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Search results for: ENERGY SYSTEM OPTIMIZATION MODELS
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Design of modified PID controllers for 3D crane control
PublicationFrom the control viewpoint, 3D crane is a dynamic, nonlinear and multidimensional electromechanical system. In this paper, five control systems using a set-point weighted PID controllers (modified controllers) are designed. These structures and properties are presented. Optimization process of controllers settings based on integral performance indices is made. Simulation tests of control systems are presented. Comparison of integral...
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Advanced seismic control strategies for smart base isolation buildings utilizing active tendon and MR dampers
PublicationThis paper investigates the seismic behaviour of a five-storey shear building that incorporates a base isolation system. Initially, the study considers passive base isolation and employs a multi-objective archived-based whale optimization algorithm called MAWOA to optimize the parameters of base isolation. Subsequently, a novel model is proposed, which incorporates an interval type-2 Takagi-Sugeno fuzzy logic controller (IT2TSFLC)...
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MEASUREMENT AND ANALYSIS OF TRANSMISSION LOSSES IN THE SUPPLY SYSTEM OF ELECTRIFIED TRANSPORT
PublicationThe issue of electric energy saving in public transport is currently becoming a key area of interest, a fact connected with both an increase in society’s environmental awareness and a rise in the prices of fuel and electricity. Electricity can be saved by reducing transmission losses in the supply system. The article presents a method of measurement and analysis of transmission losses in the supply system of electrified public transport...
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The forming and emission of high power electromagnetic pulses
PublicationAn impulse energy source, a power conditioning system and an electromagnetic field emitter are essential to generate an electromagnetic field pulse (EMFP) with a specific frequency bandwidth. Selected simulation results for a power conditioning system consisting of a fuse opening switch and a paraboloidal electromagnetic emitter have been presented in this article. The synthetic system examined in the simulation is powered by...
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Numerical Analysis of Steady Gradually Varied Flow in Open Channel Networks with Hydraulic Structures
PublicationIn this paper, a method for numerical analysis of steady gradually varied fl ow in channel networks with hydraulic structures is considered. For this purpose, a boundary problem for the system of ordinary differential equations consisting of energy equation and mass conservation equations is formulated. The boundary problem is solved using fi nite difference technique which leads to the system of non-linear algebraic equations....
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ANALYSIS OF POSSIBILITIES FOR THE USE OF VOLUME-DELAY FUNCTIONS IN THE PLANNING MODULE OF THE TRISTAR SYSTEM
PublicationTravel time is a measure commonly used for traffic flow modelling and traffic control. It also helps to evaluate the quality of traffic control systems in urban areas. Traffic control systems that use traffic models to predict changes and disruptions in vehicle flows have to use vehicle speed-prediction models. Travel time estimation studies the effects of traffic volumes on a street section at an average speed. The TRISTAR Integrated...
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Uniform sampling in constrained domains for low-cost surrogate modeling of antenna input characteristics
PublicationIn this letter, a design of experiments technique that permits uniform sampling in constrained domains is proposed. The discussed method is applied to generate training data for construction of fast replacement models (surrogates) of antenna input characteristics. The modeling process is design-oriented with the surrogate domain spanned by a set of reference designs optimized with respect to the performance figures and/or operating...
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Novel structure and EM-driven design of miniaturized microstrip rat-race coupler
PublicationIn this paper, a novel structure and design procedure of a miniaturized microstrip rat-race coupler (RRC) is described. Small size of the RRC is achieved by folding the transmission lines of the conventional circuit into its interior, as well as by implementation of the structure on three layers. The final size of the coupler realized for the operating frequency of 1 GHz is only 220 mm2, which gives over 95% footprint reduction...
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Fast Full-Wave Multilevel Zero-Pole Optimization of Microwave Filters
PublicationA new concept is proposed for the full-wave computer-aided design of microwave filters. The method consists of two stages and operates on the zeros and poles of the transfer function and their derivatives. These quantities are evaluated from the response computed by a full-wave electromagnetic solver with two levels of accuracy. The two stages make use of different models that are optimized using a low-accuracy electromagnetic...
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The impact of lipophilicity on environmental processes, drug delivery and bioavailability of food components
PublicationLipophilic properties of the compound allow to predict its fate in living organisms and to propose the models of chemicals transport and accumulation in the ecosystem. Lipophilicity is also useful as the characteristic of chemicals in respect to their optimal attributes for specific biological and non-biological tasks. The lipophilicity descriptors define the potency of endo- and xenobiotics to metabolic transformations and their...
