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Wyniki wyszukiwania dla: A COMPUTER MODEL
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Bounds on the cover time of parallel rotor walks
PublikacjaThe rotor-router mechanism was introduced as a deterministic alternative to the random walk in undirected graphs. In this model, a set of k identical walkers is deployed in parallel, starting from a chosen subset of nodes, and moving around the graph in synchronous steps. During the process, each node successively propagates walkers visiting it along its outgoing arcs in round-robin fashion, according to a fixed ordering. We consider...
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Analysis of circular polarization antenna design trade‐offs using low‐cost EM‐driven multiobjective optimization
PublikacjaCircular polarization (CP) antennas are vital components of modern communication systems. Their design involves handling several requirements such as low reflection and axial ratio (AR) within the frequency range of interest. Small size is an important criterion for antenna mobility which is normally achieved as a by‐product of performance‐oriented modifications of the structure topology. In this work, multiobjective optimization...
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Calculations of Short-Circuit Current Flows in Earth Wires of HV Lines
PublikacjaThis paper presents a method which enables calculating flows of short-circuit currents in earth wires of high voltage transmission lines, and its implementation in the form of a computer programme. The algorithm enables performing calculations for a double-fed line and starconnected lines (three terminal lines). The developed programme enables verifying dimensioning of earth wires in the context of their short-circuit thermal withstand...
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Serial control of CNC machines
PublikacjaIn this paper a new method of the serial control of CNC machines is proposed. Actuators are controlled locally and the role of the central computer is limited to sending commands to the controller instead of sending it directly to actuators. It has been achieved with the use of the serial protocol with the use of the USB port. The taken approach leads to more reliable operation because commands are buffered and no synchronization...
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Designing a ship course controller by applying the adaptivebackstepping method
PublikacjaThe article discusses the problem of designing a proper and efficient adaptive course-keeping control system for a seagoingship based on the adaptive backstepping method. The proposed controller in the design stage takes into account thedynamic properties of the steering gear and the full nonlinear static maneuvering characteristic. The adjustable parametersof the achieved nonlinear control structure were tuned up by using the...
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Head movement compensation algorithm in multi-display communication by gaze
PublikacjaAn influence of head movements on the gaze estimation accuracy when using a head mounted eye tracking system is discussed in the paper. This issue has been examined for a multi-display environment. It was found that head movement (rotation) to some extent does not influence on the gaze estimation accuracy seriously. Acceptable results were obtained when using eye-tracker to communicate with a computer via in two displays simultaneously.
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Possible uses of crisis situation aiding system in virtual world simulation
PublikacjaMany of the real world crisis situations like spreading fire, hostile units attack, flood, and etc. are commonly used in computer games where a simulation of extensive virtual world is crucial. This paper presents some ideas for possible uses of existing crisis situation aiding system in such environments. Moreover it shows how this kind of system can be taught during subsequent games with a large number of players.
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ThreSpect – A Program for the Determination of the Appearance Energies of Neutral and Ionized Species
PublikacjaCollisions of photons and charged particles with molecules lead to their excitation, ionization, and dissociation into neutral and ionized fragments. Accurately determining thresholds of the formation of particular products plays a vital role in analyzing processes occurring during these interactions. Therefore, we present a computer program, “ThreSpect,” that allows calculating threshold energies of various species generated in...
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Application development for Android, iOS and BlackBerry mobile platforms
PublikacjaMobile devices, along with dedicated operating systems, have become a substantial and rising trend in software development. Computer industry has significantly changed in order to fulfil the needs of this new segment of the market. Authors have participated in projects, which involved programming on Android, iOS and BlackBerry operating systems. In this paper the most popular mobile platforms (and multiplatform Unity3D environment)...
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Adaptation of radar software to work with ambiguous distance measurement
PublikacjaA software extension for radar stations designed to work in the low-PRF mode that allows them to correctly measure range to targets outside of their instrumented range, is proposed. The solution does not require substantial modifications of the radar software. Additionally, we describe tools that allow one to simulate the output of a low-PRF radar observing targets that are outside its instrumented range. The proposed approach...
