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Search results for: FAULT DIAGNOSIS, MAINTENANCE, GAUSSIAN PROCESSES, PROCESS MODELING
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Fault detection and diagnostics of complex dynamic systems using Gaussian Process Models - nuclear power plant case study
PublicationThe article examines the use of Gaussian Process Models to simulate the dynamic processes of a Pressurized Water nuclear Reactor for fault detection and diagnostics. The paper illustrates the potential of Gaussian Process Models as a tool for monitoring and predicting various fault conditions in Pressurized Water nuclear Reactor power plants, including reactor coolant flow and temperature variations, deviations from nominal working...
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Novel Investigation of Higher Order Spectral Technologies for Fault Diagnosis of Motor-Based Rotating Machinery
PublicationIn the last decade, research centered around the fault diagnosis of rotating machinery using non-contact techniques has been significantly on the rise. For the first time worldwide, innovative techniques for the diagnosis of rotating machinery, based on electrical motors, including generic, nonlinear, higher-order cross-correlations of spectral moduli of the third and fourth order (CCSM3 and CCSM4, respectively), have been comprehensively...
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Fast Real-Time RDFT- and GDFT-Based Direct Fault Diagnosis of Induction Motor Drive
PublicationThis paper presents the theoretical analysis and experimental verification of a direct fault harmonic identification approach in a converter-fed electric drive for automated diagnosis purposes. On the basis of the analytical model of the proposed real-time direct fault diagnosis, the fault-related harmonic component is calculated using recursive DFT (RDFT) and Goertzel DFT (GDFT), applied instead of the full spectrum calculations...
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Noninvasive method for rotor fault diagnosis in inverter fed induction motor drive
PublicationThis article presents a proposal, simulation and experimental results of a noninvasive rotor fault diagnosis method for the inverter fed induction motor drive. Comparing to reported methods the proposed one does not require any load, rotor brake, slip, mechanical or electrical system physical modification e.g. machine disassembly and can be applied regardless the rotor speed measurement or estimation method.
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Using an IEEE1149.1 Test Bus for Fault Diagnosis of Analog Parts of Electronic Embedded Systems
PublicationThe new solution of a BIST called the JTAG BIST for self-testing of analog parts of electronic embedded systems is presented in the paper. The JTAG BIST consists of the BCT8244A and SCANSTA476 integrated circuits of Texas Instruments controlled via the IEEE 1149.1 bus. The BCT8244A is a scan test device with octal buffers, and the SCANSTA476 is a 12-bit ADC with 8 analog input channels. Self-testing approach is based on the fault...
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Variable‐fidelity modeling of antenna input characteristics using domain confinement and two‐stage Gaussian process regression surrogates
PublicationThe major bottleneck of electromagnetic (EM)-driven antenna design is the high CPU cost of massive simulations required by parametric optimization, uncertainty quantification, or robust design procedures. Fast surrogate models may be employed to mitigate this issue to a certain extent. Unfortunately, the curse of dimensionality is a serious limiting factor, hindering the construction of conventional data-driven models valid over...
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Modeling of Process of Maintenance of Transport Systems Telematics with Regard to Electromagnetic Interferences
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New Two-center Ellipsoidal Basis Function Neural Network for Fault Diagnosis of Analog Electronic Circuits
PublicationIn the paper a new fault diagnosis-oriented neural network and a diagnostic method for localization of parametric faults in Analog Electronic Circuits (AECs) with tolerances is presented. The method belongs to the class of dictionary Simulation Before Test (SBT) methods. It utilizes dictionary fault signatures as a family of identification curves dispersed around nominal positions by component tolerances of the Circuit Under Test...
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Flow Process Models for Pipeline Diagnosis
PublicationThis chapter examines the problem of modeling and parameterization of the transmission pipeline flow process. First, the base model for discrete time is presented, which is a reference for other developed models. Then, the diagonal approximation (AMDA) method is proposed, in which the tridiagonal sub-matrices of the recombination matrix are approximated by their diagonal counterparts, which allows for a simple determination of...
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Reliability and types of diagnosis in the process of diesel engine operation
PublicationThe article presents complexity of the problem concerning development of diagnosis with defined reliability by a diagnosing system (SDG) on technical condition of marine combustion engines, especially main engines. It was shown that development of the final diagnosis, the so-called initial operation diagnosis, on the operational usability (fDG on PEx) of a main engine in particular, is not possible without prior development of...
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Advanced Modeling of Management Processes in Information Technology
PublicationThis book deals with the issues of modeling management processes of information technology and IT projects while its core is the model of information technology management and its component models (contextual, local) describing initial processing and the maturity capsule as well as a decision-making system represented by a multi-level sequential model of IT technology selection, which acquires a fuzzy rule-based implementation...
