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Search results for: ELECTRIC DRIVES, POWER CONVERTERS, CONTROL SYSTEMS
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ARCHITECTURE OF HYDROPOWER PLANTS IN POMORZE
PublicationThe history of energetic use of the rivers of Pomerania (Pomorze) is traced from the late Middle Ages. Their potential due to geographical specificity of the region was still attractive in the era of electricity of the19th and the first half of the 20th century. Configuration of the terrain, geological, and natural restrictions, but mainly energetic potential of particular localization were crucial for economical success of the...
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Voltage Transients Transfer over Medium Voltage Instrument Transformers
PublicationThis paper presents voltage harmonic transfer accuracy problems through voltage transformers which are used in power quality monitoring systems in medium and high voltage grids. A simplified lumped parameters circuit model of the voltage transformer is proposed and verified by simulation and experimental investigations. A number voltage transformers typically used in medium voltage grid has been tested in the conducted disturbances...
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Voltage Harmonics Transfer through Medium Voltage Instrument Transformers
PublicationVoltage transformers are widely used in power quality monitoring systems in medium and high voltage grids. This paper presents accuracy problems related to voltage harmonics transfer through instrument transformers. A simplified lumped-parameters wideband circuit model of the voltage transformer is proposed and verified by simulation and experimental investigations. A number of voltage transformers have been tested in the frequency...
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Bezpieczeństwo elektroenergetyczne dla pokoleń
PublicationW artykule przeanalizowano źródła energii pierwotnej, ich wystarczalnośći dywersyfikację w skali lokalnej i globalnej, problem dekarbonizacji polskiej elektroenergetyki na tle europejskiej polityki klimatycznej, osiągalność źródeł gazu jako efektywnego paliwa dla energetyki, polski program energetyki jądrowej, bezpieczeństwo zasilania elektrycznych systemów trakcyjnych jako strategicznej alternatywy...
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Strength analysis of a large-size supporting structure for an offshore wind turbine
PublicationThe offshore wind power industry is the branch of electric energy production from renewable sources which is most intensively developed in EU countries. At present, there is a tendency to install larger-power wind turbines at larger distances from the seashore, on relatively deep waters. Consequently, technological solutions for new supporting structures intended for deeper water regions are undergoing rapid development now. Various...
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The impact of the AC922 Architecture on Performance of Deep Neural Network Training
PublicationPractical deep learning applications require more and more computing power. New computing architectures emerge, specifically designed for the artificial intelligence applications, including the IBM Power System AC922. In this paper we confront an AC922 (8335-GTG) server equipped with 4 NVIDIA Volta V100 GPUs with selected deep neural network training applications, including four convolutional and one recurrent model. We report...
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Pipeline System for Heat Transportation from Nuclear Power Plant – an Optimizing Approach
PublicationOver the last few years heat piping insulation technology and pump systems efficiency have been significantly improved. Reduced thermal losses encourage heat transportation over long distances. It provides an opportunity for increasing thermodynamic efficiency of Nuclear Power Plants (NPPs) that are often located in rural areas because of safety issues. It can be achieved by Combined Heat and Power (CHP) generation, as heat produced...
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Determination of Mechanical Energy Loss in Steady Flow by Means of Dissipation Power
PublicationWhen systems of simple geometry like pipes or regular channels are considered, the mechan- ical energy loss of the fluid flow can be expressed by local and longitudinal empirical energy loss coefficients. However, in the case of large spatially distributed objects, there are no simple approaches to this task. In practice, general recommendations addressing different types of objects are used, but they usually provide very coarse...
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Challenges in operating and testing loop heat pipes in 500–700 K temperature ranges
PublicationThe potential applications of loop heat pipes (LHPs) are the nuclear power space systems, fuel cell thermal management systems, waste heat recovery systems, medium temperature electronic systems, medium temperature military systems, among others. Such applications usually operate in temperature ranges between 500–700 K, hence it is necessary to develop an LHP system that will meet this requirement. Such a thermal management device...
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Fuzzy logic in controlling flexible manufacturing cell
PublicationIn the present work a controlling method based on fuzzy rule base is proposed. Practical approaches are developed and focused on real time problems related to flexible manufacturing cell. Techniques for design and implementation of fuzzy systems in the framework of control production and quality states are presented. Keywords: controlling, manufacturing system, fuzzy logic, turning, burnishingW artykule przedstawiono propozycję...
