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1

Optimal Method for Polarization Selection of Stationary Objects Against the Background of the Earth’s Surface

Volosyuk Valerii, Zhyla Simeon, Pavlikov Vladimir, Ruzhentsev Nikolay, Tserne Eduard, Popov Anatoliy, Shmatko Oleksandr, Dergachov Kostiantyn, Havrylenko Olena, Ostroumov Ivan, Kuzmenko Nataliia, Sushchenko Olga, Averyanova Yuliya, Zaliskyi Maksym, Solomentsev Oleksandr, Kuznetsov Borys, Nikitina Tatyana

International Journal of Electronics and Telecommunications

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2022

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Vol. 68, No. 1

83--89

EN

Within the maximum likelihood method an optimal algorithm for polarization target selection against the background of interfering signal reflected from the earth’s surface is synthesized. The algorithm contains joint operations of spectral interference rejection and their polarization compensation by means of certain combinations of interchannel subtraction of signals of different polarizations. The physical features of the elements of the polarization scattering matrix are investigated for the technical implementation of the synthesized algorithm.

2

Comparison of conventional and differential evolution based parameter estimation methods on the food frequency analysis

Yilmaz Muhammet, Tosunoglu Fatih, Demirel Mehmet Cüneyd

Acta Geophysica

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2021

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Vol. 69, no. 5

1887--1900

EN

Accurate estimation of food frequency is an important task for water resources management. This starts with appropriate selection of probability distribution to food samples (annual maximum flows) that is of great importance for food frequency analysis (FFA). In order to reach the most precise estimation, the probability distribution of the considered time series should be well defined and its parameters should be more accurately estimated. First time in the FFA literature, a differential evolution-based parameter estimation method is applied to obtain the parameters of probability distribution functions and is compared with the traditional maximum likelihood method (MLM) in the present study. For this purpose, eleven distributions have been used to describe the annual maximum food series of nine gauging sites, with the performance of each distribution being investigated based on six criteria. The results revealed that a single distribution cannot be specified as the best-ft distribution for the study area. Moreover, it has been found that the applied approach improves the probability prediction of foods better than MLM method for efficient design of hydraulic structures, risk analysis and floodplain management.

3

Assessment model of cutting tool condition for real-time supervision system

Kozłowski Edward, Mazurkiewicz Dariusz, Żabiński Tomasz, Prucnal Sławomir, Sęp Jarosław

Eksploatacja i Niezawodność

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2019

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Vol. 21, no. 4

679--685

EN

Further development of manufacturing technology, in particular machining requires the search for new innovative technological solutions. This applies in particular to the advanced processing of measurement data from diagnostic and monitoring systems. The increasing amount of data collected by the embedded measurement systems requires development of effective analytical tools to efficiently transform the data into knowledge and implement autonomous machine tools of the future. This issue is of particular importance to assess the condition of the tool and predict its durability, which are crucial for reliability and quality of the manufacturing process. Therefore, a mathematical model was developed to enable effective, real-time classification of the cutting blade status. The model was verified based on real measurement data from an industrial machine tool.

PL

Dalszy rozwój inżynierii produkcji, w szczególności obróbki skrawaniem, wymaga poszukiwania nowych innowacyjnych rozwiązań technologicznych. Dotyczy to w szczególności zaawansowanego przetwarzania danych pomiarowych pochodzących z systemów diagnostycznych i monitorujących. Rosnąca ilość danych gromadzonych przez wbudowane systemy pomiarowe wymaga opracowania skutecznych narzędzi analitycznych, aby efektywnie przekształcać dane w wiedzę i wdrażać autonomiczne obrabiarki przyszłości. Kwestia ta ma szczególne znaczenie dla oceny stanu narzędzia i przewidywania jego trwałości, które są kluczowe dla niezawodności i jakości procesu produkcyjnego. Dlatego opracowano nowy model matematyczny, którego zadaniem jest skuteczna klasyfikacja stanu ostrza narzędzia skrawającego realizowana w czasie rzeczywistym. Opracowany model został zweryfikowany na podstawie rzeczywistych danych pomiarowych z przemysłowej obrabiarki.