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Decisional DNA for modeling and reuse of experiential clinical assessments in breast cancer diagnosis and treatment
PublicationClinical Decision Support Systems (CDSS) are active knowledge resources that use patient data to generate case specific advice. The fast pace of change of clinical knowledge imposes to CDSS the continuous update of the domain knowledge and decision criteria. Traditional approaches require costly tedious manual maintenance of the CDSS knowledge bases and repositories. Often, such an effort cannot be assumed by medical teams, hence...
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Optimal asynchronous estimation of 2D Gaussian-Markov processes
PublicationW artykule rozważa się problem estymacji trajektorii dwuwymiarowych ciągłoczasowych procesów Gaussa-Markowa na podstawie zaszumionych pomiarów wykonywanych w nierównomiernie rozłożonych chwilach czasu. W przypadku takiego problemu, w każdym cyklu pracy algorytmu należy dokonać dyskretnoczasowej predykcji (analogicznie jak w przypadku filtru Kalmana). Niestety zadanie to może być złożone obliczeniowo. Aby rozwiązać ten problem,...
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Fault diagnosis of marine 4-stroke diesel engines using a one-vs-one extreme learning ensemble
PublicationThis paper proposes a novel approach for intelligent fault diagnosis for stroke Diesel marine engines, which are commonly used in on-road and marine transportation. The safety and reliability of a ship's work rely strongly on the performance of such an engine; therefore, early detection of any type of failure that affects the engine is of crucial importance. Automatic diagnostic systems are of special importance because they can...
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Fault diagnosis of analog piecewise linear circuits based on homotopy
PublicationArtykuł opisuje weryfikację metodą diagnostyki analogowych układów odcinkowo-liniowych opartą na podejściu homotopijnym. Homotopia przekształca jedną funkcję f(x) w inną funkcję g(x) poprzez zmianę parametru homotopii tî[0,1]. Ścieżka homotopijna pokazuje drogę od punktu x0 z dziedziny funkcji f(x) do odpowiadającego mu punktu x* funkcji g(x). Idea metody zakłada wykorzystanie funkcji f(x) do opisu diagnozowanego układu w stanie...
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A CUSUM-Based Approach for Condition Monitoring and Fault Diagnosis of Wind Turbines
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An application of the TCRBF neural network in multi-node fault diagnosis method
PublicationPrzedstawiono nową metodę samo-testowania części analogowej w systemach elektronicznych sterowanych mikrokontrolerami. Układ badany pobudzany jest przebiegiem sinusoidalnym przez generator zamontowany w systemie, a jego odpowiedź jest próbkowana w wybranych węzłach przez wewnętrzny przetwornik A/C mikrokontrolera. Detekcja i lokalizacja uszkodzenia jest dokontwana przez sieć neuronową typu TCRBF. Procedurę diagnostyczną zaimplementowano...
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A method of fault diagnosis of analog parts of electronic embedded systems with tolerances
PublicationPrzedstawiono nową metodę detekcji i lokalizacji uszkodzeń w częściach analogowych z tolerancjami elementów nieuszkodzonych mieszanych sygnałowo elektronicznych systemów wbudowanych sterowanych mikrokontrolerami. Metoda składa się z trzech etapów. W pierwszym etapie tworzony jest słownik uszkodzeń przez aproksymację rodziny pasów lokalizacyjnych. W etapie pomiarowym wewnętrzny licznik mikrokontrolera mierzy czasy trwania impulsów...
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A neural network based system for soft fault diagnosis in electronic circuits
PublicationW artykule przedstawiono system do diagnostyki uszkodzeń parametrycznych w układach elektronicznych. W systemie zaimplementowano słownikową metodę lokalizacji uszkodzeń, bazującą na pomiarach w dziedzinie częstotliwości przeprowadzanych za pomocą analizatora transmitancji HP4192A. Rozważono główne etapy projektowania systemu: definiowanie modelu uszkodzeń, wybór optymalnych częstotliwosci pomiarowych, ekstrakcję cech diagnostycznych,...
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Removal of Volatile Organic Compounds (VOCs) from Air: Focus on Biotrickling Filtration and Process Modeling
PublicationBiotrickling filtration is a well-established technology for the treatment of air polluted with odorous and volatile organic compounds (VOCs). Besides dozens of successful industrial applications of this technology, there are still gaps in a full understanding and description of the mechanisms of biotrickling filtration. This review focuses on recent research results on biotrickling filtration of air polluted with single and multiple...
