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Wyniki wyszukiwania dla: SERIES-PARALLEL COMPENSATION
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Simulation of parallel similarity measure computations for large data sets
PublikacjaThe paper presents our approach to implementation of similarity measure for big data analysis in a parallel environment. We describe the algorithm for parallelisation of the computations. We provide results from a real MPI application for computations of similarity measures as well as results achieved with our simulation software. The simulation environment allows us to model parallel systems of various sizes with various components...
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Metamaterial-Based Series-Fed Antenna with High Gain and Wideband Performance for Millimeter Wave Spectrum Applications
PublikacjaThis paper presents a high-gain, wideband series-fed antenna designed for 5G millimeter-wave (MMW) applications. The structure employs a substrate-integrated waveguide (SIW)-based power splitter and metamaterials (MMs). The power divider functions effectively at 27.5 GHz, exhibiting an impedance bandwidth from 26.9–28.6 GHz. The series-fed dipole is assembled on the SIW-based power splitter, incorporating four dipoles with varying...
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Dead time effects compensation strategy by third harmonic injection for a five-phase inverter
PublikacjaThis paper proposes a method for compensation of dead-time effects for a fivephase inverter. In the proposed method an additional control subsystem was added to the field-oriented control (FOC) scheme in the coordinate system mapped to the third harmonic. The additional control loop operates in the fixed, orthogonal reference frame ( α - β coordinates) without the need for additional Park transformations. The purpose of this method...
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A new multi-process collaborative architecture for time series classification
PublikacjaTime series classification (TSC) is the problem of categorizing time series data by using machine learning techniques. Its applications vary from cybersecurity and health care to remote sensing and human activity recognition. In this paper, we propose a novel multi-process collaborative architecture for TSC. The propositioned method amalgamates multi-head convolutional neural networks and capsule mechanism. In addition to the discovery...
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Dispersion compensation in optical coherence tomography
PublikacjaDyspersja wprowadzana przez system optycznej tomografii koherentnej (OCT) oraz badane obiekty powoduje zniekształcenia fazowe w zależności od długości fali widma promieniowania zastosowanego źródła optycznego. powoduje to rozmycie obrazów otrzymanych przekrojów badanych materiałów pogarszając właściwości metrologiczne systemu OCT. W artykule przedstawiono metody kompensacji dyspersji w systemie OCT oraz przedyskutowano ich właściwości.
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Parallel Programming for Modern High Performance Computing Systems
PublikacjaIn view of the growing presence and popularity of multicore and manycore processors, accelerators, and coprocessors, as well as clusters using such computing devices, the development of efficient parallel applications has become a key challenge to be able to exploit the performance of such systems. This book covers the scope of parallel programming for modern high performance computing systems. It first discusses selected and...
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Video of LEGO Bricks on Conveyor Belt Dataset Series
PublikacjaThe dataset series titled Video of LEGO bricks on conveyor belt is composed of 14 datasets containing video recordings of a moving white conveyor belt. The recordings were created using a smartphone camera in Full HD resolution. The dataset allows for the preparation of data for neural network training, and building of a LEGO sorting machine that can help builders to organise their collections.
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Compensation of Voltage Drops in Trolleybus Supply System Using Battery-Based Buffer Station
PublikacjaThis paper analyzes the results of a trial operation of a battery-based buffer station supporting a selected section of trolleybus power supply systems in Pilsen, Czech Republic. The buffer station aims to prevent the catenary from excessive voltage drops in a part of the route that is most remote from the traction substation. Compensation of voltage drops is carried out by continuously measuring the catenary voltage and injecting...
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Selection of C-Type Filters for Reactive Power Compensation and Filtration of Higher Harmonics Injected into the Transmission System by Arc Furnaces
PublikacjaThis article presents a method for selecting the elements of a C-type filter working with a conventional LC-type filter for compensating reactive power and filtering out higher harmonics generated by arc furnaces and ladle furnaces. The study was conducted in a steel mill supplied by a 110 kV transmission system, where higher harmonic currents and nonlinear loads were measured. A series of computer simulations were performed under...
