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1
Content available The DIA-method for navigational integrity
EN
In this contribution we present a review of the DIA-method to ensure navigational integrity. The DIA-method rigorously combines parameter estimation and statistical testing for the Detection, Identification and Adaptation of multivariate and multiple model misspecifications. We describe the statistical properties of the so-obtained DIA-estimator together with its probability density function. Numerical examples are given to highlight various aspects of the navigational DIA-estimator.
2
Content available remote Modelling in the identification of threats to the functioning of technical system
EN
Modern technical systems used in practice (machines, vehicles, military technology) are subject to automatic degradation of the technical condition, which forces modelling to identify changes in this state. The available modelling methods in identifying changes in the technical condition of such systems make it possible to supervise the developing threats to the correctness of their functioning. The aim of the work was to present available methods and tools for modeling and identifying evolving threats to complex technical systems in terms of description and indication of the premises for their use. Modern technical systems (machines and military technology) are characterized by such features as: functionality, reliability, readiness, security, mobility, and operational vulnerability. Identification of threats to the functioning of technical systems through modeling therefore concerns the construction of models of the test object, the reconstruction of the state of the object and its prediction. The existing methods of identification can be divided into methods of identifying static and dynamic properties. The current availability of computers and simulation studies of the dynamics of objects allows attempts to identify the dynamic properties of objects throughout its life cycle, using various models. The considerations presented in this paper concern a modern approach to modeling the dynamic state of objects. The evolutionary dynamic models created in this way should improve the methodology and reasoning in the assessment of the dynamic state, often used for optimization and supporting operational decisions, which is the research niche of this article.
PL
Nowoczesne systemy techniczne stosowane w praktyce (maszyny, pojazdy, technika wojskowa) podlegają automatycznie degradacji stanu technicznego, co wymusza potrzebę modelowania oraz identyfikację zmian tego stanu. Dostępne metody modelowania identyfikacji zmian stanu technicznego takich systemów pozwalają na nadzorowanie powstających zagrożeń dla prawidłowości ich funkcjonowania. Celem pracy było przedstawienie dostępnych metod i narzędzi do modelowania i identyfikacji ewoluujących zagrożeń dla złożonych systemów technicznych w zakresie opisu i wskazań przesłanek do ich wykorzystania. Współczesne systemy techniczne (maszyny i technika wojskowa) charakteryzują się takimi cechami jak: funkcjonalność, niezawodność, gotowość, bezpieczeństwo, mobilność, podatność operacyjna. Identyfikacja zagrożeń dla funkcjonowania systemów technicznych poprzez modelowanie dotyczy więc budowy modeli badanego obiektu, rekonstrukcji stanu obiektu i jego predykcji. Istniejące metody identyfikacji można podzielić na metody identyfikacji właściwości statycznych i dynamicznych. Obecna dostępność komputerów i badań symulacyjnych dynamiki obiektów pozwala na podejmowanie prób identyfikacji właściwości dynamicznych obiektów w całym cyklu ich życia, przy użyciu różnych modeli. Przedstawione w artykule rozważania dotyczą nowoczesnego podejścia do modelowania stanu dynamicznego obiektów. Stworzone w ten sposób dynamiczne modele ewolucyjne powinny usprawnić metodologię i rozumowanie w ocenie stanu dynamicznego, często wykorzystywanych do optymalizacji i wspomagania decyzji operacyjnych, co stanowi niszę badawczą.
EN
The paper proposes a new dynamic model based on the LuGre model and an electrical equation to describe the hysteresis phenomenon for a magnetorheological (MR) damper. In addition, a sliding mode observer (SMO) is proposed to estimate unmeasurable states of the MR damper. The parameters of the MR damper are successfully identified by using the self-learning particle swarm optimization (SLPSO) algorithm. The contributions of this paper are: i) a new dynamic model based on the LuGre model and an electrical equation for an MR damper is successfully formulated to fit for the hysteresis behavior, ii) the exerted damping force can be practically adjusted by using input voltage for the dynamic model, iii) the SMO is proposed to estimate the internal states and current, and iv) the unknown parameters of the MR damper are successfully identified by using the SLPSO algorithm with a numerical experiment.