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Framework for RIDM within functional safety management process
PublicationThe functional safety management in life cycle is a complex process starting with identifying hazards and defining safety-related functions (SRFs) with risk assessment oriented at determining the safety integrity level. Another element of such life cycle is a verification of required SIL for designed safety-related system which implements safety function. Due to complexity of the problem, to overcome difficulties in safety-related...
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Reliable Document-Centric Processing in Loosely Coupled Email-Based Systems
PublicationEmail is a simple way to exchange digital documents of any kind. The Mobile INteractive Document architecture (MIND) enables self-coordination and self-steering of document agent systems based on commonly available email services. In this paper, a mechanism for providing integrity and reliability of such an email based agent system is proposed to cope with message soft or hard bounces, user interrupts, and other unexpected events....
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Polityka i porządek prawny w polskiej energetyce na tle polityki Unii Europejskiej
PublicationW artykule przeanalizowano rozwój wspólnotowego rynku energii elektrycznej, polityk ę energetyczną Polski i UE, sytuację i działania Polski na wspólnotowym rynku energii elektrycznej, a następnie przeanalizowano nowe regulacje prawne dla współpracy rozproszonych źródeł energii elektrycznej i sieci inteligentnych z systemem krajowym, dla zwrotu energii odzyskiwanej z systemów elektromechanicznych do zasilającej...
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Chitosan, Collagen and Gelatin in the design of novel materials with antimicrobial acticity
PublicationMedical devices containing and releasing antiinfective agents directly on the site of injury are a common group of materials available and widely used in treating difficult to heal wounds. Sustained contact of the active agent to the damaged tissue, needed to inhibit infection and preservation of microbiological purity of the wound, is provided by the immobilization antimicrobial agents on the surface of the matrix material or...
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Comparative Study of Balancing SRT by Using Modified ASM2d in Control and Operation Strategy at Full-Scale WWTP
PublicationDetailed knowledge on the composition of the influent going into the wastewater treatment system is essential for the development of a reliable computer model. In the context of WWTPs (wastewater treatment plants), the wastewater characteristics are not only important for activated sludge system modelling, but also have an impact on the appropriate control of single unit operations. The aim of this study was to evaluate the concepts...
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Research on Linear Actuators for Active Foil Bearings
PublicationActive foil bearings are a kind of gas foil bearing. They contain actuators which allow for modification of the bearing sleeve size and the shape of the lubrication gap. Rotor vibrations can be actively controlled by these changes. It is possible, among other things, to reduce the starting torque, control the vibration amplitude at different speeds and improve operational safety. Prototypes of active foil bearings are being developed...
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Safety integrity level verification for safety-related functions with security aspects
PublicationThe article is devoted some important issues of the functional safety analysis, in particular the safetyintegrity level (SIL) verification of safety functions to be implemented within the distributed controland protection systems with regard to cyber security aspects. The procedure for functional safety man-agement includes hazard identification, risk analysis and assessment, specification of overall safetyrequirements and definition...
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Low cost set-up for supercapacitors parameters evaluation
PublicationSupercapacitors are capable to store relatively high amount of energy comparing to its mass. Growing number of these devices applications requires development of new testing methods. Standard methods of evaluation of supercapacitor parameters, as cycling voltammetry, CV, galvanostatic cycling with potential limitation, GCPL, impedance measurements, require equipment of high cost...
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Contr-rotating eccentric-mass rotors used as exciters of sinusoidal forces applied to elastically supported bodies
PublicationThe work focuses on aspects of multibody dynamics. Investigated object is a mass driven by rotations of an inertial shaker. Resulting vibrational set consists of two counter-rotating identically-unbalanced rotors. Since the mass centres of the rotors do not coincide with the axes of their rotations, significant centrifugal forces arise during rotations. As both rotors are identically unbalanced, the inter-axial force components...
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APPLICATION OF VORTEX FLOW MODEL IN PROPELLER-STATOR SYSTEM DESIGN AND ANALYSIS
PublicationThe paper covers basics of the vortex model used for propeller-stator systems. The outline of the design algorithm is given and the results of its application are shown. The designed propeller-stator system was the subject of model tests run at the CTO model basin and cavitation tunnel. Stator’s influence on the delivered power required by the propeller and its revolution rate has been examined by conducting self-propulsion...
