Filters
total: 1509
filtered: 1206
displaying 1000 best results Help
Search results for: INTERNAL CHANNELS IN MOTOR
-
Analysis of the possibilities of using of DME fuel in motor boat drive systems
PublicationThe characteristics of alternative fuel for diesel: dimethyl ether (DME) and an analysis of the potential to reduce emissions of toxic compounds by the engines when running on this fuel have been presented in this work. Basic types of design solutions of gas supply and control systems, possible for use in internal combustion engines with DME supply have been also presented. The paper presents a study of the legislation and an analysis...
-
Fading modelling in dynamic off-body channels
Publication -
One-Dimensional Modeling of Flows in Open Channels
PublicationIn this chapter, modeling of the unsteady open channel flow using one-dimensional approach is considered. As this question belongs to the well-known and standard problems of open channel hydraulic engineering, comprehensively presented and described in many books and publications, our attention is focused on some selected aspects only. As far as the numerical solution of the governing equations is considered, one can find out that...
-
Nonadditivity of quantum capacity for multiparty communication channels.
PublicationZbadano scenariusze komunikacji pomiędzy wieloma stronami gdzie informacje są przesyłane od wielu nadawców do wielu odbiorców.
-
Fading Modelling in Dynamic Off-Body Channels
PublicationThis paper presents an off-body fading channel model for Body Area Networks. The proposed model, based on both simulations and measurements at 2.45 GHz in a realistic indoor environment, consists of three components: mean path loss, body shadowing, and multipath fading. The first is modelled as a log function of distance, the path loss exponent being in between 0.4 and 1.6. A statistical perspective is taken for the other two components,...
-
Fading Modelling in Dynamic Off-Body Channels
PublicationThis paper presents an off-body fading channel model for Body Area Networks (BANs) in indoor environments. The proposed model, which is based on both simulations and measurements in a realistic environment, consists of three components: mean path loss, body shadowing, and multipath fading. Seven scenarios in an indoor environment (a medium-size room with furniture, mostly consisting of wooden tables and chairs) have been measured:...
-
Modeling the impact of rotor movement on non-linearity of motor currents waveforms in high-speed PMSM drives
PublicationMotor current measurement techniques as well as predictive control algorithms for electric drives rely on an assumption of linear motor currents changes resulting from constant inverter output voltages. Recent research has reported that this assumption does not hold in motors with short electrical time constant, and in drives whose rotor position advances substantially during a control period. This paper proposes a simulation model...
-
Assessing Acute Toxicity of Selected Packages Internal Layers Extracts using Microtox®
PublicationIn the scientific literature related to the widely understood issue of packaging materials designed to have contact with food (food contact materials), there is much information on raw materials used for their production, as well as their physiochemical properties, types and parameters. Unfortunately, not much attention is given to the issues concerning migration of toxic substances from packaging and its actual influence on the...
-
High Frequency Conducted Emission in AC Motor Drives Fed By Frequency Converters: Sources and Propagation Paths
PublicationProvides a concise and thorough reference for designing electrical and electronic systems that employ adjustable speed drives Electrical and electronic systems that employ adjustable speed drives are being increasingly used in present-day automation applications. They are considered by many application engineers as one of the most interfering components, especially in a contemporarily faced industrial environment. This book fills...
-
Core loss resistance impact on sensorless speed control of an induction motor using hybrid adaptive sliding mode observer
PublicationInduction motors (IMs) experience power losses when a portion of the input power is converted to heat instead of driving the load. The combined effect of copper losses, core losses, and mechanical losses results in IM power losses. Unfortunately, the core losses in the motor, which have a considerable impact on its energy efficiency, are not taken into account by the generally employed dynamic model in the majority of the studies. Due...
-
Internal friction in FePd alloy during ordering
PublicationStwierdzono występowanie wysokiego poziomu tarcia wewnętrznego w zahartowanym stopie FePd (50% at. Pd). Zbadano proces uporządkowania atomowego w korelacji ze zmianami tarcia wewnętrznego defektu modułu i relaksacji magnetycznej stopu porządkującego się podczas nagrzewania do 900 K. Zaobserwowano efekt prędkości nagrzewania na punkt Curie.