EN
The operating modes of the automatic control system for electromechanical converters for synchronization of rotor speeds have been developed and investigated. The proposed automatic speed control system allows adjusting the slave engine to the master one in a wide range from 0 to 6000 rpm. To improve the synchronization accuracy an adaptive algorithm is proposed that allows to increase the synchronization accuracy by 3-4 times. The proposed model of an adaptive automatic control system with an observing identification tool makes it possible to minimize the error in the asynchrony of the rotation of the rotors of two electromechanical converters.
EN
Based on the inverse approach and the finite element method, the quality of a reconstructed signal is discussed in this work. The responses caused by a distributed impact on a portion of a composite structure can be recovered using dynamic analysis. The structure is thought to be complex and made up of two different-sized plates made of two different materials. The robustness of the inversion method was studied, as well as the sensitivity of the numerical method compared to modal truncation and sampling of the frequency response function (FRF). Once the FRF had been identified, regularized deconvolution as per generalized singular value decomposition was used to reconstruct the impact signal characteristics. It was revealed that only one mode is required to reconstruct the impact signal.
EN
A refined, fully analytical rheological modelling of thermosetting polymers and unidirectional monotropic fibre-reinforced thermoset matrix (UFRT) composites is presented. New polymers and composites under normal conditions, fully relaxed from curing and post-curing stresses, are modelled. The theory includes quasi-static short-term/medium-term/long-term reversible rheological processes. Thermosets are isotropic materials exhibiting linearly viscoelastic shear strains and linearly elastic bulk strains. Fibres are monotropic (transversely isotropic) and linearly elastic materials. A generic function well reproducing the viscoelastic characteristics of thermosets and UFRT composites is a Mittag-Leffler fractional exponential function in an integral form. Coupled/uncoupled standard/inverse constitutive equations of linear rheology are formulated for thermosets and UFRT composites. The equations are mutually analytically transformable. New rheological models (coded H-R/H) for thermosets and UFRT composites are described by the smallest possible number of material constants. The thermoset is described by two independent elastic constants and three independent viscoelastic constants. The homogenized UFRT composite is described by five independent elastic constants and four independent viscoelastic constants, whereby two visco-elastic constants are common to the matrix and the composite. An improved homogenization theory of UFRT composites, based on analytical solutions of the selected tasks of the theory of linear elasticity, is formulated for monotropic fibres and positively validated experimentally. The viscoelastic constants of the thermoset are calculated analytically in an iterative loop using a long-term unidirectional tension creep experimental test. The viscoelastic constants of the UFRT composite are calculated analytically employing H-R/H shear/quasi-shear storage compliances and VECP (the viscoelastic-elastic correspondence principle) shear/quasi-shear storage compliances. The H-R/H rheological model was validated numerically for selected UFRT composites. The validation tests were performed on the enhanced reliability UFRT composites reported by Soden, Hinton, and Kaddour (Composites Science and Technology, 1998, 2002).
EN
The article deals with estimation of the amount of regolith to be mined with respect to the preparation of lunar habitat. Estimation of the size of the pit is related to the overlay of regolith for habitat made of a composite concrete-like structure. The evaluation is based on the number of inhabitants, necessary floor area, and the considered structure that is made of three segments. The first segment is a linear vault with a half cylinder cross section ending with a half sphere on both sides of the vault. Elementary formulas for the computation of volume of cylinder and sphere are applied.