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Bismuth-based nanomaterials-assisted photocatalytic water splitting for sustainable hydrogen production
PublicationThe rapidly increase in the world's population has resulted in a corresponding increase in the energy demand. This demand is largely being met by fossil fuels for power generation, industrial fuel and transportation. However, due to the limited availability of fossil fuels and their negative effects on the environment. The use of fossil fuels results in by-products such as carbon, nitrogen and sulfur oxides which have negative...
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Bismuth-based nanomaterials-assisted photocatalytic water splitting for sustainable hydrogen production
PublicationThe rapidly increase in the world's population has resulted in a corresponding increase in the energy demand. This demand is largely being met by fossil fuels for power generation, industrial fuel and transportation. However, due to the limited availability of fossil fuels and their negative effects on the environment. The use of fossil fuels results in by-products such as carbon, nitrogen and sulfur oxides which have negative...
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Performance and Energy Aware Training of a Deep Neural Network in a Multi-GPU Environment with Power Capping
PublicationIn this paper we demonstrate that it is possible to obtain considerable improvement of performance and energy aware metrics for training of deep neural networks using a modern parallel multi-GPU system, by enforcing selected, non-default power caps on the GPUs. We measure the power and energy consumption of the whole node using a professional, certified hardware power meter. For a high performance workstation with 8 GPUs, we were...
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Evaluation of Street Lighting Efficiency Using a Mobile Measurement System
PublicationThe issue concerns the initial stage of work on a method for performing a rapid assessment of the energy efficiency and illuminance of a street lighting installation. The proposed method is based on simultaneous measurement of illuminance from three lux meters placed on the roof of the vehicle. The data are acquired in road traffic, while the vehicle is driving. The proposed solution will allow in the future to quickly and reproducibly...
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Photovoltaic-Installation Performance in Central Europe on the Example of Poland
PublicationThe amount of the electric energy obtained from a photovoltaic (PV) installation depends on the energy of the radiation. Weather conditions differ strongly between various years even in the same season. Depending on the climatic conditions of a given location, fixed PV solar plants as well as one-axis and dual-axis tracking PV solar plants are being installed worldwide. The aim of this work is to analyse the sunlight intensity...
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Pyrolysis of Waste Biomass: Technical and Process Achievements, and Future Development-A Review
PublicationPyrolysis has been applied in the human economy for many years, and it has become a significant alternative to the production of chemical compounds, including biofuels. The article fo-cuses mostly on recent achievements in the technical and processing aspects of pyrolysis. The aim of the review is to present the latest research on the process of waste biomass pyrolysis to fuel production. The paper describes the mechanisms of...
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Fatigue life prediction of notched components under size effect using strain energy reformulated critical distance theory
PublicationNotch and size effects show significant impact on the fatigue performance of engineering components, which deserves special attention. In this work, a strain energy reformulated critical distance theory was developed for fatigue life prediction of notched components under size effect. Experimental data of different notched specimens manufactured from GH4169, TC4, TC11 alloys and low carbon steel En3B were used for model validation...
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Modelling of the High Speed Multi-Pole Synchronous Generator for Application in More Electric Aircraft Power Systems
PublicationIn this paper different models of the synchronous generator are presented. The simulation results compared with the measurements are shown. Certain physical phenomena are included in described models for the porpoise of adequate analysis of the more electric aircraft power system. For different modelling levels, such as functional level or behavioural level, different physical phenomena have been included. Simulation results for...
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Regional quality contests based on business excellence models – Pomeranian case study
PublicationCompetitions based on models of organizational excellence have significant potential. Organizations participating in these initiatives have the chance not only to get marketing benefits, but also gain comprehensive knowledge about their management systems. Moreover, thanks to the structure of models of excellence an organization can plan in detail the improvement activities in its main processes. The aim of the authors is to analyze...
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Femtosecond Er-doped fiber laser source tunable from 872 to 1075 nm for two-photon vision studies in humans
PublicationWe report the development of a widely-tunable femtosecond fiber laser system and its application for two-photon vision studies. The source is based on an Er-doped fiber laser with spectral shift up to 2150 nm, followed by a second harmonic generation module to generate a frequency-doubled beam tunable from 872 to 1075 nm. The source delivers sub-230 fs pulses with nearly-constant duration over the entire tuning range, with output...