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WATER LUBRICATED MAIN SHAFT BEARINGS - MODERN SOLUTION FOR HYDROPOWER INDUSTRY - Experimental and theoretical studies
PublicationWater-lubricated bearings are finding increasingly wide use in various branches of industry. As such, they may also be encountered in hydro power industry. They are also increasingly frequently employed in bearing systems of marine shaft propulsions and water pumps [1]. This rising popularity is due to a number of reasons [2]. First of all, their simple construction has direct impact on the level of pricing which is usually quite...
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The dynamic performance analysis of the Micro-turbine's rotor supparted on slide and roling element bearings
PublicationThis article presents the results of investigations of dynamic characteristics of a small-dimension rotor with slide and rolling element bearings. The object of investigations was the rotor-bearing system designed for the ORC based low-power steam micro-turbine. The investigations were performed using MESWIR series programs, as well as commercial FEA software ABAQUS and MADYN 2000. The results of modal analysis of the micro-rotor...
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Affective Learning Manifesto – 10 Years Later
PublicationIn 2004 a group of affective computing researchers proclaimed a manifesto of affective learning that outlined the prospects and white spots of research at that time. Ten years passed by and affective computing developed many methods and tools for tracking human emotional states as well as models for affective systems construction. There are multiple examples of affective methods applications in Intelligent Tutoring Systems (ITS)....
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Heterogeneity of national accounting systems, world-class universities and financial resources: What are the links?
PublicationThis study investigates the relationship between university financial resources, applied accounting systems, and the place of a university in the Shanghai Ranking. We find a strong relationship between the financial resources under the control of a world-class university and the position of that university in the highest tier of the global ranking. We propose a model (available online) to predict a university’s tier in the ranking...
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The impact of shipping 4.0 on controlling shipping accidents: A systematic literature review
PublicationMaritime shipping, with a significant role in global trade, confronts various accidents leading to loss of lives, properties, and the environment. Shipping 4.0 technologies are scaling up to address this problem by employing real-time data-driven technologies, including cyber-physical systems, advanced tracking and tracing, intelligent systems, and big data analytics. Despite growing attention, there is a general lack of clarity...
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Quantitative assessment
PublicationThe main trends in the development of analytical chemistry are the determination of increasingly lower concentrations of analytes in samples with complex matrix composition (trace analysis). While the obtained analytical results must be reliable, which means that they must accurately (truly and precisely) reflect the actual content of analytes in a representative sample of the material object under study. However, it is an extremely...
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Knowledge-based functional safety management using ProSIL software
PublicationIn the article the ProSIL software for computer aided functional safety management is presented. The software consists of three modules for the determination of the required SIL level (ProSILen) and verification of the SIL level (ProSILver). In the ProSIL the calibrated knowledge-based risk graph method for determining the required safety integrity level (SIL) of the safety functions identified in hazard analysis is implemented....
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Human Factors and Functional Safety Analysis in Designing the Control Rooms of Industrial Hazardous Plants
PublicationIn this work some aspects of human factors and functional safety analysis in designing the control rooms of industrial hazardous plants are presented. The “defence in depth” (D-in-D) concept is outlined. Some designing issues of the alarm system (AS) with regard to human factors to be supported using the human reliability analysis (HRA) are discussed. The AS and decision support system (DSS), when properly designed, would contribute...
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AN ENERGY APPROACH TO THE FATIGUE LIFE OF SHIP PROPULSION SYSTEMS
PublicationThe conducted research investigations aimed to carry out an identification of the constructional materials fatigue state of the ship propulsions’ rotational mechanical units for diagnostic purposes. The fatigue cracks of the elements transmitting mechanical energy streams from the propulsion engines to the ship propellers or to the generators of the ship’s electric power station stand for a primary reason for the secondary, usually...
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Image Representation for Cognitive Systems Using SOEKS and DDNA: A Case Study for PPE Compliance
PublicationCognitive Vision Systems have gained significant interest from academia and industry during the past few decade, and one of the main reasons behind this is the potential of such technologies to revolutionize human life as they intend to work under complex visual scenes, adapting to a comprehensive range of unforeseen changes, and exhibiting prospective behavior. The combination of these properties aims to mimic the human capabilities...
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Influence and development of new kinematic systems in flat surface lapping
PublicationThe face grinding and lapping technology is widely used in the field of the precise and ultraprecise manufacturing. It has become an indispensable technology in the manufacture of many parts. An absence of material restrictions allows machining both metal and non-metallic materials, including technical ceramics [1]. Nowadays there are mainly two kinematic systems in lapping machines [2]. The machining plane-parallel surfaces is...