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Compensation of supply current harmonics, reactive power, and unbalanced load current balance in the closed-loop control of a shunt active power filter
PublikacjaThis paper presents the compensation tasks performed by a shunt active power filter, including compensation of harmonic currents, reactive power, and an unbalanced load current. The paper demonstrates novel control of the shunt active power filter in a closed-loop system. The control algorithm was verified by performing simulations and compared the simulated results with those obtained in an open-loop control system. All simulations...
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A New Method of the Load Compensation Use During Creation of Post Blackout Start-up Path in Power System
PublikacjaIn the paper a new method of effective use of load compensation during creation of post blackout start-up path is proposed. Theoretical assumptions and simulation results of an investigation are presented. An experiment performed in the Polish Power System is also described. This experiment proved that the method proposed by the authors is advisable. The method may be utilized by power system operators for power system restoration...
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TIME SERIES DATA FOR 3D FLOOD MAPPING
PublikacjaThanks to the ability to collect information about large areas and with high frequency in time areas threatened by floods can be closely monitored. The effects of flooding are socio-economic losses. In order to reduce those losses, actions related to the determination of building zones are taken. Moreover, the conditions to be met by facilities approved for implementation in such areas are determined. Therefore, satellite data...
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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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Computer experiments with a parallel clonal selection algorithm for the graph coloring problem
PublikacjaArtificial immune systems (AIS) are algorithms that are based on the structure and mechanisms of the vertebrate immune system. Clonal selection is a process that allows lymphocytes to launch a quick response to known pathogens and to adapt to new, previously unencountered ones. This paper presents a parallel island model algorithm based on the clonal selection principles for solving the Graph Coloring Problem. The performance of...
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Parallel multithread computing for spectroscopic analysis in optical coherence tomography
PublikacjaSpectroscopic Optical Coherence Tomography (SOCT) is an extension of Optical Coherence Tomography (OCT). It allows gathering spectroscopic information from individual scattering points inside the sample. It is based on time-frequency analysis of interferometric signals. Such analysis requires calculating hundreds of Fourier transforms while performing a single A-scan. Additionally, further processing of acquired spectroscopic information...
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A Workflow Application for Parallel Processing of Big Data from an Internet Portal
PublikacjaThe paper presents a workflow application for efficient parallel processing of data downloaded from an Internet portal. The workflow partitions input files into subdirectories which are further split for parallel processing by services installed on distinct computer nodes. This way, analysis of the first ready subdirectories can start fast and is handled by services implemented as parallel multithreaded applications using multiple...
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Decentralized control of a different rated parallel UPS systems
PublikacjaThe paper presents the single phase uninterruptible power supply (UPS) system with galvanic separated DC-AC-DC-AC converters operating in parallel. The CAN physical layer based system of communication between converters has been developed and applied, which allow to utilize a decentralized master-slave control providing high availability factor of the whole UPS system. The control system of particular converters has been developed...
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DISTRIBUTED AND PARALLEL DATABASES
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Modern Platform for Parallel Algorithms Testing: Java on Intel Xeon Phi
PublikacjaParallel algorithms are popular method of increasing system performance. Apart from showing their properties using asymptotic analysis, proof-of-concept implementation and practical experiments are often required. In order to speed up the development and provide simple and easily accessible testing environment that enables execution of reliable experiments, the paper proposes a platform with multi-core computational accelerator:...
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A distributed system for conducting chess games in parallel
PublikacjaThis paper proposes a distributed and scalable cloud based system designed to play chess games in parallel. Games can be played between chess engines alone or between clusters created by combined chess engines. The system has a built-in mechanism that compares engines, based on Elo ranking which finally presents the strength of each tested approach. If an approach needs more computational power, the design of the system allows...
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A Conformal Circularly Polarized Series-Fed Microstrip Antenna Array Design
PublikacjaA conformal circularly polarized series-fed microstrip array design for broadside radiation is presented. The array aperture under design is conformal to a cylindrical surface of a given radius. The approach we present primarily addresses focusing of the circularly polarized major lobe of the conformal array by proper dimensioning of the aperture spacings. The proposed analytical models yield the values of the element spacings...