-
3D Hand Shape Modeling for Automatic Assessing Motor Performance in Parkinson's Disease
PublicationIn this paper a method for hand pattern processing to create a 3D hand model is presented. By applying a complete hand armature to the model obtained, an interpolation of three motor tests for an individual Parkinson's disease patient can be performed. To obtain the 3D hand model the top view of the hand from a web cam is analyzed. The hand contour is examined to find characteristic points that allows for dividing hand image into...
-
Energy losses in the hydraulic rotational motor - definitions and relations for evaluation of the efficiency of motor and hydrostatic drive
PublicationStosowane dotychczas w badaniach naukowych i w praktyce przemysłowej metody oceny strat i sprawności energetycznej obrotowych silników hydraulicznych stosowanych w napędach hydrostatycznych dają błędne rezultaty, ponieważ obarczone są wpływem samych strat na parametry, w funkcji których straty i sprawności są oceniane.Celem pracy było zdefiniowanie w silniku parametrów pracy, rozwijanych mocy, występujących strat i sprawności energetycznej...
-
Capturing nonexponential dynamics in the presence of two decay channels
Publication -
Ultrawideband transmission in physical channels: a broadband interference view
PublicationThe superposition of multipath components (MPC) of an emitted wave, formed by reflections from limiting surfaces and obstacles in the propagation area, strongly affects communication signals. In the case of modern wideband systems, the effect should be seen as a broadband counterpart of classical interference which is the cause of fading in narrowband systems. This paper shows that in wideband communications, the time- and frequency-domain...
-
Experimental investigations on condensation in flow in small diameter channels
PublicationW pracy przedstawiono innowacyjne podejście do eksperymentalnych badań kondensacji w przepływie oraz omówiono wstępne wyniki badań eksperymentalnych kondensacji etanolu w pionowej rurce srebrnej o średnicy wewnętrznej 2.3 mm.
-
Perceptual and Motor Effects of Muscle Co-activation in a Force Production Task
PublicationWe tested several predictions of the theory of motor control with spatial referent coordinates related to effects of muscle coactivation on force production and perception. In particular, we predicted that subjects would produce unintentional force increase by finger flexors and be unaware of this force increase. Healthy subjects performed steady force production task in isometric conditions with visual feedback on the force level....
-
Derivation of motor mean phase currents in PMSM drives operating with low switching-to-fundamental frequency ratio
PublicationPulse width modulation (PWM) of inverter output voltage causes the waveforms of motor phase cur-rents to consist of distinctive ripples. In order to provide suitable feedback for the motor current con-trollers, the mean value must be extracted from the currents’ waveforms in every PWM cycle. A com-mon solution to derive the mean phase currents is to sample their value at the midpoint of a symmetrical PWM cycle. Using an assumption...
-
Weather Hazard Avoidance in Modeling Safety of Motor-Driven Ship for Multicriteria Weather Routing
PublicationWeather routing methods find the most suitable ocean?s route for a vessel, taking into account changeable weather conditions and navigational constraints. In the multicriteria approach based on the evolutionary SPEA algorithm one is able to consider a few constrained criteria simultaneously. The approach applied for a ship with hybrid propulsions has already been presented by one of the authors on previous TransNav?2009. This time...
-
Sensorless five-phase induction motor drive with third harmonic injection and inverter output filter
PublicationThe paper presents a sensorless control approach for a five-phase induction motor drive with third harmonic injection and inverter output filter. In the case of the third harmonic injection being utilised in the control, the physical machine has to be divided into two virtual machines that are controlled separately and independently. The control system structure is presented in conjunction with speed and rotor flux observers that...
-
Switching Regulation in the Control of 5-Phase Permanent Magnet Synchronous Motor Fed by 3×5 Direct Matrix Converter
PublicationMatrix converter is an AC-AC direct power converter comprising of an array of bi- directional switches. It does not require an intermediate DC-link and allows sinusoidal output waveforms with varying amplitudes and frequencies. The configuration of these bi- directional switches decides the number of inputs and outputs...
-
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...
-
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...
-
The impact of internal and international migration on regional convergence in Poland
PublicationAccording to neoclassical theory, migration is expected to speed up the convergence process between countries (Barro, Sala-i-Martin 2004). The flow of labour from low-wage regions to high-wage regions should equalise payrolls. However, the impact of migration on convergence rates is unclear when the labour flow is heterogeneous. Moreover, the movement of labour towards wealthier areas depresses the demand for goods, services and...