EN
The main aims of the current research were: (1) to analyze in detail the tensile modulus and ultimate tensile strength (UTS) of orbital wall bones separately for the left and right orbit of the same cadaver and (2) to compare the obtained results with a flexural modulus of the left and right orbit reported earlier by A. C. van Leeuwen et al. [14]. A set of 54 specimens of orbital superior and/or medial walls harvested from 16 human skulls (4 female, 12 male) were tensioned at 0.01 mm/s till fracture. The samples were taken always from both orbits of the same cadaver. For each sample, cross-section area, apparent density, tensile modulus, and UTS were identified. For pooled female and male group apparent density for right and left orbit was identified to be 1.59 (± 0,52 SD) g/cm3 and 1.51 (± 0.48 SD) g/cm3 , tensile modulus 2028 (± 1729 SD) MPa and 2706 (± 2812 SD) MPa, and UTS 14.17 (± 15.00 SD) MPa and 15.03 (± 11.44 SD) MPa, respectively. For tensile tests, there were no statistical differences between the left and right orbit for pooled male and female groups for (a) apparent density (T-Student test p=0.567), (b) UTS (Mann-Whitney U-test p=0.350) and (c) tensile modulus (Mann-Whitney U-test p=0.716). For bending tests, there were no statistical differences between the left and right orbit for the pooled male and female group for (a) orbital wall thickness (T-Student test p=0.811) and (b) flexural modulus (Mann-Whitney Utest p=0.206). The comparative analysis between tensile and flexural moduli for pooled left and right groups (with no distinction for male and female) revealed no statistically significant difference (Mann-Whitney U-test p=0.074). The maximum tensile modulus was 7279 MPa and 9913 MPa for the right and left orbit, respectively, and was similar to the maximum flexural modulus of 6870 MPa and 9170 MPa reported in an earlier study, for the right and left orbit, respectively.
EN
One of the most perspective directions of aircraft engine development is related to implementing adaptive automatic electronic control systems (ACS). The significant elements of these systems are algorithms of matching of mathematical models to actual performances of the engine. These adaptive models are used directly in control algorithms and are a combination of static and dynamic sub-models. This work considers the dynamic sub-models formation using the Least Square method (LSM) on a base of the engine parameters that are measured in-flight. While implementing this function in the (ACS), the problem of checking the sufficiency of the used information for ensuring the required precision of the model arises. We must do this checking a priori (to determine a set of operation modes, the shape of the engine test impact and volume of recorded information) and a posteriori. Equations of the engine models are considered. Relations are derived that determine the precision of parameters of these models’ estimation depending on the precision of measurement, the composition of the engine power ratings, and durability of observations, at a stepwise change of fuel flow. We present these relations in non-dimensional coordinates that make them universal and ready for application to any turboshaft engine.
EN
The paper contains selected research results in the field of identification and metaidentification of the Day Ahead Market system of TGE S.A. Due to the proposed new approach to identification, a methodology for conducting research has been developed, which requires eight stages. Then, both the tasks and research objectives as well as the form of research occurring at all stages of research in order to meet the distinguished specific objectives and the general purpose of the research were shown in detail. Then an example of both identification and metaidentification of Day Ahead Market systems was shown. The obtained models and metamodels confirm the need and possibility of conducting this type of research at TGE S.A.
