Search
displaying 1000 best results Help
Search results for: ADJUSTABLE-SPEED DRIVES
-
A modified method of vibration surveillance by using the optimal control at energy performance index
PublicationA method of vibration surveillance by using the optimal control at energy performance index has been creatively modified. The suggested original modification depends on consideration of direct relationship between the measured acceleration signal and the optimal control command. The paper presents the results of experiments and Hardware- in-the-loop simulations of a new active vibration reduction algorithm based on the energy...
-
Properties of surface layers of titanium alloy Ti6Al4V after laser melting processes
PublicationThe article presents the investigation results of titanium alloy Ti6Al4V surface layer after laser melting process. The process of laser melting was performed using Nd-YAG laser. The evaluation of structure of the alloy as well as hardness and chemical composition was performed. It was shown that laser melting changes the structure and properties of titanium alloy Ti6Al4V and process parameters as scanning speed affects the thickness...
-
Solving the Problem of Dynamic Adaptability of Artificial Intelligence Systems that Control Dynamic Technical Objects
PublicationThis paper investigates the increase in the response speed and stability of artificial intelligence systems that control dynamic technical objects. The problem of calculating the optimal time of switching an artificial intelligence system between software classes by the criterion of the rigidity degree of the model of a control object is considered. The solution of this problem is proposed for the general case of the control object...
-
Chosen Analysis Results Of The Prototype Multicell Piezoelectric Motor
PublicationThis paper presents the design, modeling and tests of the prototype multicell piezoelectric motor (MPM). A new concept of the electromechanical structure of the considered prototype is based on three rotating-mode actuators. The electromechanical structure of each actuator has been considered as an independent one - referred to as a “single cell” (single actuator). Combined three resonant actuators generate three traveling waves...
-
Ab-initio study of electrical and optical properties of allylamine
PublicationThe Density functional theory is one of most promising methodology in fast and accurate calculations of electrical and optical properties from the atomic basis. In this paper, we calculate electrical and optical properties of allylamine (2-propen 1- amine) in terms of accuracy and speed of calculations obtained by selection of DFT-1/2 method with ultrasoft Vanderbilt pseudopotentials. Comparison of density of states between molecule...
-
New concept and analysis of the multicell piezoelectric motor
PublicationThis work presents the design, modeling and tests of the prototype multicell piezoelectric motor (MPM). A new concept of the electromechanical structure of the considered prototype is based on three rotating-mode actuators. The electromechanical structure of each actuator has been considered as an independent one - referred to as a ”single cell” (single actuator). Combined three resonant actuators generate three traveling waves...
-
Sensorless Disturbance Detection for Five Phase Induction Motor with Third Harmonic Injection
PublicationThe paper presents a sensorless disturbance detection procedure that was done on a five phase induction motor with third harmonic injection. A test bench was developed where a three phase machine serves as disturbance generator of different frequencies. The control of the machines is based on multi scalar variables that ensures an independent control of the motor EMF and the rotor flux. For disturbance identification a speed observer...
-
Evolutionary Ship Track Planning within Traffic Separation Schemes – Evaluation of Individuals
PublicationThe paper presents an extended version of the author’s Evolutionary Sets of Safe Ship Trajectories method. The method plans safe tracks of all ships involved in an encounter including speed reduction manoeuvres, if necessary, and taking into account Rule 10 of COLREGS, which specifies ships’ behaviour within Traffic Separation Schemes governed by IMO. The paper focuses on the evaluation phase of the evolutionary process and shows...
-
Estimation of interior-permanent-magnet-synchronous-motor rotor position by analysis of phase-current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM rotor angular position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Calculation of the motor position is performed in every PWM cycle. The standard SV-PWM method is used to determine...
-
Vibration of the bridge under moving singular loads - theoretical formulation and numerical solution
PublicationThe paper presents the results of the numerical analysis of a simple vehicle passing over a simply supported bridge span. The bridge is modelled by a Euler-Bernoulli beam. The vehicle is modelled as a linear, visco-elastic oscillator, moving at a constant speed. The system is described by a set of differential equations of motion and solved numerically using the Runge-Kutta algorithm. The results are compared with the solution...