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Storage electric multiple units on partially electrified suburban railway lines
PublikacjaThe paper presents possible environmental, energy and economical gains implied by replacing conventional traction vehicles with independent powered electric multiple units (IPEMU) on partially electrified suburban railways. IPEMUs can operate in two modes of power supply – using overhead catenary or onboard battery storage. Appropriate computer simulations were carried out in the Matlab program, indicating the parameters of storage...
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A Surveillance Of Dynamic Processes in Selected Mechatronic Systems
PublikacjaThe paper concerns development of original method of optimal control at energy performance index and its application to dynamic processes surveillance of some mechatronic systems. The latter concerns chatter vibration surveillance during highspeed slender milling of rigid details, as well as motion control of two-wheeled mobile platform. Results of on-line computer simulations and real performance on the target objects reflect...
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Graph security testing
PublikacjaSet S ⊂ V is called secure set iff ∀ X ⊂ S | N [ X ] ∩ S | ≥ | N ( X ) \ S | [3]. That means that every subset of a secure set has at least as many friends (neighbour vertices in S) as enemies (neighbour vertices outside S) and will be defended in case of attack. Problem of determining if given set is secure is co −NP -complete, there is no efficient algorithm solving it [3]. Property testers are algorithms that distinguish inputs...
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Evaluation of Machine Learning Methods for the Experimental Classification and Clustering of Higher Education Institutions
PublikacjaHigher education institutions have a big impact on the future of skills supplied on the labour market. It means that depending on the changes in labour market, higher education institutions are making changes to fields of study or adding new ones to fulfil the demand on labour market. The significant changes on labour market caused by digital transformation, resulted in new jobs and new skills. Because of the necessity of computer...
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Measurement of luminance and color uniformity of displays using the large-format scanner
PublikacjaUniformity of display luminance and color is important for comfort and good perception of the information presented on the display. Although display technology has developed and improved a lot over the past years, different types of displays still present a challenge in selected applications, e.g. in medical use or in case of multi-screen installations. A simplified 9-point method of determining uniformity does not always produce...
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Quaternion Encryption Method for Image and Video Transmission
PublikacjaQuaternions are hyper-complex numbers of rank 4. They are often applied to mechanics in 3D space and are considered to be one of the best ways of representing rotations. In this paper a quaternion encryption method, based on algorithm by Nagase et al. (2004) has been proposed. According to a computer-based simulation the results of the performed research yield a high level of security, which is additionally strengthened by the...
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Realization, programming and controlling of the Stewart-Gough platform
PublikacjaThis paper presents realizaon, programming, and controlling of a low cost Stewart-Gough plaorm (SGP) with rotary actuators. The realized SGP is applied in a ball & plate control system. Developed dedicated software consists of embedded and applicaon soware for both the SGP posioning system and the ball & plate control. system. A ball posion is being obtained using computer vision. The paper contains tests results for both an SGP...
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Stability of softly switched multiregional dynamic output controllers with a static antiwindup filter: A discrete-time case
PublikacjaThis paper addresses the problem of model-based global stability analysis of discrete-time Takagi–Sugeno multiregional dynamic output controllers with static antiwindup filters. The presented analyses are reduced to the problem of a feasibility study of the Linear Matrix Inequalities (LMIs), derived based on Lyapunov stability theory. Two sets of LMIs are considered candidate derived from the classical common quadratic Lyapunov...
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Surrogate modeling of impedance matching transformers by means of variable‐fidelity electromagnetic simulations and nested cokriging
PublikacjaAccurate performance evaluation of microwave components can be carried out using full‐wave electromagnetic (EM) simulation tools, routinely employed for circuit verification but also in the design process itself. Unfortunately, the computational cost of EM‐driven design may be high. This is especially pertinent to tasks entailing considerable number of simulations (eg, parametric optimization, statistical analysis). A possible...
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Rendezvous of heterogeneous mobile agents in edge-weighted networks
PublikacjaWe introduce a variant of the deterministic rendezvous problem for a pair of heterogeneous agents operating in an undirected graph, which differ in the time they require to traverse particular edges of the graph. Each agent knows the complete topology of the graph and the initial positions of both agents. The agent also knows its own traversal times for all of the edges of the graph, but is unaware of the corresponding traversal...