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Fault-tolerant performance of the novel five-phase doubly-fed induction generator
PublicationThe article presents the concept of a new design of a multi-phase doubly-fed induction generator (DFIG). The innovative design approach uses a five-phase power supply from the rotor side of the generator with a three-phase classic stator power supply. Modern three-phase doubly-fed induction generators are the dominant choice for Wind Energy Conversion Systems (WECS). Solutions of this type are sensitive to the loss of at least...
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Fast multi-objective design optimization of microwave and antenna structures using data-driven surrogates and domain segmentation
PublicationPurpose Strategies and algorithms for expedited design optimization of microwave and antenna structures in multi-objective setup are investigated. Design/methodology/approach Formulation of the multi-objective design problem oriented towards execution of the population-based metaheuristic algorithm within the segmented search space is investigated. Described algorithmic framework exploit variable fidelity modeling, physics- and...
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Generalized Formulation of Response Features for Reliable Optimization of Antenna Input Characteristics
PublicationElectromagnetic (EM)-driven parameter adjustment has become imperative in the design of modern antennas. It is necessary because the initial designs rendered through topology evolution, parameter sweeping, or theoretical models, are often of poor quality and need to be improved to satisfy stringent performance requirements. Given multiple objectives, constraints, and a typically large number of geometry parameters, the design closure...
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Computationally Efficient Surrogate-Assisted Design of Pyramidal-Shaped 3D Reflectarray Antennas
PublicationReflectarrays (RAs) have been attracting considerable interest in the recent years due to their appealing features, in particular, a possibility of realizing pencil-beam radiation patterns, as in the phased arrays, but without the necessity of incorporating the feeding networks. These characteristics make them attractive solutions, among others, for satellite communications or mobile radar antennas. Notwithstanding, available microstrip...
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Multi-factor fuzzy sets decision system forecasting consumer insolvency risk
PublicationThe objective of this study is to develop a multi-factor decision system predicting insolvency risk for natural persons with the use of fuzzy sets. Considering that the financial situation of households is affected by various endogenous and exogenous factors, the main assumption of this study is that the system for predicting financial difficulties should not be limited to the use of only a few financial variables concerning consumers,...
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Mobile Offloading Framework: Solution for Optimizing Mobile Applications Using Cloud Computing
PublicationNumber of mobile devices and applications is growing rapidly in recent years. Capabilities and performance of these devices can be tremendously extended with the integration of cloud computing. However, multiple challenges regarding implementation of these type of mobile applications are known, like differences in architecture, optimization and operating system support. This paper summarizes issues with mobile cloud computing and...
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HYBRID REDUCED MODEL OF ROTOR
PublicationIn the paper, the authors describe the method of model reduction of a rotor system. The proposed approach enables to obtain a low order model including e.g. nonproportional damping or the gyroscopic effect. This method is illustrated using the example of a rotor system. First, a model of the system was built without gyroscopic and damping effects by using the rigid finite element method. Next, this model was reduced. Finally, two...
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Koncepcja i symulacja polowa generatora o zmiennej częstotliwości. Zastosowanie w autonomicznych systemach elektroenergetycznych = Conception and field simulations of a variable frequency generator. Application for autonomous power generation system
PublicationStreszczenie angielskie: This paper covers a conception and simulation results for a brushless synchronous generator working with variable speed in an autonomous energy generation system (e.g. airplane power grid, hybrid vehicle, micro-CHP). The papers has two parts: presentation of the generator conception used in modern autonomous energy generation systems, and simulation results using filed model elaborated in Flux2D software....
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Power Surge Compensator based on a Four Level Diode Clamped Inverter for ship application. Average model
PublicationPaper presents continuous average value model of Power Surge Compensator based on a Four Level Diode Clamped Inverter with super capacitor as a energy storage device. This conditioner is design for power surge or fluctuation elimination, by compensating it with energy stored in ESD. Continuous average value model of multilevel S-PWM has been presented also. Summary of raised problem is a simulation model made in PowerSim Psim 8...
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Depth Images Filtering In Distributed Streaming
PublicationIn this paper, we propose a distributed system for point cloud processing and transferring them via computer network regarding to effectiveness-related requirements. We discuss the comparison of point cloud filters focusing on their usage for streaming optimization. For the filtering step of the stream pipeline processing we evaluate four filters: Voxel Grid, Radial Outliner Remover, Statistical Outlier Removal and Pass Through....