-
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...
-
Tool Wear Prediction in Single-Sided Lapping Process
PublicationSingle-sided lapping is one of the most effective planarization technologies. The process has relatively complex kinematics and it is determined by a number of inputs parameters. It has been noted that prediction of the tool wear during the process is critical for product quality control. To determine the profile wear of the lapping plate, a computer model which simulates abrasive grains trajectories was developed in MATLAB. Moreover,...
-
Audible noise in ship’s electrical drive systems with frequency converters
Open Research DataThe presented dataset is part of research focusing on the impact of the ship's electrical drive systems with frequency converters on vibrations and the level of audible noise on ships.
-
Wpływ zmian dopuszczalnych wartości parametrów geometrycznych i kinematycznych na podatność modernizacyjną układów torowych
PublicationPodatnością modernizacyjną nazywamy stopień przystosowania analizowanego odcinka linii kolejowej do zmiany prędkości eksploatacyjnej. Skala możliwych zmian prędkości (w sensie jej zwiększenia) jest wypadkową istniejącego układu geometrycznego linii w planie, ograniczeń lokalizacyjnych oraz dopuszczalnych wartości parametrów geometrycznych i kinematycznych. Jakiekolwiek zmiany tych ostatnich wpływają bezpośrednio na obliczenie elementarnych...
-
Apparent molar volumes and compressibilities of alkaline earth metal ions in methanol and dimethylsulfoxide
PublicationTemperature dependencies of density of magnesium (II), calcium (II), strontium (II), barium (II) perchlorates as well as beryllium (II), and sodium trifluoromethanesulfonates in methanol and dimethylsulfoxide have been determined over the composition range studied. From density data the apparent molar volumes and partial molar volumes of the salts at infinite dilution as well as the expansibilities have been evaluated. The apparent...
-
Disturbances of magnetic field in surrounding of mobile, metalic plate
PublicationThe uniform magnetic field of the Earth in the surrounding of a mobile, metalic object undergoes deformation by eddy currents. The influence of the moving conducting object on total magnetic field of the Earth depends on the object's shape, position and speed of the changes relative to the magnetic field's vector of the Earth as well as the electric conductivity and the relative magnetic permeability of the material. The disturbances...
-
The Imaging of Gdansk Bay Seabed by Using Side Sonar
PublicationThis paper is mainly aimed at presentation of an impact of environmental conditions on imaging accuracy by using hydro-acoustic systems in waters of a high non-uniformity of spatial distribution of hydrological parameters. Impact of refraction on erroneous estimation of range, in case of wave radiation into water under a large angle, like in side sonars or multi-beam echo-sounders, is especially important. In this paper seasonal...
-
The study of acoustic climate of the Southern Baltic
PublicationThis paper presents the statistical characteristics of seawater properties, which are necessary for predicting the propagation of acoustic waves in selected areas of the Baltic Sea. The statistics were elaborated based on long-term measurements of vertical distributions of sound speed, temperature, and salinity, and the nonlinearity parameter B/A. Nonlinear properties of the environment are considered, in connection...
-
Effect of underwater local cavity welding method conditions on diffusible hydrogen content in deposited metal
PublicationOne of the methods with great potential for applications in underwater repairs is local cavity welding. In local cavity method, cooling conditions and diffusible hydrogen amount in weld metal are nearly the same as those existed during welding in the air. This paper presents the results of literature survey and preliminary tests of the effect of local cavity welding conditions on diffusible hydrogen amount in a deposited metal....
-
IPMSM rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM angular rotor position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Algorithm is characterised by a very simple formulae. The calculation of rotor position is performed in every PWM...
-
Simple gait parameterization and 3D animation for anonymous visual monitoring based on augmented reality
PublicationThe article presents a method for video anonymization and replacing real human silhouettes with virtual 3D figures rendered on a screen. Video stream is processed to detect and to track objects, whereas anonymization stage employs animating avatars accordingly to behavior of detected persons. Location, movement speed, direction, and person height are taken into account during animation and rendering phases. This approach requires...