-
ANALYSIS OF INTERNAL SOURCES OF HAZARDS IN CIVIL AIR OPERATIONS
Publication -
Influence of geometrical and operational parameters on tooth wear in the working mechanism of a satellite motor
PublicationThis article describes the phenomena affecting the wear of the rotor of the working mechanism in a hydraulic satellite motor. The basic geometrical relationships that allow the calculation of the coordinates of the points of contact between the satellite and the rotor and the curvature are presented. A method for calculating the number of contacts of the satellite teeth with the rotor teeth and of the satellite teeth with the curvature...
-
Control of five-phase induction motor
Publication -
The influence of the motor filtrers on harmonic current emmision in the pro-ective connection of drive systems.
PublicationThis paper contains detailed analysis of currents in protective wire in engine supplied from frequency converter without any external filters added. It was found that the peak value of current in protective conductor of engine was about 1500 mA at frequencies 5 Hz 50 Hz. In the continuation of research the dU/dt type motor filter and the sinusoidal filter were tested. It was found that the current in protective wire decreased...
-
MRAS-Based Switching Linear Feedback Strategy for Sensorless Speed Control of Induction Motor Drives
PublicationThis paper presents a newly designed switching linear feedback structure of sliding mode control (SLF-SMC) plugged with an model reference adaptive system (MRAS) based sensorless fieldoriented control (SFOC) for induction motor (IM). Indeed, the performance of the MRAS depends mainly on the operating point and the parametric variation of the IM. Hence, the sliding mode control (SMC) could be considered a good control alternative...
-
Properties of water in the region between a tubulin dimer and a single motor head of kinesin
PublicationA kinesin is a molecular motor that can perform movement on a microtubule track in a stepping-like manner. This motion is connected with processes of association and dissociation of kinesin and tubulin. Water is an important participant in these kinds of molecular interactions. This is why we have decided to investigate the dynamical and structural properties of water in the region between the kinesin catalytic domain and the tubulin...
-
Supply current signal and artificial neural networks in the induction motor bearings diagnostics
PublicationThis paper contains research results of the diagnostics of induction motor bearings based on measurement of the supply current with usage of artificial neural networks. Bearing failure amount is greater than 40% of all engine failures, which makes their damage-free operation crucial. Tests were performed on motors with intentionally made bearings defects. Chapter 2 introduces the concept of artificial neural networks. It presents...
-
A Comparative Study of Fuzzy SMC with Adaptive Fuzzy PID for Sensorless Speed Control of Six-Phase Induction Motor
PublicationMulti-phase motors have recently replaced three-phase induction motors in a variety of applications due to the numerous benefits they provide, and the absence of speed sensors promotes induction motors with variable speed drives. Sensorless speed control minimizes unnecessary speed encoder cost, reduces maintenance, and improves the motor drive’s reliability. The performance comparison of the fuzzy sliding mode controller (FSMC)...
-
A Comparative Study of Fuzzy SMC with Adaptive Fuzzy PID for Sensorless Speed Control of Six-Phase Induction Motor
PublicationMulti-phase motors have recently replaced three-phase induction motors in a variety of applications due to the numerous benefits they provide, and the absence of speed sensors promotes induction motors with variable speed drives. Sensorless speed control minimizes unnecessary speed encoder cost, reduces maintenance, and improves the motor drive’s reliability. The performance comparison of the fuzzy sliding mode controller (FSMC)...
-
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...
-
Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming
PublicationIn order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming (ADP) technique based on the internal model principle (IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback, merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization...
-
Shading of River Channels as an Important Factor Reducing Macrophyte Biodiversity
Publication -
Software tools for identification, visualization and analysis of protein tunnels and channels
Publication -
Computer-assisted enzyme engineering by modification of tunnels, channels and gates
Publication -
Measurements of Path Loss in Off-Body Channels in Indoor Environments
PublicationThe main goal of the paper is to investigate the influence of body orientation and on-body antenna placement on the path loss in off-body communications. In addition, the influence of different bodies is analysed.
-
On entaglement distillation and quantum error correction of unknown states and channels.
