Wyniki wyszukiwania - BazTech

1

An installation angle error calibration method in an Ultra-Short Baseline system based on a dual transponder

Liu Baoheng, Zhang Xiaochuan, Jia Shuyang, Zou Sichen, Tian Deyan, Da Lianglong

Polish Maritime Research

|

2023

|

nr 2

121--129

EN

The installation error of an acoustic transceiver array is one of the important error sources in an ultra-short baseline (USBL) system. In a USBL system with a positioning accuracy of 0.5%, an installation error angle of 1 will lead to a positioning error of 1.7% times the slant distance. In this paper, a dual transponder-based installation angle error calibration method for USBL is proposed. First, the positioning errors induced by various installation angles are deduced and analysed using the linear measurement of seafloor targets. Then, an iterative algorithm is proposed that estimates the rolling alignment error, pitching alignment error, and heading alignment error, in that order. The simulation and experienced results show that, after three iterations, the estimates of the three alignment errors can converge quickly, all of the estimates converge to within 0.001 and the estimated values are very close to the true values. The horizontal positioning error caused by the installation error angle can be reduced by nearly 75%. The method has good effectiveness and robustness, and can greatly improve the positioning accuracy of the USBL system.

2

Analysis of pandemic with game methodology and numerical approximation

Matusik Radosław, Nowakowski Andrzej

Archives of Control Sciences

|

2023

|

Vol. 33, No. 3

651--680

EN

We build a mathematical game model of pandemic transmission, including vaccinations of population and budget costs of different acting to eliminate pandemic. We assume the interactions among different groups: vaccinated, susceptible, exposed, infectious, super-spreaders, hospitalized and fatality, defining a system of ordinary differential equations, which describes compartment model of disease and costs of the treatment. The goal of the game is to describe the development disease under different types of treatment, but including costs of them and social restrictions, during the shortest time period. To this effect we construct a dual dynamic programming method to describe open-loop Nash equilibrium for treatment, a group of people having antibodies and budget costs. Next, we calculate numerically an approximate open-loop Nash equilibrium.

3

Algorytm inspirowany polem walki - połączenie algorytmów numerycznych z ideą roju

Baumgart Jan, Sangho Belco

Studia i Materiały Informatyki Stosowanej

|

2021

|

nr 2

26--31

PL

Artykuł przedstawia przygotowany algorytm na bazie połączenia idei znanych metod numerycznych z metodami opartymi na idei roju. Algorytm został przygotowany z inspiracji polem walki podczas którego w równych odstępach żołnierze przeczesują siły wroga z różnymi prędkościami zależnie od posiadanego orężu a następnie ograniczają zakres pola bitwy. Zaproponowane rozwiązanie wywodzi się właśnie ze zbliżonych założeń. Głównym założeniem pracy było przedstawienie potencjalnego zysku z połączenia metod optymalizacji oraz porównanie metody mieszanej z metodami bazującymi na idei roju pod względem prędkości działania oraz skuteczności odnajdowania optimum globalnego.Algorytm został porównany z dwoma algorytmami metaheurystycznymi pod kątem dokładności odnalezionych rozwiązań oraz prędkości. Zgodnie z wynikami eksperymentów posiada wydajność podobną w porównaniu z innymi algorytmami oraz daje zadowalające efekty w wykorzystaniu.

EN

he article presents prepared algorithm based on the combination of the ideas of known numericalmethods with methods based on the idea of a swarm. The algorithm was prepared inspired by the battlefield,during which, at equal intervals, soldiers scour enemy forces at different speeds depending on the weapon theyhave, and then limit the scope of the battlefield. The proposed solution is based on similar assumptions. Themain assumption of the work was to present the potential profit from the combination of optimization methodsand to compare the mixed method with methods based on the idea of a swarm in terms of operating speed andthe effectiveness of finding the global optimum. The algorithm was compared with two metaheuristic algorithmsin terms of the accuracy of the solutions found and speed. According to the results of the experiments, it hasa similar performance compared to other algorithms and gives satisfactory results in use.