-
Design and modeling of the piezoelectric motor based on three resonance actuators
PublicationThis paper describes a piezoelectric motor which combines advantages from two existing piezoelectric motors topologies. The research work presents the design, simulations and measurements of the piezoelectric motor with three rotation-mode actuators. The aim of the project was to obtain the high speed piezoelectric motor. Other advantages of this conception are blocking torque, short response times, the ability to work in a hostile...
-
Comparison of natural frequencies of a circular saw blade obtained empirically and with FEM
PublicationThe knowledge of the natural frequencies’ values of circular saw blades is necessary to determine the minimal critical rotational speed in which they can work with required stability. Moreover, testing the circular saw blades with more complicated shapes, e.g. which have additional holes inside blades for cleaning knifes or additional indirect teeth in gullets, reveals some kind of problematic properties of these saw blades. The...
-
Evaluation of Wear Resistance of Ti alloys used for elements friction of knee endoprosthesis
PublicationThe paper presents research results of resistance to abrasive wear of titanium alloys: Ti6Al4V (commonly used) and Til3Nb13Zr (alloy of new generation) in association with polyethylene (UHMW-PE) predisposed for elements on pair of the knee endoprosthesis. The results were analysed from the point of possibility of an use of new generation titanium alloys as components of such implants. The tests of resistance to abrasive wear of...
-
Investigations on mixture preparation for two phase adiabatic pressure drop of R134a flowing in 5 mm diameter channel
PublicationThe article presents detailed two-phase adiabatic pressure drops data for refrigerant R134a. Study cases have been set for a mass flux varying from 200 to 400 kg/m2 s, at the saturation temperature of 19.4 ◦C. Obtained experimental data was compared with the available correlations from the literature for the frictional pressure drop during adiabatic flow. Influence of mixture preparation on pressure drop was investigated, for...
-
Modelling of the Movement of Designed Vehicles on Parking Space for Designing Parking
PublicationNowadays, in all cities there is an acute problem of lack of parking spaces. The vehicles are becoming more and more not only in megacities, but also in small cities of the country, and there are no more parking places - the pace of solving the problem is several times slower than the speed of transport growth among the citizens. The article is dedicated to determination of the optimum sizes parking place for designing vehicles...
-
Mathematical Models in Design Process of Ship Bow Thrusters
PublicationThe paper describes an application of simulation models for computer-aided design of ship bow thrusters. Generation of simulation models of ship bow thruster requires development and verifying of mathematical models of system component elements. Using the results of simulation the expert system is able to determine, that the rules of classification societies are met. Design procedures and mathematical models are part of an expert...
-
Mathematical Models in Design Process of Ship Bow Thrusters
PublicationThe presentation is about an application of simulation models for computer-aided design of ship bow thrusters. Generation of simulation models of ship bow thruster requires development and verifying of mathematical models of system component elements. Using the results of simulation the expert system is able to determine, that the rules of classification societies are met. Design procedures and mathematical models are part of an...
-
Fluctuation-Enhanced Sensing (FES): A Promising Sensing Technique
PublicationFluctuation-enhanced sensing (FES) is a very powerful odor and gas sensing technique and as such it can play a fundamental role in the control of environments and, therefore, in the protection of health. For this reason, we conduct a comprehensive survey on the state-of-the-art of the FES technique, highlighting potentials and limits. Particular attention is paid to the dedicated instrumentation necessary for the application of...
-
Simplified Map-based Selection of Optimal Spindle Speeds When Milling Complex Structures
PublicationIn the paper a method for selecting optimal spindle speeds for complex structures during milling operations is presented. It is based on the selection of the spindle speed in accordance with a simple equation resulting from the minimisation of vibration energy, which leads to the minimisation of the work of cut-ting forces presented in previous elaborations by the authors [1]. Optimal spindle speeds are obtained for many points...
-
Robert Dobieglewski
People -
Effect of underwater friction stir welding parameters on AA5754 alloy joints: experimental studies
PublicationThe water as a welding environment may generate serious technological and metallurgical problems but in certain cases, the physicochemical properties of water can be used effectively, e.g., to impart the specific properties of welded materials. The purpose of the work was verification of effectiveness of the water cooling of aluminium alloy AA5754 for various sets of technological parameters of underwater friction stir welding...