PublicationBadano niezmienniczości splątania kwantowego oraz pojemności kwantowego kanału ze względu na ewentualną utratę informacji o pojedynczej kopii kwantowego stanu. Pokazano, że jeżeli dany kwantowy kanał ma pewne pojemności niezerowe, to odpowiadające mu stany posiadają niezerowe destylowalne splątanie. Postawiono pewne otwarte problemy dotyczące destylowalności splątania.
-
Infrared techniques for natural convection investigations in channels between two vertical, parallel, isothermal and symmetrically heated plates
PublicationThe effect of the gap width between two symmetrically heated vertical, parallel, isothermal plates on intensity of natural convective heat transfer in a gas (Pr = 0.71) was experimentally studied using the balance and gradient methods. In the former method heat fluxes were determined based on measurements of the voltage and electric current supplying the heaters placed inside the walls. In the latter, heat fluxes were calculated...
-
Morphology and internal structure of small-scale washovers formed in the coastal zone of the semi-enclosed tideless basin, Gulf of Gdańsk, Baltic Sea
PublicationThis study explores the morphological features and internal structure of small-scale washovers along the southeastern Baltic Sea coast, providing insights into these most widespread yet often neglected deposits in the recent research of geomorphological and sedimentary record of storm surges. A 15-year-long record of morphological changes of the coast was acquired from regional orthophotos to analyse their geometry and spatial...
-
Sensorless Control of Induction Motor Based on Super-Twisting Sliding Mode Observer With Speed Convergence Improvement
PublicationThe super twisting sliding-mode observer (ST-SMO) has been proposed to achieve an effective method for alleviating low-order harmonics of measured quantities, issues related to DC drift, and suppression of chattering due to low-frequency sampling. The conventional ST-SMO, on the other hand, suffers from control delay in the convergence trajectory due to the system disturbance, resulting in decreased anti-disturbance capability...
-
Model-Free Controller Tuning Based on DFT Processing: Application to Induction Motor Drives
PublicationIn this paper, we present a new approach based on discrete Fourier transform (DFT) analysis for controller tuning of the closed-loop system with unknown plant. The DFT analysis is used to process the closed-loop measurements collected online to derive the frequency response of an initial closed-loop system that does not provide a good performance. Based on the closed-loop frequency response data, we propose two methods for tuning PID...
-
On the lack of explicit internal criticism of contemporary personalists. An outline of the problem
Publication -
Optimization of the geometry of the crankshaft for an internal combustion engine with heat regeneration
Publication -
Role of Dean’s Offices in Developing Internal Normative Acts at HEIs
Publication -
TEST FOR ASSESSING THE ENERGY EFFICIENCY OF VEHICLES WITH INTERNAL COMBUSTION ENGINES
PublicationThe most popular method for assessing the energy efficiency of vehicles is to compare the fuel consumption achieved in the conditions of selected approval test. Operating conditions are defined using the speed profiles, usually for only two categories: urban and extra-urban driving. Assessing the energy efficiency of vehicles should be performed using a more detailed classification of conditions. Presented results of comparison...
-
Construction of glucosamine-6-phosphate synthase with an internal hexahistydyl fragment
PublicationL-Glutamine: D-fructose-6-phosphate aminotransferase (EC 2.6.1.16), known also as glucosamine-6-phosphate (GlcN-6-P) syntase, catalyzes the first committed step in the amino sugar biosynthetic pathway in prokaryotic and eukaryotic organisms. The enzyme carries out a complex reaction involving ammonia transfer and sugar phosphate isomerization. GlcN-6-P syntase is an important point of metabolic control of amino sugar biosynthesis...
-
Internal friction in pure Co and CoPt alloy during ordering
PublicationZbadano tarcie wewnętrzne, wskaźnik modułu sprężystości postaciowej i podatność magnetyczną stopu CoPt (50% at. Pt) w stanie nieuporządkowanym, uzyskanym w wyniku oziębienia, podczas wyżarzania do 850 K przy wzrostach temperatury 6K/min. i 2K/min., stosując odwróconą skręcarkę wahadłową. Zaobserwowano maksimum tarcia wewnętrznego w CoPt przy 700 K oraz w monokrysztale kobaltu w 720 K w pobliżu martenzytycznej przemiany fazowej,...