EN
Aim: As part of this article, an attempt was made to present the legislative process in Poland regarding critical infrastructure, for which valid is the Act of 26 April 2007 on crisis management, specifying, inter alia, authorities competent in crisis management and their tasks and principles of operation in this area as well as implementing acts issued on its basis. The introduced legal regulations define both the concept of critical infrastructure, its protection and activities related to the prevention of crisis situations, reacting in the event of their occurrence and preparation to take control over them, as well as removing their effects and recreating key resources. Introduction: Regulations concerning the protection of critical infrastructure are included in legal acts covering various areas of the country’s functioning, including telecommunications activities, production and trade in fuels and electricity, performance of defence tasks by entrepreneurs, creation of strategic reserves, powers of the minister competent for the State Treasury in some companies, protection of persons and the property. The protection of critical infrastructure is related to the raison d’état, which indicates the need to make special efforts to protect the country’s key infrastructure. Therefore, it is reasonable to present selected legal elements needed to protect critical infrastructure, especially those issues that ensure the continuity of the operation of public administration bodies, which are to ensure the safety of the citizens. Methodology: The article was prepared based on the analysis of the literature on the subject and the analysis of legal acts in the area of strengthening the concept of critical infrastructure, taking into account the current situation related to the pandemic and, consequently, the loss of some officers and employees. During the analysis of the conducted research, compact publications, acts of Polish law as well as guidelines and recommendations published on the websites of governmental institutions were used. Conclusions: In the protection of critical infrastructure, there is a need to introduce legal regulations within the framework of cooperation between institutions. The preparation of effective activities in the area of critical infrastructure requires a comprehensive approach, including: physical, technical, personal, ICT, legal protection, as well as assistance from the government in the reconstruction of the damaged element. Each of the areas mentioned above is a complex set of activities requiring general and specialist knowledge, sometimes expert knowledge, extensive practical experience (using the so-called good practices), risk analysis skills, and risk prediction (profiling).
PL
Cel: W ramach niniejszego artykułu podjęto próbę przybliżenia procesu legislacyjnego w Polsce dotyczącego infrastruktury krytycznej, dla której właściwa jest Ustawa z dnia 26 kwietnia 2007 roku o zarządzaniu kryzysowym określająca m.in. organy właściwe w sprawach zarządzania kryzysowego oraz ich zadania i zasady działania w tym obszarze oraz akty wykonawcze wydane na jej podstawie. Wprowadzone regulacje prawne określają zarówno pojęcie infrastruktury krytycznej, jej ochrony, jak i działań związanych z zapobieganiem sytuacjom kryzysowym, reagowaniem w przypadku ich wystąpienia i przygotowaniem do przejmowania nad nimi kontroli, a także usuwaniu ich skutków oraz odtwarzaniu kluczowych zasobów. Wprowadzenie: Regulacje dotyczące ochrony infrastruktury krytycznej znajdują się w aktach prawnych obejmujących różne dziedziny funkcjonowania państwa, m.in. działalność telekomunikacyjną, wytwarzanie i obrót paliwami oraz energią elektryczną, wykonywanie zadań obronnych przez przedsiębiorców, tworzenie rezerw strategicznych, uprawnienia ministra właściwego do spraw Skarbu Państwa w niektórych spółkach, realizację ochrony osób i mienia. Ochrona infrastruktury krytycznej w swoim przedmiocie związana jest z racją stanu, co wskazuje na konieczność podjęcia szczególnych starań w zakresie ochrony kluczowej infrastruktury państwa. W związku z powyższym zasadne jest przedstawienie wybranych elementów prawnych potrzebnych do ochrony infrastruktury krytycznej, zwłaszcza tych kwestii, które zapewniają ciągłość działania organów administracji publicznej, mających zapewnić bezpieczeństwo obywateli. Metodologia: Artykuł został opracowany przy wykorzystaniu analizy literatury przedmiotu oraz analizy aktów prawnych w zakresie wzmocnienia pojęcia infrastruktury krytycznej, biorąc pod uwagę obecną sytuację związaną z pandemią i co za tym idzie – utratę części funkcjonariuszy i pracowników. Podczas analizy przeprowadzonych badań wykorzystano publikacje zwarte, akty prawa polskiego oraz wytyczne i zalecenia ogłoszone na stronach instytucji rządowych. Wnioski: W ochronie infrastruktury krytycznej zachodzi potrzeba wprowadzenia regulacji prawnych w ramach współpracy między instytucjami. Przygotowanie efektywnych działań w zakresie infrastruktury krytycznej wymaga kompleksowego podejścia, obejmującego ochronę: fizyczną, techniczną, osobową, teleinformatyczną, prawną, a także pomoc strony rządowej w odbudowie zniszczonego (uszkodzonego) elementu. Każdy z wymienionych obszarów stanowi złożony kompleks działań wymagający wiedzy ogólnej oraz specjalistycznej, niekiedy eksperckiej, bogatego doświadczenia praktycznego (korzystania z tzw. dobrych praktyk), umiejętności analizy ryzyka, a także przewidywania (profilowania) zagrożeń.