4

Differential quadrature methodfor some diffusion-reaction problems

Szukiewicz Mirosław K.

Chemical and Process Engineering

|

2020

|

Vol. 41, nr 1

3--11

EN

In the paper, differential quadrature method (DQM) is used to find numerical solutions of reaction-diffusion equations with different boundary conditions. The DQM-method changes the reaction-diffusion equation (ordinary differential equation) into a system of algebraic equations. The obtainedsystem is solved using built-in procedures of Maple®(Computer Algebra System-type program).Calculations were performed with Maple®program. The test problems include reaction-diffusionequation applied in heterogeneous catalysis. The method can be employed even in relatively hard tasks(e.g. ill-conditioned, free boundary problems).

5

Deep learning of the role of interleukin IL-17 and its action in promoting cancer

Nutini Alessandro, Sohail Ayesha

Bio-Algorithms and Med-Systems

|

2020

|

Vol. 16, no. 4

art. no. 20200052

EN

In breast cancer patients, metastasis remains a major cause of death. The metastasis formation process is given by an interaction between the cancer cells and the microenvironment that surrounds them. In this article, we develop a mathematical model that analyzes the role of interleukin IL-17 and its action in promoting cancer and in facilitating tissue metastasis in breast cancer, using a dynamic analysis based on a stochastic process that accounts for the local and global action of this molecule. The model uses the Ornstein-Uhlembeck and Markov process in continuous time. It focuses on the oncological expansion and the interaction between the interleukin IL-17 and cell populations This analysis tends to clarify the processes underlying the metastasis expansion mechanism both for a better understanding of the pathological event and for a possible better control of therapeutic strategies. IL-17 is a proinflammatory interleukin that acts when there is tissue damage or when there is a pathological situation caused by an external pathogen or by a pathological condition such as cancer. This research is focused on the role of interleukin IL-17 which, especially in the case of breast cancer, turns out to be a dominant “communication pin” since it interconnects with the activity of different cell populations affected by the oncological phenomenon. Stochastic modeling strategies, specially the Ornstein-Uhlenbeck process, with the aid of numerical algorithms are elaborated in this review. The role of IL-17 is discussed in this manuscript at all the stages of cancer. It is discussed that IL-17 also acts as “metastasis promoter” as a result of its proinflammatory nature. The stochastic nature of IL-17 is discussed based on the evidence provided by recent literature. The resulting dynamical analysis can help to select the most appropriate therapeutic strategy. Cancer cells, in the case of breast cancer, have high level of IL-17 receptors (IL-17R); therefore the interleukin itself has direct effects on these cells. Immunotherapy research, focused on this cytokine and interlinked with the stochastic modeling, seems to be a promising avenue.

6

Numerical Algorithm for the Solutions of Fractional Order Systems of Dirichlet Function Types with Comparative Analysis

Arqub Omar Abu

Fundamenta Informaticae

|

2019

|

Vol. 166, nr 2

111--137

EN

The aim of this article is to introduce the reproducing kernel algorithm for obtaining the numerical solutions of fractional order systems of Dirichlet function types. The algorithm provide appropriate representation of the solutions in infinite series formula with accurately computable structures. By interrupting the n-term of exact solutions, numerical solutions of linear and nonlinear time-fractional equations of homogeneous and nonhomogeneous function type are studied from mathematical viewpoint. Convergence analysis, error estimations, and error bounds for the present algorithm are also discussed. The dynamical properties of these numerical solutions are discussed and the profiles of several representative numerical solutions are illustrated. Finally, the utilized results show that the present algorithm and simulated annealing provide a good scheduling methodology to such systems compared with other numerical methods.