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Improving peak detection by Gaussian mixture modeling of mass spectral signal
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Modeling of Surface Roughness in Honing Processes by UsingFuzzy Artificial Neural Networks
PublicationHoning processes are abrasive machining processes which are commonly employed to improve the surface of manufactured parts such as hydraulic or combustion engine cylinders. These processes can be employed to obtain a cross-hatched pattern on the internal surfaces of cylinders. In this present study, fuzzy artificial neural networks are employed for modeling surface roughness parameters obtained in finishing honing operations. As...
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Thermodynamic modeling of combustion process of the internal combustion engines – an overview
PublicationThe mathematical description of combustion process in the internal combustion engines is a very difficult task, due to the variety of phenomena that occurring in the engine from the moment when the fuel-air mixture ignites up to the moment when intake and exhaust valves beginning open. Modeling of the combustion process plays an important role in the engine simulation, which allows to predict incylinder pressure during the combustion,...
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Fault Tree Analysis and Failure Diagnosis of Marine Diesel Engine Turbocharger System
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Diagnosis of fully differential circuits based on a fault dictionary implemented in the microcontroller systems
PublicationPrzedstawiono nową koncepcję testera wbudowanego bist przeznaczonego do diagnostyki w pełni różnicowych układów analogowych implementowanych w mikrosystemach mieszanych sygnałowo. w trakcie testowania mierzona jest amplituda i faza wyjściowego napięcia różnicowego. procedura detekcji i lokalizacji uszkodzeń bazuje na słowniku uszkodzeń przechowywanym w pamięci programu mikrokontrolera. korzystną cechą przestrzeni pomiarowej wyznaczonej...
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On fault diagnosis of analogue electronic circuits based on transformations in multi-dimensional spaces.
PublicationPrzedstawiono ideę nowej klasy metod diagnostycznych opartej na przekształceniu transformującym zmiany parametru układu na krzywe identyfikacyjne w przestrzeniach wielowymiarowych. Rozszerzono również klasę tych metod na diagnostykę uszkodzeń wielokrotnych. Dla takich metod omówiono algorytm lokalizacji i identyfikacji pojedynczych i wielokrotnych uszkodzeń parametrycznych w liniowych układach elektronicznych. Przedstawiono rezultaty...
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Signal Partitioning Algorithm for Highly Efficient Gaussian Mixture Modeling in Mass Spectrometry
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Knowledge-Based Virtual Modeling and Simulation of Manufacturing Processes for Industry 4.0
PublicationABSTRACT Industry 4.0 aims at providing a digital representation of a production landscape, but the challenges in building, maintaining, optimizing, and evolving digital models in inter-organizational production chains have not been identified yet in a systematic manner. In this paper, various Industry 4.0 research and technical challenges are addressed, and their present scenario is discussed. Moreover, in this article, the novel...
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Numerical modeling of quantum dynamical processes
PublicationIn this dissertation I present a high-precision (15, 18 or 33 decimal places) C++ implementation of quantum dynamics time propagation algorithms for both time-independent and time-dependent Hamiltonian with an inhomogeneous source term. Moreover I present an extension of both algorithms for time propagation to handle arbitrary number of coupled electronic levels. I have performed a careful validation of these implementations comparing...
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Condition monitoring and fault diagnosis of wind turbines based on structural break detection in SCADA data
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Fault diagnosis in electronic circuits based on bilinear transformation in 3-D and 4-D spaces
PublicationPrzedstawiono ideę nowych metod diagnostycznych 3-D i 4-D opartych na przek-ształceniu biliniowym. Metody te bazują na transformacjach operujących odpo-wiednio w trzy i czterowymiarowych przestrzeniach funkcji układowych. Dlatych metod omówiono algorytm lokalizacji i identyfikacji pojedynczych uszko-dzeń parametrycznych w liniowych układach elektronicznych oraz algorytm lo-kalizacji i identyfikacji pojedynczych uszkodzeń...
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Modeling and Simulation Method of Precision Grinding Processes
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Using a square-wave signal for fault diagnosis of analog parts of mixed-signal electronic embedded systems
PublicationArtykuł przedstawia nowe podejście do detekcji i lokalizacji pojedynczych katastroficznych i parametrycznych uszkodzeń części analogowych w mieszanych sygnałowo elektronicznych systemach wbudowanych. Podejście składa się z trzech etapów: tworzenia słownika uszkodzeń na podstawie krzywych identyfikacyjnych, etapu pomiarowego w którym układ badany pobudzany jest falą prostokątną generowaną przez mikrokontroler a odpowiedź jest próbkowana...