PL
W artykule przedstawiono metodykę oraz wyniki badań nad wpływem częstotliwości próbkowania na skuteczność systemu NILM. Przeanalizowano zbiór własny zarejestrowany z częstotliwością próbkowania 250 kHz, zawierający zmiany stanu dla 14 urządzeń. Wyznaczono częstotliwość próbkowania powyżej, której nie odnotowuje się poprawy rezultatów identyfikacji dla poszczególnych grup urządzeń.
EN
This paper presents the methodology and results of a research study on the effect of sampling frequency on NILM system performance. Own dataset recorded at a sampling rate of 250 kHz, containing state changes for 14 appliances, was analyzed. A sampling rate above which there is no improvement in identification accuracy for particular appliance groups was determined.
EN
This article provides a simulation and laboratory study of a control system for a two-wheeled differential-drive mobile robot with ROS system. The authors propose an approach to designing a control system based on a parametric model of the robot’s dynamics. The values of unknown parameters of the dynamic model have been determined by means of a Levenberg-Marguardt identification method. By comparing the desired trajectories with those obtained from simulation and laboratory tests, and based on errors analysis, the correctness of the model parameter identification process and the control system operation was then determined.
PL
W artykule przedstawiono badania symulacyjne i laboratoryjne systemu sterowania dwukołowym robotem mobilnym o napędzie różnicowym, z systemem ROS. Autorzy zaproponowali podejście projektowania systemu sterowania w oparciu o parametryczny model dynamiki robota. Wartości nieznanych parametrów modelu dynamiki wyznaczono przeprowadzając ich identyfikację metodą Levenberga-Marguardta. Następnie porównując trajektorie zadane z otrzymanymi na drodze badań symulacyjnych i laboratoryjnych, a także na podstawie analizy uchybów określono poprawność procesu identyfikacji parametrów modelu i działania systemu sterowania.
EN
The paper presents selected research results concerning the identification and simulation of the TGE S.A. Day-Ahead Market (DAM) system of the day for electricity delivered and sold, listed for the following hours: 5:01-6:00, 11:01-12:00, 17:01-18:00 and 23:01-24:00 in 2019, which were obtained in the MATLAB and Simulink environment using the System Identification Toolbox. As a result of identification, four respective discrete parametric arx models were obtained, which were then subject to quality assessment. Then, a simulation model was built in the Simulink environment, which was used for simulation tests and for assessing the sensitivity of the model created using the data from 2019 as the basis and the data from 2020 for verification. The obtained results confirm the correctness of both the performed discrete parametric identification and the possibility of testing the quality of the model and its sensitivity with the use of the DAM system model in the MATLAB and Simulink environment.
EN
The article presents the process of identifying discrete-continuous models with the use of heuristic algorithms. A stepped cantilever beam was used as an example of a discrete-continuous model. The theoretical model was developed based on the formalism of Lagrange multipliers and the Timoshenko theory. Based on experimental research, the theoretical model was validated and the optimization problem was formulated. Optimizations were made for two algorithms: genetic (GA) and particle swarm (PSO). The minimization of the relative error of the obtained experimental and numerical results was used as the objective function. The performed process of identifying the theoretical model can be used to determine the eigenfrequencies of models without the need to conduct experimental tests. The presented methodology regarding the parameter identification of the beams with the variable cross-sectional area (according to the Timosheno theory) with additional discrete components allows us to solve similar problems without the need to exit complex patterns.