-
Investigation of Weigh-in-Motion Measurement Accuracy on the Basis of Steering Axle Load Spectra
PublicationWeigh-in-motion systems are installed in pavements or on bridges to identify and reduce the number of overloaded vehicles and minimise their adverse eect on road infrastructure. Moreover, the collected trac data are used to obtain axle load characteristics, which are very useful in road infrastructure design. Practical application of data from weigh-in-motion has become more common recently, which calls for adequate attention to...
-
Effect of Processing Parameters on Strength and Corrosion Resistance of Friction Stir-Welded AA6082
PublicationThe friction stir welding method is increasingly attracting interest in the railway sector due to its environmental friendliness, low cost, and ease of producing high-quality joints. Using aluminum alloys reduces the weight of structures, increasing their payload and reducing fuel consumption and running costs. The following paper presents studies on the microstructure, strength, and corrosion resistance of AA6082 aluminum alloy...
-
Research of Emergency Modes of Wind Power Plants Using Computer Simulation
PublicationThe aim of this study is to investigate changes in the wind power plant energy production parameters under the conditions of sudden wind changes and voltage drop. To achieve these goals, a simulation of operation of wind power plants was performed. Twelve wind turbines with variable rotational speed equipped with a Fuhrländer FL 2500/104 asynchronous double-fed induction generator (DFIG) were used, each with an installed capacity...
-
Analysis of Residual Stresses and Dislocation Density of AA6082 Butt Welds Produced by Friction Sir Welding
PublicationThe Friction Stir Welding (FSW) method was employed to join AA6082 sheets. The welds were produced with different tool traverse speed (200 and 250 mm/min), rotational speed (1000 and 1250 RPM) and tool tilt angle (0 and 2 deg). Based on the analysis of XRD patterns, the total precipitation volume fractions in the nugget zones and the base material were calculated. The FSW process resulted in a reduction in the fraction of precipitates...
-
Energy Management for PV Powered Hybrid Storage System in Electric Vehicles Using Artificial Neural Network and Aquila Optimizer Algorithm
PublicationIn an electric vehicle (EV), using more than one energy source often provides a safe ride without concerns about range. EVs are powered by photovoltaic (PV), battery, and ultracapacitor (UC) systems. The overall results of this arrangement are an increase in travel distance; a reduction in battery size; improved reaction, especially under overload; and an extension of battery life. Improved results allow the energy to be used efficiently,...
-
Contribution of dynamic vehicle loads to pavement failure
PublicationPavement surfaces are not ideally even, which causes dynamic loads of vehicle axles. Distribution of dynamic loads of a given axle is similar to normal distribution and can be described by static load and dynamic load coefficient. The dynamic load coefficient depends on road profile, vehicle speed, properties of suspensions and static load of axle. While for a given road section road profile remains constant, vehicle speed and...
-
Współczynniki strat energetycznych w elementach napędu hydrostatycznego
PublicationW każdym układzie napędowym należy zastąpić obraz przepływu mocy opisany dotychczas powszechnie stosowanym wykresem Sankey’a spadku mocy zgodnego z kierunkiem przepływu mocy proponowanym przez autora wykresem wzrostu mocy w układzie przeciwnego do kierunku przepływu mocy. Należy więc opisywać straty i sprawność energetyczną a także pole pracy każdego silnika i układu napędowego jako zależne od wielkości fizycznych niezależnych...
-
Direct determination of paraquat herbicide by square-wave voltammetry by two-step transfer mechanism at heterogeneous boron-doped carbon nanowall electrodes
PublicationBoron-doped carbon nanowalls (B:CNW) versus boron-doped diamond (BDD) materials were investigated for the effective electrochemical detection of highly toxic herbicide paraquat (PQ). Depending on the surface morphology and functional groups of BDD and B:CNWs, the electrochemical absorption and detection of the target analyte PQ revealed different detection mechanisms. The surface absorption mechanism was mainly observed for BDD,...