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Scheduling of compatible jobs on parallel machines
PublikacjaThe dissertation discusses the problems of scheduling compatible jobs on parallel machines. Some jobs are incompatible, which is modeled as a binary relation on the set of jobs; the relation is often modeled by an incompatibility graph. We consider two models of machines. The first model, more emphasized in the thesis, is a classical model of scheduling, where each machine does one job at time. The second one is a model of p-batching...
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From Sequential to Parallel Implementation of NLP Using the Actor Model
PublikacjaThe article focuses on presenting methods allowing easy parallelization of an existing, sequential Natural Language Processing (NLP) application within a multi-core system. The actor-based solution implemented with the Akka framework has been applied and compared to an application based on Task Parallel Library (TPL) and to the original sequential application. Architectures, data and control flows are described along with execution...
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Parallel Cooperating A-Teams
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Wideband High-Gain Low-Profile Series-Fed Antenna Integrated with Optimized Metamaterials for 5G millimeter Wave Applications
PublikacjaThis paper presents a series-fed four-dipole antenna with a broad bandwidth, high gain, and compact size for 5G millimeter wave (mm-wave) applications. The single dipole antenna provides a maximum gain of 6.2 dBi within its operational bandwidth, which ranges from 25.2 to 32.8 GHz. The proposed approach to enhance both gain and bandwidth involves a series-fed antenna design. It comprises four dipoles with varying lengths, and a...
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Runtime Visualization of Application Progress and Monitoring of a GPU-enabled Parallel Environment
PublikacjaThe paper presents design, implementation and real life uses of a visualization subsystem for a distributed framework for parallelization of workflow-based computations among clusters with nodes that feature both CPUs and GPUs. Firstly, the proposed system presents a graphical view of the infrastructure with clusters, nodes and compute devices along with parameters and runtime graphs of load, memory available, fan speeds etc. Secondly,...
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A New Approach for the Mitigating of Flow Maldistribution in Parallel Microchannel Heat Sink
PublikacjaThe problem of flow maldistribution is very critical in microchannel heat sinks (MCHS). It induces temperature nonuniformity, which may ultimately lead to the breakdown of associated system. In the present communication, a novel approach for the mitigation of flow maldistribution problem in parallel MCHS has been proposed using variable width microchannels. Numerical simulation of copper made parallel MCHS consisting of 25 channels...
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Parallel implementation of a Sailing Assistance Application in a Cloud Environment
PublikacjaSailboat weather routing is a highly complex problem in terms of both the computational time and memory. The reason for this is a large search resulting in a multitude of possible routes and a variety of user preferences. Analysing all possible routes is only feasible for small sailing regions, low-resolution maps, or sailboat movements on a grid. Therefore, various heuristic approaches are often applied, which can find solutions...
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Sensorless predictive control of three-phase parallel active filter
PublikacjaThe paper presents the control system of parallel active power filter (APF) with predictive reference current calculation and model based predictive current control. The novel estimator and predictor of grid emf is proposed for AC voltage sensorless operation of APF, regardless of distortion of this voltage. Proposed control system provides control of APF current with high precision and dynamics limited only by filter circuit parameters....
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Times Series Analysis Of Road Safety Trends At The Regional Level In Poland
PublikacjaThe paper presents possibility of applying a structural times series modeling with explanatory and intervention variables as a tool capable for explaining the changes in the monthly number of fatalities and seriously injured in traffic accidents. The analysis covers regional level and takes into consideration traffic accidents data of two regions: Pomorskie and Warmia-Mazury. In addition short-term forecasts for the two regions...
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Layer contraction of smectic liquid crystals and the compensation model
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Wow detection and compensation employing spectral processing of audio.
PublikacjaPraca zawiera opis opracowanych algorytmów detekcji i kompensacji pasożytniczych modulacji częstotliwości wynikających z nierównomiernego przesuwu nośnika dźwięku. Proponowane metody opracowano ze szczególnym uwzględnieniem przypadkowych zniekształceń drżenia obecnych w archiwalnych filmowych ścieżkach dźwiękowych. Dodatkowo algorytmy badają wpływ zniekształceń na strukturę formantową sygnałów. Analiza zmian położenia formantów...