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SELECTED COMBINED POWER SYSTEMS CONSISTED OF SELFIGNITION ENGINE AND STEAM TURBINE
PublicationThis paper presents optimization of selected combined diesel engine-steam turbine systems. Two systems: the system combined with waste heat one-pressure boiler only and its version containing additionally low-pressure boiler proper feeding degasifier and the system of two-pressure cycle, were taken into considerations. Their surplus values of power output and efficiency associated with utilization of waste heat contained in piston...
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Cost-Efficient Surrogate Modeling of High-Frequency Structures Using Nested Kriging with Automated Adjustment of Model Domain Lateral Dimensions
PublicationSurrogate models are becoming popular tools of choice in mitigating issues related to the excessive cost of electromagnetic (EM)-driven design of high-frequency structures. Among available techniques, approximation modeling is by far the most popular due to its versatility. In particular, the surrogates are exclusively based on the sampled simulation data with no need to involve engineering insight or problem-specific knowledge....
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How Integration of a Brain-Machine Interface and Obstacle Detection System Can Improve Wheelchair Control via Movement Image
PublicationThis study presents a human-computer interaction combined with a brain-machine interface (BMI) and obstacle detection system for remote control of a wheeled robot through movement imagery, providing a potential solution for individuals facing challenges with conventional vehicle operation. The primary focus of this work is the classification of surface EEG signals related to mental activity when envisioning movement and deep relaxation...
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Generalization of Kramers-Krönig relations for evaluation of causality in power-law media
PublicationClassical Kramers-Krönig (K–K) relations connect real and imaginary parts of the frequency-domain response of a system. The K–K relations also hold between the logarithm of modulus and the argument of the response, e.g. between the attenuation and the phase shift of a solution to a wave-propagation problem. For square-integrable functions of frequency, the satisfaction of classical K–K relations implies causality in the time domain....
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Quality Assurance of Educational Processes as the Foundation of the Quality Management System in Gdansk University of Technology
PublicationThe paper presents a model of quality management system (QMS) developed by the author in Gdansk University of Technology (GUT). The core of the model is internal quality assurance system of educational processes based on the ENQA guidelines. Next described in the paper steps of GUT QMS development are the implementation of one of the normative QMS models (e.g. ISO 9001, ISO/IEC 17025) in selected organizational units of GUT and...
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Analysis of electricity generation variability in 2019 with special consideration of electrical energy generation from wind sources.
PublicationThis article presents issues related to the broadly understood development of wind energy. The state of the art of wind energy in the world has been discussed. This paper also shows issues related to factors affecting the development of renewable energy sources and their impact on the natural environment on the basis of available research. The focus is, however, on the critical analysis of phenomena in the data of the Transmission...
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Adsorption of Cr(VI) in aqueous solution using sago bark (Metroxylon sagu) as a new potential biosorbent
PublicationThis paper investigated the ability of sago bark (Metroxylon sagu) as a new potential biosorbent in removing Cr(VI) in batch system. The optimum adsorption capacity of sago bark (Metroxylon sagu) was 61.73 mg/g achieved at pH 3, agitation rate of 100 rpm, contact time 60 min, particle size ≤32 μm, and initial concentration of Cr(VI) 1,000 mg/L at room temperature (25°C). The adsorbent regeneration was carried out using 0.01 M HNO3...
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50’ Sail Catamaran with Hybrid Propulsion, Design, Theoretical and Experimental Studies
PublicationThe development of modern lithium batteries and propulsion systems now allows the use of complex propulsion systems for vessels of various sizes. As part of the research and implementation project, a parallel hybrid drive system was designed, built and then tested in the laboratory. The experimental studies conducted allowed for the measurements of power, fuel consumption and electric power distribution in various operating modes...
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Multiple-Input Multiple-Output Technique for Underwater Acoustic Communication System
PublicationThe performance of an underwater acoustic communication (UAC) system is limited due to tough propagation conditions in the UAC channel. Multiple-Input Multiple-Output (MIMO) technique can improve the reliability of the data transmission system, increase its speed, increase its range, and reduce the energy consumption. The paper presents an implementation method of MIMO technique in the form of coding the Space-Time Block Code and...
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Activity coordination of capacitor banks and power transformer controllers in order to reduce power losses in the MV grid
PublicationOne of the main issues related to the optimization of the MV (middle voltage) network is to reduce losses of active and reactive power. Lower losses of active and reactive power give not only economic advantage, but also improvement of energy quality. The object of regulation that can be used for these purposes are transformer with On-Load Tap Changer and capacitor's banks. This paper presents results of analysis of the possibility...