7

Application of Residual Power Series Method for the Solution of Time-fractional Schrödinger Equations in One-dimensional Space

Arqub Omar Abu

Fundamenta Informaticae

|

2019

|

Vol. 166, nr 2

87--110

EN

The object of this article is to present the computational solution of the time-fractional Schrödinger equation subject to given constraint condition based on the generalized Taylor series formula in the Caputo sense. The algorithm methodology is based on construct a multiple fractional power series solution in the form of a rabidly convergent series with minimum size of calculations using symbolic computation software. The proposed technique is fully compatible with the complexity of this problem and obtained results are highly encouraging. Efficacious computational experiments are provided to guarantee the procedure and to illustrate the theoretical statements of the present algorithm in order to show its potentiality, generality, and superiority for solving such fractional equation. Graphical results and numerical comparisons are presented and discussed quantitatively to illustrate the solution.

8

Analytical and numerical solving of right triangles with given a difference of two sides length and the acute angle

Czajkowski Andrzej Antoni, Oleszak Wojciech Kazimierz, Snastin Sławomir Wawrzyniec, Rewkowski Lech Adam

Problemy Nauk Stosowanych

|

2018

|

T. 9

5--20

EN

Introduction and aims: The paper shows the analytical models of solving right triangles with appropriate discussion. For right triangles have been discussed six cases taking into account the acute angle and the difference of two sides length in the right triangle. The main aim of this paper is not only to create some analytical algorithms for solving right triangle, but also their implementation in programs MS-Excel, MathCAD and Mathematica. Material and methods: Elaboration of six analytical cases of solving right triangles has been made on the basis of the relevant trigonometric properties occurring in a right triangle. In the paper have been used some analytical and numerical methods by using MS-Excel, MathCAD and Mathematica programs. Results: As some results have been obtained numerical algorithms in the programs MS-Excel, MathCAD and Mathematica for six analytical cases of solving right triangles taking into account the acute angle and the difference of two side length in the right triangle. Conclusion: Created numerical algorithms of solving the right triangles in the programs MS-Excel, MathCAD and Mathematica allow for faster significant performance calculations than the traditional way of using logarithms and logarithmic tables.

PL

Wstęp i cele: W pracy pokazano analityczne modele rozwiązywania trójkątów prostokątnych wraz z odpowiednią dyskusją. Dla trójkątów prostokątnych omówiono sześć przypadków z uwzględnieniem kąta ostrego oraz różnicy długości dwóch boków trójkąta. Głównym celem jest pracy jest nie tylko utworzenie algorytmów analitycznych rozwiązywania takich trójkątów lecz również ich implementacja w programach MS-Excel, MathCAD i Mathematica. Materiał i metody: Opracowanie sześciu analitycznych przypadków rozwiązywania trójkątów prostokątnych wykonano opierając się odpowiednich własnościach trygonometrycznych występujących w trójkącie prostokątnym. Zastosowano metodę analityczną i numeryczną wykorzystując programy MS-Excel, MathCAD i Mathematica. Wyniki: Otrzymano algorytmy numeryczne w programach MS-Excel, MathCAD i Mathematica dla sześciu analitycznych przypadków rozwiązywania trójkątów prostokątnych z uwzględnieniem kąta ostrego oraz różnicy długości dwóch boków trójkąta. Wniosek: Utworzone algorytmy numeryczne rozwiązywania trójkątów prostokątnych w programach MS-Excel, MathCAD oraz Mathematica, pozwalają na znaczne szybsze wykonanie obliczeń niż drogą tradycyjną z użyciem logarytmów i tablic logarytmicznych.

9

A Numerical Algorithm and a Variational Iteration Technique for Solving Higher Order Fuzzy Integro-differential Equations

Narayanamoorthy S., Murugan K.

Fundamenta Informaticae

|

2014

|

Vol. 133, nr 4

421--431

EN

In this paper, we present an algorithmic form of the variational iteration method (VIM) to handle both linear and nonlinear higher order fuzzy integro-differential equations. Using parametric form of fuzzy numbers to convert higher order fuzzy integro-differential equation to a system of higher order integro-differential equations in crisp case. By using the variational integration method we find the approximate solution of this system and consequently we obtain an approximation for fuzzy solution of the higher order fuzzy integro-differential equations. The numerical results are examined.