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New algorithms for wow and flutter detection and compensation in audio
PublikacjaW referacie przedstawiono nowe metody dyskryminacji naturalnych efektów muzycznych i pasożytniczych zniekształceń drżenia dźwięku. Dodatkowo, opisano w nim metody wyznaczania przebiegu zniekształceń drżenia. Wśród nich znajdują się: detekcja okresowości sygnału w poszczególnych ramkach czasowych, śledzenie zmian przydźwięku sieciowego wykorzystujące modelowane AR widma sygnału, śledzenie zmian wysokoczęstotliwościowego prądu podkładu....
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New algorithms for wow and flutter detection and compensation in audio
PublikacjaW referacie przedstawiono nowe metody dyskryminacji naturalnych efektów muzycznych i pasożytniczych zniekształceń drżenia dźwięku. Dodatkowo, opisano w nim metody wyznaczania przebiegu zniekształceń drżenia. Wśród nich znajdują się: detekcja okresowości sygnału w poszczególnych ramkach czasowych, śledzenie zmian przydźwięku sieciowego wykorzystujące modelowane AR widma sygnału, śledzenie zmian wysokoczęstotliwościowego prądu podkładu....
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Earthquake–induced pounding on response of adjacent structures in series: experimental and numerical study
PublikacjaPounding between structures in series during earthquakes may cause serious damage in the structur-al elements. The aim of this paper is to show the results of an experimental and numerical study that is focused on pounding between more than two structures which may be called "structures in series". In this study, the shaking table experiments, as well as the numerical analyses, were performed using three tower models including...
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Parallel implementation of background subtraction algorithms for real-time video processing on a supercomputer platform
PublikacjaResults of evaluation of the background subtraction algorithms implemented on a supercomputer platform in a parallel manner are presented in the paper. The aim of the work is to chose an algorithm, a number of threads and a task scheduling method, that together provide satisfactory accuracy and efficiency of a real-time processing of high resolution camera images, maintaining the cost of resources usage at a reasonable level. Two...
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MERPSYS: An environment for simulation of parallel application execution on large scale HPC systems
PublikacjaIn this paper we present a new environment called MERPSYS that allows simulation of parallel application execution time on cluster-based systems. The environment offers a modeling application using the Java language extended with methods representing message passing type communication routines. It also offers a graphical interface for building a system model that incorporates various hardware components such as CPUs, GPUs, interconnects...
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Road safety analysis in Poland using time-series modelling techniques
PublikacjaA number of international studies argue that there is a correlation between the number of traffic fatalities and the degree of public activity. The studies use the unemployment rate to support that argument. As unemployment grows miles travelled fall, a factor known to affect road safety. This relationship seems to be true for Poland, as well. The model presented in the paper is intended to prove it. It is a structural time-series local...
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Scheduling with Complete Multipartite Incompatibility Graph on Parallel Machines
PublikacjaIn this paper we consider a problem of job scheduling on parallel machines with a presence of incompatibilities between jobs. The incompatibility relation can be modeled as a complete multipartite graph in which each edge denotes a pair of jobs that cannot be scheduled on the same machine. Our research stems from the works of Bodlaender, Jansen, and Woeginger (1994) and Bodlaender and Jansen (1993). In particular, we pursue the...
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On the Handling of Outliers in the GNSS Time Series by Means of the Noise and Probability Analysis
PublikacjaThe data pre-analysis plays a significant role in the noise determination. The most important issue is to find an optimum criterion for outliers removal, since their existence can affect any further analysis. The noises in the GNSS time series are characterized by spectral index and amplitudes that can be determined with a few different methods. In this research, the Maximum Likelihood Estimation (MLE) was used. The noise amplitudes...
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A Solution to Image Processing with Parallel MPI I/O and Distributed NVRAM Cache
PublikacjaThe paper presents a new approach to parallel image processing using byte addressable, non-volatile memory (NVRAM). We show that our custom built MPI I/O implementation of selected functions that use a distributed cache that incorporates NVRAMs located in cluster nodes can be used for efficient processing of large images. We demonstrate performance benefits of such a solution compared to a traditional implementation without NVRAM...
