain equations for Darboux transforms to fix conditions for further development of the underlying distribution concept. Moutard transformations give a convenient...
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Analytical method of modelling the geometric system of communication route
PublikacjaThe paper presents a new analytical approach to modelling the curvature of a communication route by making use of differential equations. The method makes it possible to identify both linear and nonlinear curvature. It enables us to join curves of the same or opposite signs of curvature. Solutions of problems for linear change of curvature and selected variants of nonlinear curvature in polynomial and trigonometric form were analyzed....
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On–line Parameter and Delay Estimation of Continuous–Time Dynamic Systems
PublikacjaThe problem of on-line identification of non-stationary delay systems is considered. The dynamics of supervised industrial processes are usually modeled by ordinary differential equations. Discrete-time mechanizations of continuous-time process models are implemented with the use of dedicated finite-horizon integrating filters. Least-squares and instrumental variable procedures mechanized in recursive forms are applied for simultaneous...
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Application of the distributed transfer function method and the rigid finite element method for modelling of 2-D and 3-D systems
PublikacjaIn the paper application of the Distributed Transfer Function Method and the Rigid Finite Element Method for modelling of 2-D and 3-D systems is presented. In this method an elastic body is divided into 1-D distributed parameter elements (strips or prisms). The whole body (divided into strips or prism) is described by a set of coupled partial differential equations. Solving this equations in the state space form it is possible...
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Determination of Antioxidant Activity of Vitamin C by Voltammetric Methods
PublikacjaVoltammetric methods—cyclic (CV) and differential pulse voltammetry (DPV) are considered the most appropriate way to evaluate antioxidant activity of redox active compounds. They provide information about both mechanism and kinetics of electrochemical oxidation of antioxidants as well as their physical and chemical properties such as the redox potential or the number of electrons transferred. These methods are helpful for understanding...
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Formation of intermetallic compounds in the solid-liquid composites of the Ga-Ni system
PublikacjaThe processes of formation of intermetallic compounds in the composite system of liquid gallium-nickel powder by the methods of x-ray diffraction, scanning electron microscopy and differential thermal analysis have been studied. A change in the phase composition was discovered and the influence of thermal treatment of the composites under investigation on the phase formation processes was analyzed. The mechanism of gallium enriched...
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Analysis of a gene expression model
PublikacjaWe study a mathematical model of gene transcription and protein synthesis with negative feedback. We consider a system of equations taking into account the number of active binding sites, the way in which dimers bind to DNA and time delay in translation process. For a simplified model that consist of three ordinary differential equations with time delay we derive conditions for stability of the positive steady state and for the...
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Local buckling and initial post-buckling behaviour of channel member flange - analytical approach
PublikacjaThe local buckling and initial post-buckling behaviour of the cold-formed channel member flange is investigated. The governing nonlinear differential equation for axially compressed columns and beams undergoing pure bending is derived using the stationary total potential energy principle. The critical stress and initial post-buckling equilibrium path is determined by means of a perturbation approach. The results obtained allow...
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Regulator przepływu
PublikacjaW artykule opisano konstrukcję i wyniki badań prototypu regulatora przepływu charakteryzującego się brakiem sprężyny. W regulatorze zawór różnicowy zastąpiono zaworem stosunku ciśnień. Charakterystyki przepływowe regulatora mają przebieg niezależny od obciążenia. Nastawa regulatora odbywa się poprzez obrót hydrostatycznie odciążonej tulei dławiącej, wewnątrz której umieszczony jest suwak główny i suwak pomocniczy zaworu stosunku...
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Joint experimental and theoretical study on electron scattering from titanium tetrachloride (TiCl4) molecule
PublikacjaAbsolute grand-total cross section for electron scattering from titanium tetrachloride, TiCl4, molecule was measured at electron-impact energies ranging from 0.3 to 300 eV, in the linear electron-transmission experiment. The elastic integral, differential, momentum transfer, and total ionization cross sections for TiCl4 molecule were also calculated for low and intermediate collisional energies at the level of various theories. The...