4

GARCH(1,1) models with stable residuals

Trusz M., Tserakh U.

Studia Informatica : systems and information technology

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2018

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Vol. 1-2(22)

47--57

EN

The focus of this paper is the use of stable distributions for GARCH models. Such models are applied for the analysis of financial and economic time series, which have several special properties: volatility clustering, heavy tails and asymmetry of residuals distributions. Below we compare the properties of stable and tempered stable distributions and describe methodologies for constructing models and subsequent estimation of parameters using the maximum likelihood method. We also analyze an example of building models on real data in order to illustrate that tempered stable distributions could be used in financial time series models. Moreover, such distributions can show better results in comparison with traditionally used distributions.

5

Analysis of parameters of rail vehicles

Knopik L.

Journal of Polish CIMAC

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2013

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Vol. 8, no 2

32--40

EN

In this paper, mixture of two normal distributions is proposed to accommodate the values of rail vehicles parameters. We also present the most commonly used maximum likelihood estimation to fit the two component mixture of normal distribution using data sets of rail vehicles.

6

Wykorzystanie filtru cząsteczkowego w problemie identyfikacji układów automatyki

Kozierski P.

Prace Instytutu Elektrotechniki

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2012

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Z. 260

157-169

PL

W artykule przedstawiono sposób identyfikacji parametrycznej obiektów nieliniowych zapisanych w przestrzeni stanu. Identyfikacja wykorzystuje metodę największej wiarygodności (ML), z zastosowaniem filtru cząsteczkowego i algorytmu oczekiwanie-maksymalizacja (EM).

EN

A way of parameter estimation of nonlinear dynamic systems in state-space form is presented. The identification uses Maximum Likelihood method (ML), Particle Filter approach and Expectation-Maximization algorithm (EM).

7

Statistical analysis of failures

Knopik L.

Journal of Polish CIMAC

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2012

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Vol. 7, no 2

91-95

EN

The lifetime distribution is important in reliability studies. There are many situations in lifetime testing, where an item (technical object) fails instantaneously and hence the observed lifetime is reported as a small real positive number. The investigation in this article was motivated by an extended and generalized Weibull distribution. We suggest a mixture of a singular distribution and Weibull distribution. We apply the maximum likelihood method to estimate the parameters of the mixture. The method is illustrated by a numerical example for the time between the failures of bus engines.

8

Niezawodność wybranych par ciernych pierścień tłokowy–tuleja cylindrowa

Kaczor G.

Czasopismo Techniczne. Mechanika

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2012

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R. 109, z. 9-M

101--110

PL

Problematyka niezawodności współczesnych obiektów technicznych nabiera szczególnego znaczenia ze względu na wzrost ich złożoności. Narzędziami zwiększającymi efektywność analiz niezawodności są aplikacje komputerowe umożliwiające m.in. prowadzenie symulacji czasu poprawnej pracy systemów, prognozowanie niezawodności oraz jej optymalizację. W niniejszym artykule zdecydowano się wykorzystać aplikację Weibull++ do modelowania niezawodności skojarzenia pierścień tłokowy–tuleja cylindrowa na podstawie danych empirycznych przedstawionych w pracy [5].

EN

The problems of reliability of modern technical facilities is of particular importance due to the increase in their complexity. The tools that increase the efficiency of reliability analysis are computer applications, including simulation of reliability, prediction and optimization. In this paper, it was decided to use the Weibull++ application to associate reliability modeling piston ring – cylinder sleeve based on life data presented in.

9

Analiza niezawodności wtryskiwaczy

Zając G., Kaczor G.