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Implementation of FDTD-compatible Green's function on heterogeneous CPU-GPU parallel processing system
PublikacjaThis paper presents an implementation of the FDTD-compatible Green's function on a heterogeneous parallel processing system. The developed implementation simultaneously utilizes computational power of the central processing unit (CPU) and the graphics processing unit (GPU) to the computational tasks best suited to each architecture. Recently, closed-form expression for this discrete Green's function (DGF) was derived, which facilitates...
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Assessment of OpenMP Master–Slave Implementations for Selected Irregular Parallel Applications
PublikacjaThe paper investigates various implementations of a master–slave paradigm using the popular OpenMP API and relative performance of the former using modern multi-core workstation CPUs. It is assumed that a master partitions available input into a batch of predefined number of data chunks which are then processed in parallel by a set of slaves and the procedure is repeated until all input data has been processed. The paper experimentally...
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Performance Evaluation of the Parallel Codebook Algorithm for Background Subtraction in Video Stream
PublikacjaA background subtraction algorithm based on the codebook approach was implemented on a multi-core processor in a parallel form, using the OpenMP system. The aim of the experiments was to evaluate performance of the multithreaded algorithm in processing video streams recorded from monitoring cameras, depending on a number of computer cores used, method of task scheduling, image resolution and degree of image content variability....
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A Parallel Genetic Algorithm for Creating Virtual Portraits of Historical Figures
PublikacjaIn this paper we present a genetic algorithm (GA) for creating hypothetical virtual portraits of historical figures and other individuals whose facial appearance is unknown. Our algorithm uses existing portraits of random people from specific historical period and social background to evolve a set of face images potentially resembling the person whose image is to be found. We then use portraits of the person's relatives to judge...
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Parallel processing of multimedia streams
PublikacjaRozdział przedstawia platformę KASKADA służącą do przetwarzania strumieni multimedialnych. Został opisany jej projekt: diagramy UML klas i sekwencji obrazujące mechanizmy przetwarzania strumieni, oraz szczegóły komunikacji. Zaprezentowano, również, specjalistyczny framework wspomagający tworzenie i wykonywanie algorytmów, jak również definiowanie scenariuszy usług, wraz z oceną ich użyteczności.
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Parallel scheduling by graph ranking
PublikacjaNr dokum.: 73017Praca dotyczy jednego z nieklasycznych modeli kolorowania grafów - uporządkowanego kolorowania. Celem było uzyskanie wyników, które mogo być wykorzystane w praktycznych zastosowaniach tego modelu, do których należą: równoległe przetwarzanie zapytań w relacyjnych bazach danych, równoległa faktoryzacja macierzy metodą Choleskiego, równoległa asemblacja produktu z jego części składowych. W pracy wskazano uogólnienia...
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Parallel processing of multimedia streams
PublikacjaW artykule zaprezentowana jest nowa biblioteka wspierającą tworzenie zadań obliczeniowych, część platformy KASKADA.Przedstawiony został projekt biblioteki, uwzględniający diagram głównych klas oraz diagram sekwencji. Drugi z diagramów ukazuje współpracę głównych klas w procesie przetwarzania strumieni multimedialnych. W dalszej częsci omówione zostały szczegły mechanizmu komunikacji międzyzadawniowej oraz przedstawiony został graf...
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Conformance testing of parallel languages
PublikacjaPrzedstawiono propozycję formalizacji opisu procesu generacji, wykonania ioceny testów zgodności dla języków i bibliotek programowania równoległego, wzakresie zgodności funkcjonalnej i wydajnościowej. Przykłady ilustrujące proponowany formalizm wykorzystują platformę programowania Athapascan.
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Performance evaluation of the parallel object tracking algorithm employing the particle filter
PublikacjaAn algorithm based on particle filters is employed to track moving objects in video streams from fixed and non-fixed cameras. Particle weighting is based on color histograms computed in the iHLS color space. Particle computations are parallelized with CUDA framework. The algorithm was tested on various GPU devices: a desktop GPU card, a mobile chipset and two embedded GPU platforms. The processing speed depending on the number...