10

A Damageable Spring

Chipman J. C., Roux A., Shillor M., Sofonea M.

Machine Dynamics Research

|

2011

|

Vol. 35, No. 1

82-96

EN

The evolution of material damage in a nonlinear spring is modeled, analyzed, and numerically simulated. The material damage is described by a damage function whose evolution depends on the mechanical energy in the system and the damage threshold. The model is in the form of two coupled nonlinear ordinary differential equations. The existence of the unique solution is proved using arguments for evolutionary equations with maximal monotone operators, differential equations, and fixed points. The scaling properties of the model are discussed. A numerical algorithm for the problem is presented and four simulations of the system behavior depicted. In particular, the changes in the oscillations of the system as damage progresses are shown.

11

Wrażliwość powłoki cylindrycznej na zmianę grubości

Kubiak H., Grzywiński M.

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

|

2010

|

Z. 16 (166)

111-120

PL

W pracy przedstawiono algorytmy analizy wrażliwości układów powłokowych. Oprócz modelowania różniczkowania bezpośredniego, sformułowano sprzężone zagadnienie końcowe bazujące na pierwotnym zagadnieniu początkowym, przydatne w analizie wrażliwości. Opracowano algorytm numeryczny, łatwo implementowany w istniejących pakietach elementów skończonych. Zaprezentowano i przedyskutowano liczbowe wyniki analizy wrażliwości dla powłoki cylindrycznej.

EN

A numerical formulation for sensitivity analysis of shell structure is presented in the paper. In addition to modeling the direct differentation coupled to the find question was formulated based on primary issue of use in the initial sensitivity analysis. An algorithm for numerical easily implemented in existing finite element packages. There were presented and discussed numerical results of sensitivity analysis for shell cylindrical.

12

Metoda elementów skończonych dla początkujących

Witkowski J.

Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Edukacja Techniczna i Informatyczna

|

2009

|

T. 4

9-201

EN

The paper presents approximate methods of solving differentia equations, dealing mostly with practical aspects FEM such as principles of formulating finite elements and super-elements, transforming their mechanical and thermo-mechanical properties. The paper presents also numerical algorithms of FEM including non-linear problems. All examples of application refer to machine design. The finite elements in a set included in the paper relate to the same problems.

13

Numerical model of the ammonia oxidation process on catalyst gauzes

Dziuba K., Petera J.

Zeszyty Naukowe. Inżynieria Chemiczna i Procesowa / Politechnika Łódzka

|

2007

|

Z. 31

21-35

EN

A literature survey has been done on the modelling of the ammonia oxidation process on catalyst gauzes used in technology of nitric production. On the basis of the analysis a new mathematical model of this process including the main reactions kinetics, has been derived and implemented in an original numerical algorithm based on the finite element method. The model is capable of showing of reaction components concentrations. Gas and gauzes temperatures throughout the catalyst bed as well as determination of influence of gauzes number and their configuration on the ammonia oxidation efficiency. The influence of inlet gas mixture conditions on the outlet temperature has been investigated and compared with the measurements obtained from a production plant.

PL

Dokonano krytycznego przeglądu literatury na temat modelowania procesu utleniania amoniaku na siatkach katalitycznych wykorzystywanego w technologii produkcji kwasu azotowego. Na podstawie tej analizy opracowano nowy model matematyczny tego procesu, który zaimplementowano w oryginalnym algorytmie numerycznym opartym na metodzie elementu skończonego. Umożliwia on śledzenie stężeń składników reakcji, temperatury gazów i katalizatora wzdłuż złoża katalicznego oraz pozwala na określenie wpływu liczby siatek katalitycznych na sprawność utleniania amoniaku. Model został zweryfikowany na podstawie danych doświadczalnych otrzymanych z instalacji produkcyjnej kwasu azotowego.

