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Search results for: HYBRID PARALLEL PROGRAMMING
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Electronic structure calculations in electrolyte solutions: Methods for neutralization of extended charged interfaces
PublicationDensity functional theory (DFT) is often used for simulating extended materials such as infinite crystals or surfaces, under periodic boundary conditions (PBCs). In such calculations, when the simulation cell has non-zero charge, electrical neutrality has to be imposed, and this is often done via a uniform background charge of opposite sign (“jellium”). This artificial neutralization does not occur in reality, where a different...
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Semi-definite programming and quantum information
PublicationThis paper presents a comprehensive exploration of semi-definite programming (SDP) techniques within the context of quantum information. It examines the mathematical foundations of convex optimization, duality, and SDP formulations, providing a solid theoretical framework for addressing optimization challenges in quantum systems. By leveraging these tools, researchers and practitioners can characterize classical and quantum correlations,...
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Realization, programming and controlling of the Stewart-Gough platform
PublicationThis 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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Genetic Programming for Workload Balancing in the Comcute Grid System
PublicationA genetic programming paradigm is implemented for reliability optimization in the Comcute grid system design. Chromosomes are generated as the program functions and then genetic operators are applied for finding Pareto-suboptimal task assignment and scheduling. Results are compared with outcomes obtained by an adaptive evolutionary algorithm.
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Genetic Programming for Interaction Efficient Supporting in Volunteer Computing Systems
PublicationVolunteer 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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Properties of dimension witnesses and their semidefinite programming relaxations
PublicationIn this paper we develop a method for investigating semi-device-independent randomness expansion protocols that was introduced in Li et al. [H.-W. Li, P. Mironowicz, M. Pawłowski, Z.-Q. Yin, Y.-C. Wu, S. Wang, W. Chen, H.-G. Hu, G.-C. Guo, and Z.-F. Han, Phys. Rev. A 87, 020302(R) (2013)]. This method allows us to lower bound, with semi-definite programming, the randomness obtained from random number generators based on dimension...
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Modeling Parallel Applications in the MERPSYS Environment
PublicationThe chapter presents how to model parallel computational applications for which simulation of execution in a large-scale parallel or distributed environment is performed within the MERPSYS environment. Specifically, it is shown what approaches can be adopted to model key paradigms often used for parallel applications: master-slave, geometric parallelism (single program multiple data), pipelined and divide-and-conquer applications....
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Big Data Paradigm Developed in Volunteer Grid System with Genetic Programming Scheduler
PublicationArtificial intelligence techniques are capable to handle a large amount of information collected over the web. In this paper, big data paradigm has been studied in volunteer and grid system called Comcute that is optimized by a genetic programming scheduler. This scheduler can optimize load balancing and resource cost. Genetic programming optimizer has been applied for finding the Pareto solu-tions. Finally, some results from numerical...
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Genetic Programming with Negative Selection for Volunteer Computing System Optimization
PublicationVolunteer computing systems like BOINC or Comcute are strongly supported by a great number of volunteers who contribute resources of their computers via the Web. So, the high efficiency of such grid system is required, and that is why we have formulated a multi-criterion optimization problem for a volunteer grid system design. In that dilemma, both the cost of the host system and workload of a bottleneck host are minimized. On...
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Circularly Polarized Antenna Array design with the Potential of Gain-Size Trade-off and Omnidirectional Radiation for Millimeter-Wave Small Base Station Applications
PublicationThis paper presents the design and validation of a slot-patch-hybrid circularly polarized antenna array for 28 GHz millimeter (mm) wave (mm-wave) applications. The proposed design has a simple geometry that facilitates the fabrication process, which is otherwise a challenging task due to the sub-mm dimensions of the circuit in the mm-wave band. In the proposed structure, aperture-coupled series slot-fed array is utilized to excite...
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Practical Approach to Large-Scale Electronic Structure Calculations in Electrolyte Solutions via Continuum-Embedded Linear-Scaling Density Functional Theory
PublicationWe present the implementation of a hybrid continuum-atomistic model for including the effects of a surrounding electrolyte in large-scale density functional theory (DFT) calculations within the Order-N Electronic Total Energy Package (ONETEP) linear-scaling DFT code, which allows the simulation of large complex systems such as electrochemical interfaces. The model represents the electrolyte ions as a scalar field and the solvent...
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Modeling energy consumption of parallel applications
PublicationThe paper presents modeling and simulation of energy consumption of two types of parallel applications: geometric Single Program Multiple Data (SPMD) and divide-and-conquer (DAC). Simulation is performed in a new MERPSYS environment. Model of an application uses the Java language with extension representing message exchange between processes working in parallel. Simulation is performed by running threads representing distinct process...
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Multi-agent large-scale parallel crowd simulation
PublicationThis paper presents design, implementation and performance results of a new modular, parallel, agent-based and large scale crowd simulation environment. A parallel application, implemented with C and MPI, was implemented and run in this parallel environment for simulation and visualization of an evacuation scenario at Gdansk University of Technology, Poland and further in the area of districts of Gdansk. The application uses a...
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Parallel immune system for graph coloring
PublicationThis paper presents a parallel artificial immune system designed forgraph coloring. The algorithm is based on the clonal selection principle. Each processor operates on its own pool of antibodies and amigration mechanism is used to allow processors to exchange information. Experimental results show that migration improves the performance of the algorithm. The experiments were performed using a high performance cluster on a set...
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Selection of AHI + SC Hybrid Storage Based on Mathematical Models and Load Variation Characteristics
PublicationThe article deals with the design of a hybrid storage consisting of Aqueous Hybrid Ion battery (AHI) and supercapacitor (SC) modules. The selection of components is based on the knowledge of the load profile of the storage and the AHI battery and supercapacitor models. The paper presents the method of selecting components of the storage made of AHI batteries and supercapacitor modules The article includes an example of the hybrid...