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How to Sort Them? A Network for LEGO Bricks Classification
PublikacjaLEGO bricks are highly popular due to the ability to build almost any type of creation. This is possible thanks to availability of multiple shapes and colors of the bricks. For the smooth build process the bricks need to properly sorted and arranged. In our work we aim at creating an automated LEGO bricks sorter. With over 3700 different LEGO parts bricks classification has to be done with deep neural networks. The question arises...
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The Processing Procedure for the Interpretation of Microseismic Signal Acquired from a Surface Array During Hydraulic Fracturing in Pomerania Region in Poland
PublikacjaHydraulic fracturing is a procedure of injecting high pressure fluid into the wellbore in order to break shell rock and facilitate gas flow. It is a very costly procedure and, if not conducted properly, it may lead to environmental pollution. To avoid costs associated with pumping fluid outside the perspective (gas rich) zone and improve one’s knowledge about the reservoir rock, microseismic monitoring can be applied. The method...
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Rapid on-line method of wastewater parameters estimation by electronic nose for control and operating wastewater treatment plants toward Green Deal implementation
PublikacjaIn order to comply with legal regulations related to wastewater quality, the operational mode of facilities at wastewater treatment plant (WWTP) should be properly adjusted according to parameters of influents, however it is very difficult without frequently performed measurements. Currently there are known many techniques and devices for assesment of wastewater parameters such as chemical oxygen demand, biochemical oxygen demand,...
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How Can We Identify Electrophysiological iEEG Activities Associated with Cognitive Functions?
PublikacjaElectrophysiological activities of the brain are engaged in its various functions and give rise to a wide spectrum of low and high frequency oscillations in the intracranial EEG (iEEG) signals, commonly known as the brain waves. The iEEG spectral activities are distributed across networks of cortical and subcortical areas arranged into hierarchical processing streams. It remains a major challenge to identify these activities in...
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Data Mining Applications and Methods in Medicine
PublikacjaIn this paper we describe the research area of data mining and its applications in medicine. The origins of data mining and its crucial features are shortly presented. We discuss the specificity of medicine as an application area for computer systems. Characteristic features of the medical data are investigated. Common problems in the area are also presented as well as the strengths and capabilities of the data mining methods....
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Multimedia in teaching economics and management in higher education.
PublikacjaNowadays, the use of multimedia teaching materials at universities makes a standard practice. However their saturation is still quite low comparing to the expectations of students - the main consumers of the information contained therein. This article will present the results of research conducted among students of Management and Engineering Management carried at the Technical University of Gdańsk. Some students of Computer Science...
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Remote Monitoring System for Impedance Spectroscopy using Wireless Sensor Network
PublikacjaThe architecture of a miniaturized impedanceanalyser with wireless communication module for remoteImpedance Spectroscopy (IS) of anticorrosion coatings ondifficult-to-reach objects (e.g. on the steel construction ofthe bridge) is described in this paper. Some practical aspectsof implementation of a Wireless Sensor Network (WSN) arealso discussed. A low scale, middle range, WSN networkcomposed of a Base Station (BS) with a Personal...
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Small rov to detection and identification of dangerous underwater objects
PublikacjaA small unmanned underwater vehicle (UUV) to inspection of an undersea space is presented in the paper. Its behavior is controlled by a trained pilot. Correct detection and identification of targets depends on vehicle'sprecise displacement along a predefined route. Nowadays, the UUVs are equipped with an automatic control system to execute some basic maneuvers without constant human interventions. Hence, in the paper, an autopilot...
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Scalable Measurement System for Multiple Impedance Gas Sensors
PublikacjaAuthor proposes scalable architecture of the measurement system for gas sensor with impedance dependance of the gas concentration. The main part of the system is a single-board impedance analyser. The number of analysers working in parallel can be configured according to specific application. The system is controlled by a single computer which organises the measurement cycle and store the acquired measurement data. The system is...
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Pracujący w czasie rzeczywistym system detekcji gazów wykorzystujący przenośny komputer Raspberry PI oraz matrycę półprzewodnikowych czujników gazu
PublikacjaThe gas-analyzing systems based on the array of partially selective gas sensors and pattern-recognition techniques are potentially fast and lowcost alternative for other devices, like gas‑analysers. They give the possibility of recognition the type and the concentration of measured volatile compounds in their working environment. In this work we present the implementation of gas recognition system, in which the signals from an...