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Biowaste chicken eggshell powder as a potential cure modifier for epoxy/anhydride systems: competitiveness with terpolymer-modified calcium carbonate at low loading levels
PublikacjaBiowaste chicken eggshell (ES) powder was applied as a potential cure modifier in epoxy/anhydride systems. Cure behaviour and kinetics of composites filled with very low content (0.1 wt% based on epoxy resin) of ES, calcium carbonate (CaCO3), and terpolymer-modified fillers, mES and mCaCO3, were discussed comparatively. Surface analysis was performed by X-ray photoelectron spectroscopy. Cure kinetics was investigated by differential...
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Chosen aspects of muscle biomechanics
PublikacjaConsidering a striated skeletal muscle as a different properties mechanical system, one can understand series of important phenomena happening in a real muscle phenomenon of muscle: 1) force delivery to skeletal apparatus through tendons; 2) changing of exerted muscle belly mass distribution with regards to skeletal apparatus; 3) beginning drop of muscle force. A disregard of first phenomenon causes an impossibility to explain...
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Numerical solution analysis of fractional point kinetics and heat exchange in nuclear reactor
PublikacjaThe paper presents the neutron point kinetics and heat exchange models for the nuclear reactor. The models consist of a nonlinear system of fractional ordinary differential and algebraic equations. Two numerical algorithms are used to solve them. The first algorithm is application of discrete Grünwald-Letnikov definition of the fractional derivative in the model. The second involves building an analog scheme in the FOMCON Toolbox...
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Homoclinic and Heteroclinic Orbits for a Class of Singular Planar Newtonian Systems
PublikacjaThe study of existence and multiplicity of solutions of differential equations possessing a variational nature is a problem of great meaning since most of them derives from mechanics and physics. In particular, this relates to Hamiltonian systems including Newtonian ones. During the past thirty years there has been a great deal of progress in the use of variational methods to find periodic, homoclinic and heteroclinic solutions...
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Numerical Analysis of Steady Gradually Varied Flow in Open Channel Networks with Hydraulic Structures
PublikacjaIn this paper, a method for numerical analysis of steady gradually varied fl ow in channel networks with hydraulic structures is considered. For this purpose, a boundary problem for the system of ordinary differential equations consisting of energy equation and mass conservation equations is formulated. The boundary problem is solved using fi nite difference technique which leads to the system of non-linear algebraic equations....
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Kształtowanie toru zwrotnego rozjazdu z odcinkami krzywizny liniowej
PublikacjaW pracy została przedstawiona analityczna metoda kształtowania toru zwrotnego rozjazdu kolejowego posiadającego na swojej długości odcinki krzywizny liniowej. Odróżnia go to w istotny sposób od rozwiązania typowego, stanowiącego pojedynczy łuk kołowy bez krzywych przejściowych. W metodzie tej dokonano identyfikacji problemu rozkładu krzywizny za pomocą równań różniczkowych. Uzyskane rozwiązania mają charakter uniwersalny; m. in....
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Metody zwiększania dostępności i efektywności informatycznej infrastruktury w inteligentnym mieście
PublikacjaW pracy omówiono metody zwiększania dostępności i efektywności informatycznej infrastruktury w inteligentnym mieście. Sformułowano dwa kryteria do oceny rozmieszczenia kluczowych zasobów w systemie smart city. Zobrazowano proces wyznaczania rozwiązań kompromisowych spośród rozwiązań Pareto-optymalnych. Omówiono metaheurystyki inteligencji zbiorowej, w tym roju cząstek, kolonii mrówek, roju pszczół oraz ewolucji różnicowej, za pomocą...
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Verification of algorithms determining wave loads on support structure of wind turbine
PublikacjaThe offshore wind turbines require determination of wave loads on their support structure. This structure is fixed and, therefore, this problem is reduced to solving only the diffraction problem, which is determined by Laplace equation and conditions on the following boundaries: on the support structure, on the sea free surface and on its bottom, and at infinity on free surface. The linear problem was applied to determine the wave...
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Electromagnetic Control and Dynamics of Generalized Burgers’ Nanoliquid Flow Containing Motile Microorganisms with Cattaneo–Christov Relations: Galerkin Finite Element Mechanism
PublikacjaIn our research work, we have developed a model describing the characteristics of the bio-convection and moving microorganisms in the flows of a magnetized generalized Burgers’ nanoliquid with Fourier’s and Fick’s laws in a stretchable sheet. Considerations have been made to Cattaneo–Christov mass and heat diffusion theory. According to the Cattaneo–Christov relation, the Buongiorno phenomenon for the motion of a nanoliquid in...