EN
It is shown that modern geometry cars, flaw detector cars and other track test cars provide reliable control of the technical condition of all hauls of the railroad track at “certain intervals of time”. Their number is limited and therefore “continuous monitoring” of all hauls is almost impossible. At the same time, in real life, due to the impact of various factors, such as seismic processes, certain changes take place even a day after control. The authors consider one option for continuous monitoring of the beginning of changes in the technical condition of the track using intelligent tools, which allow one, by analyzing the useful signal and the noise from the soil vibrations caused by the rolling stock, to create informative attributes for identifying the technical condition of the track. The application of traditional technologies of correlation and spectral analysis and other methods for this purpose does not allow ensuring adequacy of the control results. This paper proposes a technology for extracting and analyzing useful vibration signals, the noise of vibration signals and the relationship between them. The estimates of both correlation and spectral characteristics of the useful signal and the noise are used as the main carriers of diagnostic information. Due to the simplicity and the reliability of implementation of the proposed technical tools, they can be easily installed in one of the cars of all rolling stocks, providing control of the beginning of changes in the technical condition of the track during their movement in all hauls
EN
The safety and resilience indicators are proposed as crucial tools for analysis, identification, prediction and optimization of COVID-19 pandemic human safety and for minimization and mitigation of pandemic consequences.
EN
There are presented the methods of identification of the climate-weather change process. These are the methods and procedures for estimating the unknown basic parameters of the climate-weather change process semi-Markov model and identifying the distributions of the climate-weather change process conditional sojourn times at the climate-weather states. There are given the formulae estimating the probabilities of the climate-weather change process staying at the particular climate-weather states at the initial moment, the probabilities of the climate-weather change transitions between the climate-weather states and the parameters of the distributions suitable and typical for the description of the climate-weather change process conditional sojourn times at the particular climate-weather states. The proposed statistical methods applications for the unknown parameters identification of the climate-weather change process model determining the climate-weather change process parameters for the port oil piping transportation system and maritime ferry operating areas are presented.
EN
The features of taking into account the change in the properties of the main structural units of induction motors with a high mean-timebetween-failure when identifying their electromagnetic parameters are considered. It enabled the practical research and substantiation of the method of using the obtained results in systems of the industrial variable-frequency electric drive. The efficiency of the proposed solutions for improving energy parameters and ensuring the necessary quality indicators for the regulation of electric drives of pumping and ventilating equipment provided with technological feedback is confirmed.
PL
Uwzględniono cechy zmienności głównych zespołów konstrukcyjnych silników indukcyjnych o wysokim średnim czasie międzyawaryjnym przy identyfikacji ich parametrów elektromagnetycznych. Umożliwiło to praktyczne badania i uzasadnienie metody wykorzystania uzyskanych wyników w układach przemysłowego napędu elektrycznego o zmiennej częstotliwości. Potwierdzono skuteczność proponowanych rozwiązań w zakresie poprawy parametrów energetycznych oraz zapewnienia niezbędnych wskaźników jakościowych do regulacji napędów elektrycznych urządzeń pompowo-wentylacyjnych wyposażonych w sprzężenie zwrotne technologiczne.
EN
Digitization and automation are transforming traditional systems for monitoring and managing objects in exteriors. Innovative farms are gradually moving in livestock management systems from paper reporting to integrated, shared and autonomous services throughout the livestock live-cycle. Although autonomous monitoring is a reality today, the benefits of autonomous monitoring by unmanned aerial systems (UAVs) for animal identification and authentication do not lie in the herd itself, but in what aerial systems can offer when operated and managed in an integrated ecosystem. At present, UAVs are little used in the agro sector as a concept “mobility-as-a-service” (MaaS), because farmers themselves in the real environment are not able to respond flexibly to technological innovations and adapt to the demand for monitoring and providing authentic data in real-time to the subsidy payment system. The focus of the paper is the presentation of a procedure targeted on design of an objects monitoring system in exterior according to defined parameters with selected main and specific data; taking in the account predefined parameters at the same time, the requirements for technological means and software with the support of machine learning for livestock identification as well as composition of selected technical equipment using the IoT concept with unique beacons for subsequent data processing in the reliable authentication methodology of every monitored objects are defined.
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