14

Model numeryczny procesu utleniania amoniaku na siatkach katalitycznych

Dziuba K., Petera J.

Zeszyty Naukowe. Inżynieria Chemiczna i Procesowa / Politechnika Łódzka

|

2007

|

Z. 31

5-19

PL

Dokonano krytycznego przeglądu literatury na temat modelowania procesu utleniania amoniaku na siatkach katalitycznych wykorzystywanego w technologii produkcji kwasu azotowego. Na podstawie tej analizy opracowano nowy model matematyczny tego procesu, który zaimplementowano w oryginalnym algorytmie numerycznym opartym na metodzie elementu skończonego. Umożliwia on śledzenie stężeń składników reakcji, temperatury gazów i katalizatora wzdłuż złoża katalicznego oraz pozwala na określenie wpływu liczby siatek katalitycznych na sprawność utleniania amoniaku. Model został zweryfikowany na podstawie danych doświadczalnych otrzymanych z instalacji produkcyjnej kwasu azotowego.

EN

A literature survey has been done on the modelling of the ammonia oxidation process on catalyst gauzes used in technology of nitric production. On the basis of the analysis a new mathematical model of this process including the main reactions kinetics, has been derived and implemented in an original numerical algorithm based on the finite element method. The model is capable of showing of reaction components concentrations. Gas and gauzes temperatures throughout the catalyst bed as well as determination of influence of gauzes number and their configuration on the ammonia oxidation efficiency. The influence of inlet gas mixture conditions on the outlet temperature has been investigated and compared with the measurements obtained from a production plant.

15

The numerical algorithm of solidification modelling using the micro-macro approach

Ciesielski M.

Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej

|

2007

|

Vol. 6, nr 1

41-46

EN

In this paper the numerical algorithm simulating the solidification process on the micro/macro level is presented. In order to solve the problem the control volume method is applied. The casting domain is covered by the mesh of regular macro-cells and next in every macro-cell the mesh of control volumes is generated. The control volumes correspond to the final shape of grains and they are approximated by the Thiessen polygons (2D task), while their central points correspond to the initial positions of nuclei (generated in a random way). The changes of temporary volumetric fraction of solid at the considered point from casting domain result from the laws determining the nucleation and nuclei growth. In the final part of the paper the example of computation is shown.

16

A numerical algorithm for obtaining an optimal temperature distribution in a 3D triple layered cylindrical skin structure

Zhang L., Dai W., Nassar R.

Computer Assisted Mechanics and Engineering Sciences

|

2007

|

Vol. 14, No. 1

107-125

EN

In recent years, there has been interest in research related to hyperthermia combined with radiation and cytotoxic drugs to enhance the killing of tumors. The objective is to control laser heating of the tumor so that the temperature of the normal tissue surrounding the tumor remains low enough so as not to cause damage to the tissue. To achieve this objective, it is important to obtain an optimal temperature field of the entire treatment region. In this paper, we develop a numerical algorithm for obtaining an optimal temperature distribution in a 3D triple layered cylindrical skin structure by pre-specifying the temperatures to be obtained at the center and perimeter of the treated region on the skin surface. The method is comprised of designing a laser irradiation pattern, solving a 3D Pennes' bioheat equation by a numerical scheme, and optimizing the laser power.

17

Wyznaczanie ruchu cieczy lepkiej metodą sztucznej ściśliwości na siatkach nierównomiernych

Kosma Z., Noga B., Motyl P.

Modelowanie Inżynierskie

|

2006

|

T. 1, nr 32

261-266

PL

Przedstawione zostały własne algorytmy numeryczne, przeznaczone do wyznaczania dwu- i trojwymiarowego, stacjonarnego ruchu cieczy lepkiej metodą sztucznej ściśliwości w obszarach zagłębień: kwadratowego i sześciennego z jedną poruszającą się ścianką. Zagadnienia te rozwiązywano metodą prostych, sprowadzając zagadnienia początkowo-brzegowe dla układow rownań rożniczkowych cząstkowych do zagadnień początkowych dla układow równań różniczkowych zwyczajnych. Obliczenia wykonano na nierównomiernych siatkach 30 �x30 oraz 30 �x30 x30 dla Re <_1000.