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Explicit Size-Reduction of Circularly Polarized Antennas through Constrained Optimization with Penalty Factor Adjustment
PublicationModern communication systems of high data capacity incorporate circular polarization (CP) as the preferred antenna radiation field configuration. In many applications, integration of the system circuitry with antennas imposes size limitations on CP radiators, which makes their development process a challenging endeavor. This can be mitigated by means of simulation-driven design, specifically, constrained numerical optimization....
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Born–Oppenheimer potential energy curves of NaK from the optimised atomic basis sets
PublicationThe article presents adiabatic potential energy curves of the ground and excited electronic states for the diatomic NaK molecule. The calculations were made using the ab initio computational methods to include electron correlation. The studied molecule was calculated as the effective two-electron problem, in which only the valence electrons of the molecule are explicitly taken into account. The remaining electrons with atomic nuclei...
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Energy Loss Coefficients ki in a Displacement Pump and Hydraulic Motor used in Hydrostatic Drives
PublicationThe article aims at defining and analysing the energy loss coefficients in design solutions of rotating displacement machines, with a piston machine as an example. The energy losses observed in these machines include mechanical loss, volumetric loss, and pressure loss. The scale and relations between these losses in different machines depend on machine design and manufacturing quality, and on operating parameters. The operating...
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An Attempt to Create Speech Synthesis Model That Retains Lombard Effect Characteristics
PublicationThe speech with the Lombard effect has been extensively studied in the context of speech recognition or speech enhancement. However, few studies have investigated the Lombard effect in the context of speech synthesis. The aim of this paper is to create a mathematical model that allows for retaining the Lombard effect. These models could be used as a basis of a formant speech synthesizer. The proposed models are based on dividing...
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Inline Microwave Filters With N+1 Transmission Zeros Generated by Frequency-Variant Couplings: Coupling-Matrix-Based Synthesis and Design
PublicationA general coupling-matrix-based synthesis methodology for inline Nth-order microwave bandpass filters (BPFs) with frequency-variant reactive-type couplings that generate N+1 transmission zeros (TZs) is presented in this brief. The proposed approach exploits the formulation of the synthesis problem as three inverse nonlinear eigenvalue problems (INEVPs) so that the coupling matrix is built from their sets of eigenvalues. For this...
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Neural networks and deep learning
PublicationIn this chapter we will provide the general and fundamental background related to Neural Networks and Deep Learning techniques. Specifically, we divide the fundamentals of deep learning in three parts, the first one introduces Deep Feed Forward Networks and the main training algorithms in the context of optimization. The second part covers Convolutional Neural Networks (CNN) and discusses their main advantages and shortcomings...
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Global sensitivity analysis of membrane model of abdominal wall with surgical mesh
PublicationThe paper addresses the issue of ventral hernia repair. Finite Element simulations can be helpful in the optimization of hernia parameters. A membrane abdominal wall model is proposed in two variants: a healthy one and including hernia defect repaired by implant. The models include many uncertainties, e.g. due to variability of abdominal wall, intraabdominal pressure value etc. Measuring mechanical properties with high accuracy...
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Regression points in non-intrusive polynomial chaos expansion method and D-optimal design
PublicationThe paper addresses selected issues of uncertainty quantification in the modelling of a system containing surgical mesh used in ventral hernia repair. Uncertainties in the models occur e.g. due to variability of abdominal wall properties among others. In order to include them, a non-intrusive regression-based polynomial chaos expansion method is employed. Its accuracy depends on the choice of regression points. In the study a relation...
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Mathematical Models of Control Systems of Angular Speed of Steam Turbines for Diagnostic Tests of Automatic and Mechatronic Devices
PublicationAccurate modeling of physical processes of many automatics and mechatronics systems is often necessity. In power system such a process is control of angular velocity of power objects during connection to operation in parallel. This process is extremely dynamic. For this reason response of control system depends from changes of many physical parameters (temperature, pressure and flow of the medium, etc.). Precision modeling influences...
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Energy losses in hydrostatic drive:Drive investigation method compatible with diagram of power increase opposite to the direction of power flow
PublicationEnergy losses and efficiency of drive motor must be presented as functions of physical quantities independent of losses in the motor. Such quantities are speed and load required by the driven device, changing in the drive operating field. Speed and load decide of the useful power and, in differentiated way, of kinds and values of losses in the motor. But energy losses and efficiency of drive motors are evaluated as functions of...