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Silent Sonar with matched filtration
PublikacjaRadars with continuous wave frequency (CW FM sonars) are used in radiolocation as 'silent sonars'. They determine the distance to target by measuring the difference between the frequency of the sounding signal and echo signal. The article presents the principle of operation and parameters of silent CW FM sonars. Target distance determined by these sonars is based on the signal at the output of the matched filter. The Doppler effect...
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Analysis of economical lighting of highways in the environment of SMOL language
PublikacjaThe paper puts forward and implements a method of designing and creating a modelling simulation environment for eztensive and complete analysis of economical lighting on highways. From a general design viewpoint, the proposed solution explores the concept of a network description language (SMOL), which has been designed to describe the necessary network functions, mechanisms, and devices; for the purpose of their computer simulation...
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Linking music data in executable documents
PublikacjaThis paper presents the application of Interactive Open Document Architecture (IODA) to music and video data. This architecture was design to create multilayer documents which consist of many files. The paper shows the method of creating media documents on the basis of IODA. These kind of documents were called IODA Media Documents (IMD). IMD have links that connect many different kinds of files containing music and video data....
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Detection of the Oocyte Orientation for the ICSI Method Automation
PublikacjaAutomation or even computer assistance of the popular infertility treatment method: ICSI (Intracytoplasmic Sperm Injection) would speed up the whole process and improve the control of the results. This paper introduces a preliminary research for automatic spermatozoon injection into the oocyte cytoplasm. Here, the method for detection a correct orientation of the polar body of the oocyte is presented. Proposed method uses deep...
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Interactive Application for Visualization of the Basic Phenomena in RF and Microwave Devices
PublikacjaAn interactive computer application visualizing the basic phenomena in RF and microwave devices is presented. Such kind of educational package can be a very helpful tool for the students as well as for the teachers (of electronics and related fields). This paper is focused on three exemplary problems only and involves: movement of electric charge, filtering of electromagnetic waves and interference phenomena in antenna arrays. The...
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An interval estimator for chlorine monitoring in drinking water distribution systems under uncertain system dynamics, inputs and chlorine concentration measurement errors
PublikacjaThe design of an interval observer for estimation of unmeasured state variables with application to drinking water distribution systems is described. In particular, the design process of such an observer is considered for estimation of the water quality described by the concentration of free chlorine. The interval observer is derived to produce the robust interval bounds on the estimated water quality state variables. The stability...
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A repeated game formulation of network embedded coding for multicast resilience in extreme conditions
PublikacjaComputer networks and data sharing applications are vital for our current society and fundamental for any available ICT solution, so that networking is considered as one of the key critical infrastructures and its correct behavior should be always enforced, even in case of disasters or severe execution conditions. Resilience is a strongly demanding nonfunctional requirement for current computer networks, and one of the key factors...
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Transfer learning in imagined speech EEG-based BCIs
PublikacjaThe Brain–Computer Interfaces (BCI) based on electroencephalograms (EEG) are systems which aim is to provide a communication channel to any person with a computer, initially it was proposed to aid people with disabilities, but actually wider applications have been proposed. These devices allow to send messages or to control devices using the brain signals. There are different neuro-paradigms which evoke brain signals of interest...
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ADAPTIVE PREDICTIONS OF THE EURO/ZŁOTY CURRENCY EXCHANGE RATE USING STATE SPACE WAVELET NETWORKS AND FORECAST COMBINATIONS
PublikacjaThe paper considers the forecasting of the euro/Polish złoty (EUR/PLN) spot exchange rate by applying state space wavelet network and econometric forecast combination models. Both prediction methods are applied to produce one-trading-day- ahead forecasts of the EUR/PLN exchange rate. The paper presents the general state space wavelet network and forecast combination models as well as their underlying principles. The state space...
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Possible uses of crisis situation aiding system in virtual world simulation
PublikacjaMany of the real world crisis situations like spreading fire, hostile units attack, flood, and etc. are commonly used in computer games where a simulation of extensive virtual world is crucial. This paper presents some ideas for possible uses of existing crisis situation aiding system in such environments. Moreover, it shows how this kind of system can be taught during subsequent games with a large number of players. As an example...