EN

The artificial compressibility method is designed for computation of stationary viscous incompressible flows in the square and cubic cavities. The spatial derivatives and the boundary conditions are discretized by means of the classical second-order finite-difference schemes on non-uniform grids, while preserving the time-variable continuos. The resulted system of ordinary differential equations has been integrated using the one-step backward-differentiation predictor-corrector method. Calculations have been made for Reynolds number values of 400 and 1000 on the 30 × 30 and 30 × 30 × 30 non-uniform grids.

18

Wyznaczanie ruchu cieczy lepkiej metodą sztucznej ściśliwości na siatkach nakładających się

Kosma Z., Noga B., Motyl P.

Modelowanie Inżynierskie

|

2006

|

T. 1, nr 32

267-272

PL

Przedstawione zostały własne algorytmy numeryczne, przeznaczone do wyznaczania dwuwymiarowego, stacjonarnego ruchu cieczy lepkiej metodą sztucznej ściśliwości w obszarach kanałów prostoliniowych, podwójnie zagiętych. Kanały wlotowe i wylotowe mają stałe długości, różne są długości kanałów pośrednich. Zagadnienia te rozwiązywano metodą prostych, sprowadzając zagadnienia początkowo-brzegowe dla układów równań różniczkowych cząstkowych do zagadnień początkowych dla układów równań różniczkowych zwyczajnych. Obliczenia wykonano na trzech równomiernych, nakładających się siatkach 30Lx30 w kanałach L=2-9 dla Re <_200.

EN

The artificial compressibility method is designed for computation of stationary viscous incompressible flows in double bent channels. The spatial derivatives and the boundary conditions are discretized by means of the classical secondorder finite-difference schemes on three overlapping uniform grids, while preserving the time-variable continuos. The resulted system of ordinary differential equations has been integrated using the two-step backward-differentiation predictorcorrector method. Calculations have been made for Re<_ 200 on three uniform 30 L �x30 grids for the channels lengths L = 2 -9.

19

Applying the Interval Multistep Methods of Adams Type to Solution Simple Pendulum Problem

Jankowska M.

Vibrations in Physical Systems

|

2004

|

Vol. 21

167--170

20

Rozwiązywanie zagadnienia opływu profilu lotniczego cieczą lepką dla funkcji prądu

Kosma Z., Noga B.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

|

2003

|

z. 20

232-237

PL

Przedstawione zostały własne algorytmy numeryczne, przeznaczone do obliczania płaskiego ruchu cieczy lepkiej wokół profilu lotniczego, nachylonego do kierunku napływu pod dużym kątem natarcia - oparte na rozwiązywaniu zagadnienia początkowo-brzegowego dla pełnych równań Naviera-Stokesa, sprowadzonych do równania czwartego rzędu dla funkcji prądu. Obliczenia zostały wykonane na równomiernej siatce 100 x 100 w obszarze kanonicznym dla dwóch liczb Reynoldsa: Re = 200, Re = 400. Jako warunki: początkowe i brzegowe na granicy zewnętrznej przyjęto rozwiązania dla opływu profilu cieczą doskonałą.

EN

The purpose of this paper is to simulate the plane motion of viscous incompressible fluid around an aerofoil at large angle of attack. The developed numerical algorithms are based on solving an initial-boundary value problem for the full incompressible Navier-Stokes equations, written in the form of the fourth-order equation for the stream function. Calculations have been made on the uniform grid 100 x 100 in a canonical domain at Reynolds numbers of Re = 200 and Re = 400. The initial and the outer boundary conditions used for the computation are the solutions of irrotational flow of ideal fluid.