Czasopismo Techniczne. Mechanika

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2012

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R. 109, z. 7-M

327--334

PL

Wzrost wymagań w zakresie spełniania coraz ostrzejszych norm dotyczących emisji toksycznych substancji oraz zmniejszania zużycia paliwa przez nowoczesne silniki wysokoprężne powoduje, że elementy układów wtryskowych pracują w warunkach zwiększonych obciążeń, temperatur i ciśnień. Ma to istotny wpływ na ich niezawodność i trwałość. W artykule przedstawiono analizę niezawodności wtryskiwaczy metodą największej wiarygodności.

EN

The increase in meeting the requirements of increasingly stringent emission standards for toxic substances and reduce fuel consumption of diesel engines, makes the elements of the injection systems operate under higher loads, temperatures and pressures. It impacts significantly on their reliability and durability. This article contains an analysis of reliability of the injectors based on the maximum likelihood method.

10

Modeling and identification of actuator for flap deflection

Ulinowicz M., Narkiewicz J.

Journal of Automation Mobile Robotics and Intelligent Systems

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2011

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Vol. 5, No. 4

35-40

EN

The electromechanical actuator (EMA) model is presented with the methods for identifying its design parameters. The actuator is a part of the system for flap deployment on the commercial transport airplane. The differential equations with the feedback control describe behaviour of the actuator deflection. There are two concepts of drive system simultaneously considered: a high torque/low speed (HT/LS) and a geared low torque/high speed (LT/HS). For parameter identification in both cases the Maximum Likelihood (ML) method with two minimisation algorithms: linearized Gauss-Newton and Levenberg-Marquardt is applied. Both approaches for each of two design solutions were effective, while tested on hypothetical data.

11

The errors-in-variable model in the optimal portfolio construction

Czapkiewicz A., Machowska M.

Decision Making in Manufacturing and Services

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2007

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Vol. 1, no. 1-2

49-57

EN

In the paper we consider a modification of Sharpe's method used in classical portfolio analysis for optimal portfolio building. The conventional theory assumes there is a linear relationship between asset's return and market portfolio return, while the influence of all the other factors is not included. We propose not to neglect them any more, but include them into a model. Since the factors in question are often hard to measure or even characterize, we treat them as a disturbances on random variables used by classical Sharpe's method. The key idea of the paper is the modification of the classical approach by application of the errors-in-variable model. We assume that both independent (market portfolio return) as well as dependent (given asset's return) variables are randomly distributed values related with each other by linear relationship and we build the model used for parameters' estimation. To verify the model, we performed an analysis based on archival data from Warsaw Stock Exchange. The results are also included.

12

Modelling and identification of the respiratory control system

Noshiro M., Fukuoka Y., Nebuya S.

Biocybernetics and Biomedical Engineering

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2000

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Vol. 20, no. 3

93-108

EN

Computer simulation using the models of the human gas exchange system showed that the PaC0(2) behavior of the Iinearized model agrees weII with those of other models in the range of 90 to 120 percent of normaI alveolar ventiIation. The pulmonary blood flow caIculated from the estimates in the Iinearized model of the CO(2) uptake system was significantIy correlated with the measured flow in the animaI experiment. This result indicates that the Iinearized model is adequate. A new method is proposed to-identify the nonIinear P(co2) controlIing system using a combination of a neural network and a polynomial NARMAX model. Computer simulation showed that the proposed method worked weIl.

PL

Symulacja komputerowa wykorzystująca modele wymiany gazowej pokazuje, że zmienność PaCO(2) w modelu zlinearyzowanym odpowiada zmienności PaCO(2) w innych modelach, w zakresie zmian od 90 do 120% standardowej wentylacji pęcherzykowej. Perfuzja obliczana ze wskaźników w liniowym modelu zużycia CO(2) była dobrze skorelowana z płucnym przepływem krwi mierzonym podczas badań na zwierzętach. Fakty te wskazują na to, że model liniowy jest adekwatny. W pracy zaproponowano nową metodę do identyfikacji nieliniowego układu sterowania PaCO(2) wykorzystując kombinację sieci neuronowej i polynominalnego modelu NARMAX. Symulacja komputerowa wykazała, że zaproponowana metoda daje oczekiwane rezultaty.