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Computational analysis of power-law fluids for convective heat transfer in permeable enclosures using Darcy effects
PublicationNatural convection is a complex environmental phenomenon that typically occurs in engineering settings in porous structures. Shear thinning or shear thickening fuids are characteristics of power-law fuids, which are non-Newtonian in nature and fnd wide-ranging uses in various industrial processes. Non-Newtonian fuid fow in porous media is a difcult problem with important consequences for energy systems and heat transfer. In this...
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Feasibility of combined diesel engine - steam turbine in power station operating in the maritime
PublicationCompression-ignition engines used in ship technology as main propulsion engines are large units reaching even to 50-60 MW. Currently, the efficiency of such engines amounts to 45-50%. With such a large power unit, exhaust gases leaving the engine contain very large quantities of heat available for further treatment. Exhaust gases from the piston engine contain about 25% of the heat supplied to the engine in the fuel. Using the...
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Energy-Aware Scheduling for High-Performance Computing Systems: A Survey
PublicationHigh-performance computing (HPC), according to its name, is traditionally oriented toward performance, especially the execution time and scalability of the computations. However, due to the high cost and environmental issues, energy consumption has already become a very important factor that needs to be considered. The paper presents a survey of energy-aware scheduling methods used in a modern HPC environment, starting with the...
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High-efficiency mini and micro heat exchangers for dispersed power generation
PublicationTaking into account the dispersed systems technologies and their development, the ORC systems seem to be promising technology amongst various micro-CHP domestic units (electrical power production below 10 kWe), however practical realization of the ORC cycle in a micro-scale is technically challenging. The system consists in devices such as the vapour generation unit (boiler), expansion device and heat exchangers. Each of them should...
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Adaptacyjny system oświetlania dróg oraz inteligentnych miast
PublicationPrzedmiotem rozprawy jest zbadanie praktycznej możliwości wykrywania w czasie rzeczywistym anomalii w systemie oświetlenia drogowego w oparciu o analizę danych ze inteligentnych liczników energii. Zastosowanie inteligentnych liczników energii elektrycznej (Smart Meter) w systemach oświetlenia drogowego stwarza nowe możliwości w zakresie automatycznej diagnostyki takich niepożądanych zjawisk jak awarie lamp, odstępstwa od harmonogramu...
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Local dynamics of fluids and dielectrics as the foundation of signal-carrying wave properties
PublicationThis paper develops an original approach to fundamental problems of classical linear acoustics and electromagnetics, proving a crucial role of doubly-dynamic local properties of a propagation medium in supporting wave-like fields able to carry information signals. The proof is composed of two steps concerning, subsequently, fluid acoustics and dielectric electromagnetics. The first step consists in complementing a common, practically...
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Synergistic effects of a swirl generator and MXene/ water nanofluids used in a heat exchanger pipe of a negative CO2 emission gas power plant
Publicationfocus on optimizing heat exchangers contributes to improved temperature control mechanisms, ensuring the sustainable operation of innovative power plants working towards negative CO2 emissions. In the realm of oxy-combustion within Negative CO2 Emission Power Plants (nCO2PP), the temperature of combustion products surpasses 3000 (K). Addressing this challenge, the imperative arises to reduce these elevated temperatures to a manageable...
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Agents in Simulation of Cyberattacks to Evaluate Security of Critical Infrastructures
PublicationIn the last years critical infrastructures have become highly dependent on the information technologies and exposed to cyberattacks. Because the effects of the attacks can be detrimental, it is crucial to comprehensively asses the security of the infrastructures' information systems. This chapter describes MAlSim - the simulator of malicious software based on software agents, developed for the needs of a testbed for critical infrastructures...
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Three-dimensional Web Geographic Information System using web-based technologies
PublicationWeb-based Geographic Information Systems offer a way of delivering geographic information to devices with small computational power, such as smartphones. In recent years, the rapid development of the Web Graphics Library (WebGL) made it possible to create rich interactive applications running inside a web browser and displaying three-dimensional objects using hardware acceleration. This paper presents a three-dimensional Web-GIS...
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Detection Range of Intercept Sonar for CWFM Signals
PublicationStealth in military sonars applications may be ensured through the use of low power signals making them difficult to intercept by the enemy. In recent years, silent sonar design has been investigated by the Department of Marine Electronic Systems of the Gdansk University of Technology. This article provides an analysis of how an intercept sonar operated by the enemy can detect silent sonar signals. To that end a theoretical intercept...