-
Tensile strength test of PE foils modified with zinc oxide and zinc salts
Open Research DataThis dataset contains the results of PE foils mechanical tests, in which the material was evaluated for strength and extensibility at the moment of breaking and based on the same tests preceded by material fatigue in 50 stretching cycles. The principle of the method is to stretch the test sample placed in the clamps of the stretching apparatus at a...
-
One Europe, one product, two prices - the price disparity in the EU
PublicationThe price dispersion in the European Union in the last fifteen years (1990-2005) is analysed. The analysis of price convergence is examined on aggregate and disaggregate levels. The macro approach is based on Comparative Price Level index calculated as the ratio between PPPs and exchange rate. The disaggregate analysis utilizesactual prices of 148 individual products sold in the 15 capital cities of the EU. The calculations comprise...
-
Characteristics of an image sensor with early-vision processing fabricated in standard 0.35 µm CMOS technology
PublicationThe article presents measurement results of prototype integrated circuits for acquisition and processing of images in real time. In order to verify a new concept of circuit solutions of analogue image processors, experimental integrated circuits were fabricated. The integrated circuits, designed in a standard 0.35 µm CMOS technology, contain the image sensor and analogue processors that perform low-level convolution-based image...
-
Application of wireless communication to small WECS with induction generator
PublicationWind energy conversion systems (WECS) seem to be self-evident elements of the future smart grids. Among many generator types the squirrel cage induction generator (SCIG) characterizes robustness and low cost. A full-scale power converter can perform smooth grid connection over wide speed range of multiple-stage geared SCIG. Increasing number of sensors can improve the WECS control and diagnostics but increasing number of thin wires...
-
Analog CMOS processor for early vision processing with highly reduced power consumption
PublicationA new approach to an analog ultra-low power visionchip design is presented. The prototype chip performs low-levelconvolutional image processing algorithms in real time. Thecircuit is implemented in 0.35 μm CMOS technology, contains64 x 64 SIMD matrix with embedded analogue processors APE(Analogue Processing Element). The photo-sensitive-matrix is of2.2 μm x 2.2 μm size, giving the density of 877 processors permm2. The matrix dissipates...
-
Comparison of Tracking Methods in Respect of Automation of Animal Behavioral Test
PublicationAutomation in experiments carried out on animals is getting more and more important in research. Computers take over laborious and time-consuming activities like recording and analysing images of experiment scene. The first step in an image analysis is finding and distinguishing between the observed animals, and then tracking all objects during the experiment. In this paper four tracking methods are presented. Quantitative and...
-
Numerical investigation on the performance of a small counter-rotating wind turbine
PublicationThe article presents the results of the investigation on the performance of a small counter-rotating wind turbine. The wind turbine has been simulated using Computational Fluid Dynamics methods. Actuator Line Model has been successfully used to represent rotors in the computational domain. A parametric study has been carried out, taking into account changes in the tip speed ratio of the rotors while maintaining a constant distance...
-
Emotion Recognition - the need for a complete analysis of the phenomenon of expression formation
PublicationThis article shows how complex emotions are. This has been proven by the analysis of the changes that occur on the face. The authors present the problem of image analysis for the purpose of identifying emotions. In addition, they point out the importance of recording the phenomenon of the development of emotions on the human face with the use of high-speed cameras, which allows the detection of micro expression. The work that was...
-
TIRE/ROAD NOISE AND TIRE ROLLING RESISTANCE ON PROTOTYPE PERS SURFACE
PublicationPoroelastic road surfaces are characterized by low noise of tires running on them.Road pavements of this type are promising solution to problems related to traffic noise in cities and on rural roads. Some technical problems still have to be solved, in particular regarding durability and skid resistance on wet surface. Ongoing and planned works are to contribute to create a quiet, durable and safe road surface, which will become...
-
Application in circular sawing machines of the experimental results of investigations of the chip removing system operation
PublicationThe experimental results of the chip removing system operation are presented. The main aim of them was to optimize suction system of the panel saw Fx3 and its follower Fx550. The attention was focused on the upper casing, which was the part of removing system. Within the framework of the work a systematic experimental study of pressure distribution in the casing during operation of the selected rotational speed of saw blade with...