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Genetic Programming for Interaction Efficient Supporting in Volunteer Computing Systems
PublikacjaVolunteer computing systems provide a middleware for interaction between project owners and great number volunteers. In this chapter, a genetic programming paradigm has been proposed to a multi-objective scheduler design for efficient using some resources of volunteer computers via the web. In a studied problem, genetic scheduler can optimize both a workload of a bottleneck computer and cost of system. Genetic programming has been...
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MAlSim - Mobile Agent Malware Simulator
PublikacjaOne of the problems related to the simulation of attacks against critical infrastructures is the lack of adequate tools for the simulation of malicious software (malware). Malware attacks are the most frequent in the Internet and they pose a serious threat against critical networked infrastructures. To address this issue we developed Mobile Agent Malware Simulator (MAISim). The framework uses the technology of mobile agents and...
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A quaternion-based modified feistel cipher for multimedia transmission
PublikacjaIn this paper a quaternion-based modified Feistel Cipher is proposed. The algorithm is based on the scheme proposed by Sastry and Kumar (2012). Our algorithm uses special properties of quaternions to perform rotations of data sequences in 3D space for each of the cipher rounds. The plaintext (image in gray-tone) is divided into two square matrices of equal size which consist of Lipschitz quaternions. A modular arithmetic was implemented...
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Multi-criterion decision making in distributed systems by quantum evolutionary algorithms
PublikacjaDecision making by the AQMEA (Adaptive Quantum-based Multi-criterion Evolutionary Algorithm) has been considered for distributed computer systems. AQMEA has been extended by a chromosome representation with the registry of the smallest units of quantum information. Evolutionary computing with Q-bit chromosomes has been proofed to characterize by the enhanced population diversity than other representations, since individuals represent...
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Polyhedral Ramsey Numbers
PublikacjaGiven two polygons or polyhedrons P1 and P2, we can transform these figures to graphs G1 and G2, respectively. The polyhedral Ramsey number Rp(G1,G2) is the smallest integer n such that every graph, which represents polyhedron on n vertices either contains a copy of G1 or its complement contains a copy of G2. Using a computer search together with some theoretical results we have established some polyhedral Ramsey numbers, for example...
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Intelligent turbogenerator controller based on artifical neural network
PublikacjaThe paper presents a desing of an intelligent controller based on neural network (ICNN). The ICNN ensures at the same time two fundamental functions : the maintaining of generator voltage at the desired value and the damping of the electromechanical oscillations. Its performance is evaluted on a single machine infinite bus power system through computer simulations. The dynamic and transient operation of the proposed controller...
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System of protection against electric shock for circuits with power electronics converters
PublikacjaModern low voltage circuits are very often equipped with power electronics converters, therefore in these circuits non-sinusoidal earth currents (touch currents) may occur. For non-sinusoidal currents safety criteria should be modified. This paper presents these modified criteria and a computer system of protection against electric shock which can be implemented in circuits with power electronics converters. The system is based...
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Critical Remarks on Landauer’s principle of erasure– dissipation: Including notes on Maxwell demons and Szilard engines
PublikacjaWe briefly address Landauer’s Principle and some related issues in thermal demons. We show that an error-free Turing computer works in the zero-entropy limit, which proves Landauer’s derivation incorrect. To have a physical logic gate, memory or information-engine, a few essential components necessary for the operation of these devices are often neglected, such as various aspects of control, damping and the fluctuation–dissipation...
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Using Physiological Signals for Emotion Recognition
PublikacjaRecognizing user’s emotions is the promising area of research in a field of human-computer interaction. It is possible to recognize emotions using facial expression, audio signals, body poses, gestures etc. but physiological signals are very useful in this field because they are spontaneous and not controllable. In this paper a problem of using physiological signals for emotion recognition is presented. The kinds of physiological...
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Fitting the mobile device characteristics to the user's hearing preferences
PublikacjaA method for fitting the mobile computer audio characteristics to the user's hearing preferences is proposed. The process consists of two stages: calibration and dynamics processing. During the calibration phase the user performs a loudness scaling test giving their response regarding the perceived loudness. The dynamics processing made on above basis sets the loudness to the most comfortable level. The processing accounts both...