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Możliwości zastosowania zasobnikowych jednostek trakcyjnych na liniach kolejowych na przykładzie Pomorskiej Kolei Metropolitalnej
PublicationW artykule zwrócono uwagę, że zasobniki stosowane głównie do rekuperacji energii, mogą być również wykorzystane do zasilania pociągów na niezelektryfikowanych i zelektryfikowanych odcinkach linii kolejowych. Innowacyjność tego rozwiązania wykazano na podstawie dwóch aplikacji kolejowych elektrycznych zasobnikowych jednostek trakcyjnych: pierwszej funkcjonującej od 2014 roku na linii Utsunomiya – Karasuyama w Japonii oraz drugiej,...
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Smart Knowledge Engineering for Cognitive Systems: A Brief Overview
PublicationCognition in computer sciences refers to the ability of a system to learn at scale, reason with purpose, and naturally interact with humans and other smart systems, such as humans do. To enhance intelligence, as well as to introduce cognitive functions into machines, recent studies have brought humans into the loop, turning the system into a human–AI hybrid. To effectively integrate and manipulate hybrid knowledge, suitable technologies...
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Integrating conventional nitrogen removal with anammox in wastewater treatment systems: Microbial metabolism, sustainability and challenges
PublicationThe various forms of nitrogen (N), including ammonium (NH4+), nitrite (NO2−), and nitrate (NO3−), present in wastewaters can create critical biotic stress and can lead to hazardous phenomena that cause imbalances in biological diversity. Thus, biological nitrogen removal (BNR) from wastewaters is considered to be imperatively urgent. Therefore, anammox-based systems, i.e. partial nitrification and anaerobic ammonium oxidation (PN/anammox)...
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Quality assurance of alcoholic beverages by electronic nose
PublicationQuality is very important attribute of every alcoholic beverage. It is very significant to satisfy consumers and assure food quality. Flavour, colour and taste constitute a great matter not only for connoisseurs. Due to these features, the whole manufacturing process need to be monitored. This paper presents a high-class devices useful in assessing of beverage quality. Electronic noses offer quick real-time analysis, which is very...
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Developing Prognostic Models of Organization Evolution
PublicationThe work focuses on the problem of measuring evolution of IT organizations. Changes in business influence functioning of the IT organization. IT departments or companies must ensure that the needs of their parent company/customers will be met. Therefore they must constantly evolve. Following question can be raised: is it possible to support process of changes the IT organization to run it smoother, faster, easier but with reduced...
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RESIDUE ANALYSIS OF ETU AND PTU BY LC/MS
PublicationDithiocarbamates (DTCs) are important organosulfur compounds, which act as inhibitors of metal dependant and sulphydryl enzymes and have a serious consequence on biological systems. They possess variety of applications in agriculture as fungicides, as well as, in the rubber industry as vulcanization accelerators and antioxidants. In this way, DTCs are the main group of fungicides used to control approximately 400 pathogens of more...
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Arm EMG Wavelet-Based Denoising System
PublicationThese paper presents research results of muscle EMG signal denoising. In the same time two muscles were examined - an adductor muscle (biceps brachii) and an abductor muscle (tricpeps brachii). The EMG signal was filtered using the wavelet transform technique, having selected the crucial parameters as: wavelet basis function (Daubechies 4), 10 th decomposition level, threshold selection algorithm (Heurestic) and a sln rescaling...
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Robust Parameter Estimation and Output Prediction for Reactive Carrier-Load Nonlinear Dynamic Networks
PublicationIn this paper an extension of on-line model simplification technique for a class of networked systems, namely reactive carrier-load nonlinear dynamic networked system (RCLNDNS), kept within point-parametric model (PPM) framework is addressed. The PPM is utilised to acquire a piece wise constant time-varying parameter linear structure for the RCLNDNS suitable for the on-line one step ahead prediction that may be applied to monitoring...
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Analysis of data fusion algorithms for the vessel with the dynamic positioning system
PublicationThe dynamic positioning (DP) system on the vessel is operated to control the position and heading of the vessel with the use of propellers and thrusters installed on the board. On DP vessels redundant measurement systems of position, heading and the magnitude and direction of environmental forces are required for safety at sea. In this case, a fusion of data is needed from individual measurement devices. The article proposes a...