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Production of process water using integrated membrane processes
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Modeling of the process of selected fire signaling systems
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A fault diagnosis method for analog parts of embedded systems based on time response and identification curves in the 3-D space
PublicationPrzedstawiono nową wersję 3-D nowej metody diagnostycznej części analogowych w mieszanych sygnałowo systemach wbudowanych bazujących na mikrokontrolerach. Bazuje ona na krzywych identyfikacyjnych w przestrzeni 3-D i pomiarze próbek napięcia odpowiedzi układu badanego na pobudzenie impulsem prostokątnym. Zalety metody: pomiary są wykonywane wyłącznie za pomocą urządzeń peryferyjnych popularnych mikrokontrolerów, procedura diagnostyczna...
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Teaching Methodology of Diagnosis Process on the Example of Intrusion and Hold-Up Alarm System
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PHYSICAL MODEL OF ENERGY-RELATED PROCESSES IN A ROTATING MECHANICAL SYSTEM FOR THE PURPOSES OF DIAGNOSIS OF TRANSMISSION SHAFTS
PublicationIn the present article, selected problems connected with identification of slowly changing energy-related processes accompanying high cyclic fatigue of construction materials of simple mechanical systems, with special consideration of transmission shafts, are mentioned for diagnostic purposes. The article also presents physical models of object and processes that in a simplified way reflect mechanical energy transmission from transmission...
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Diffusion process modeling by using fractional-order models
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Modeling of medium flow processes in transportation pipelines - the synthesis of their state-space models and the analysis of the mathematical properties of the models for leak detection purposes
PublicationThe dissertation concerns the issue of modeling the pipeline flow process under incompressible and isothermal conditions, with a target application to the leak detection and isolation systems. First, an introduction to the model-based process diagnostics is provided, where its basic terminology, tools, and methods are described. In the following chapter, a review of the state of the art in the field of leak detection and isolation...
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Modeling of production planning and control process consistent with theory of constraint
PublicationArtykuł dotyczy problematyki zastosowania metody werbel-bufor-lina do planowania produkcji w systemach produkcyjnych z wielokrotnymi buforami. W artykule przedstawiono algorytm - jego funkcje, dane wejściowe i wyjściowe - który może mieć zastosowanie do modelowania procesu planowania i sterowania produkcją. Algorytm umożliwia określenie wielkości czasowych buforów w systemie oraz terminów rozpoczęcia i zakończenia realizacji zadań....
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Application of Generalized Regression Neural Network and Gaussian Process Regression for Modelling Hybrid Micro-Electric Discharge Machining: A Comparative Study
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Application of theory of semi-Markov processes to determining distribution of probabilistic process of marine accidents resulting from colission of ships
PublicationIn this paper is presented possible application of the theory of semi-Markov processes to elaborating an eight-state model of the process of occurrence of serviceability state and unserviceability states of sea-going ships making critical manoeuvres during their entering and leaving the ports. In the analysis it was taken into account that sea-going ships are in service for a very long time t (t → ∞). The model was elaborated to...
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Green`s function methods for Mathematical modeling of unidirectional diffusion process in isothermal metals bonding process
PublicationPodano wykorzystanie funkcji Greena w rozwiązaniu matematycznego modelu dyfuzji jednowymiarowej podczas izotermicznego łączenia metali.
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Choosing Exploration Process Path in Data Mining Processes for Complex Internet Objects
PublicationWe present an experimental case study of a novel and original framework for classifying aggregate objects, i.e. objects that consist of other objects. The features of the aggregated objects are converted into the features of aggregate ones, by use of aggregate functions. The choice of the functions, along with the specific method of classification can be automated by choosing of one of several process paths, and different paths...
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Choosing Exploration Process Path in Data Mining Processes for Complex Internet Objects
PublicationWe present an experimental case study of a novel and original framework for classifying aggregate objects, i.e. objects that consist of other objects. The features of the aggregated objects are converted into the features of aggregate ones, by use of aggregate functions. The choice of the functions, along with the specific method of classification can be automated by choosing of one of several process paths, and different paths...
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Process modeling inside cylinder in an internal combustion engine with heat regeneration
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Modeling of Heat Source Based on Parameters of Electron Beam Welding Process
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Applications of the artificial intelligence methods for modeling of the ACAlSi7Cu alloy crystallization process
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Modeling the debonding process of osseointegrated implants due to coupled adhesion and friction
PublicationCementless implants have become widely used for total hip replacement surgery. The long-term stability of these implants is achieved by bone growing around and into the rough surface of the implant, a process called osseointegration. However, debonding of the bone–implant interface can still occur due to aseptic implant loosening and insufficient osseointegration, which may have dramatic consequences. The aim of this work is to...