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Parallel Computations of Text Similarities for Categorization Task
PublicationIn this chapter we describe the approach to parallel implementation of similarities in high dimensional spaces. The similarities computation have been used for textual data categorization. A test datasets we create from Wikipedia articles that with their hyper references formed a graph used in our experiments. The similarities based on Euclidean distance and Cosine measure have been used to process the data using k-means algorithm....
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NVRAM as Main Storage of Parallel File System
PublicationModern cluster environments' main trouble used to be lack of computational power provided by CPUs and GPUs, but recently they suffer more and more from insufficient performance of input and output operations. Apart from better network infrastructure and more sophisticated processing algorithms, a lot of solutions base on emerging memory technologies. This paper presents evaluation of using non-volatile random-access memory as a...
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Bounds on the Cover Time of Parallel Rotor Walks
PublicationThe 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 maintains a cyclic ordering of its outgoing arcs, and successively propagates walkers which visit it along its outgoing arcs in...
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Performance evaluation of parallel background subtraction on GPU platforms
PublicationImplementation of the background subtraction algorithm on parallel GPUs is presented. The algorithm processes video streams and extracts foreground pixels. The work focuses on optimizing parallel algorithm implementation by taking into account specific features of the GPU architecture, such as memory access, data transfers and work group organization. The algorithm is implemented in both OpenCL and CUDA. Various optimizations of...
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Block-based Representation of Application Execution on Modern Parallel Systems
PublicationThe chapter presents how to model execution of a parallel computational application that is to be executed in a large-scale parallel or distributed environment with potentially thousands to millions of execution units. The representation uses pre- viously attributes and factors representative of modern high performance systems including multicore CPUs, GPUs, dedicated accelerators such as Intel Phi.
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Simulation of parallel similarity measure computations for large data sets
PublicationThe 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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ARCHITECTURAL PROGRAMMING FOR BALANCED LOCAL URBAN CENTERS
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Experimental tests of lintel hybrid beams
PublicationThe results of experimental tests of lintel hybrid beams made of air concrete and prestressed concrete were presented in paper. Blocks of air concrete was a protective element for the construction one. The length of hybrid beams was 3.0 m, while total height 27 cm. It was assumed that hybrid beams will work in the simply-supported scheme (with a 10 cm support) loaded uniformly over the entire length. The object of the tests were...
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Selected Issues of Hybrid Outboard Motors
PublicationThe aim of the research reported in the article was designing a hybrid drive system based on an outboard internal combustion engine offered by a selected producer and testing its operating characteristics. The article presents different designs of this type of drive which can be found in the literature and are available in the market. The designed hybrid outboard drive system was tested both on the laboratory test rig and in real...
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Computer experiments with a parallel clonal selection algorithm for the graph coloring problem
PublicationArtificial 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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Bounds on the cover time of parallel rotor walks
PublicationThe 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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Dynamic soil improvement by hybrid technologies
PublicationHybrid method of subsoil improvement for road embankment foundation is described. This method is composed of two wellknown methods: dynamic replacement (DR) and microblasting (DDC) one (Deep Dynamic Compaction). The method was used for both the strengthening of the fully saturated organic subsoil as well as for acceleration of the consolidation of the organic layers. The practice ensures the expected results. A proper example on...
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Method of selecting programming practices for the safety-critical software development projects
PublicationIn recent years a plan-driven approach traditionally used in safety-critical software development has been put to a test by rapidly changing technologies, more diverse group of clients and volatile market requirements. The need to deliver good quality systems, faster and at lower cost in comparison to competitors encouraged companies to look for more efficient solutions. Agile methodologies are known to successfully address these...
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Parallel multithread computing for spectroscopic analysis in optical coherence tomography
PublicationSpectroscopic 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
PublicationThe 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
PublicationThe 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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Testbed for development and verification of hybrid localization systems
PublicationIn this paper a testbed for development and verification of hybrid localization systems is presented. It allows for systematic analysis of hybrid localization methods and speed up the development of new schemes. The proposed testbed platform is composed of subsystem for sequential data collection and testing infrastructure that can be used for investigating the localization mechanisms in controllable environment.
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Comparison of EHD devices with parallel and in series spiked electrodes
PublicationIn this paper two electrohydrodynamic (EHD) devices for gas pumping and cleaning are presented. In both cases to induce an airflow in these EHD devices corona discharge was used. The discharge was generated between the spiked electrodes set parallel (the first case) or in series (the second case) and the plate electrodes. An asymmetric electric field and generated discharge result in unidirectional gas flow through the EHD device....
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A distributed system for conducting chess games in parallel
PublicationThis 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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Quadratic programming approach to coupled resonator filter cad
PublicationArtykuł prezentuje technikę komputerowego wspomagania procesu projektowania filtrów zbliżeniowych. Polega ona na sformułowaniu macierzy sprzężeń jako problemu programowania kwadratowego (QP). Dzięki zdefiniowaniu procedury optymalizacyjnej jako problemu QP, przy założeniu liniowej zależności współczynników sprzężeń od wymiarów geometrycznych struktury, uzyskano znaczącą redukcję liczby pełnofalowych symulacji prowadzących do uzyskania...
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Multi-Objective Portfolio Optimization by Mixed Integer Programming
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Hybrid model of geared rotor system
PublicationIn the paper a hybrid model of a geared multirotor system has been developed. The model is obtained by application of both the modal decomposition methodology and the spatial discretization method. Reduced modal model was constructed for the system without gyroscopic and damping effects. The gyroscopic interaction, damping and other phenomena which are difficult to include in the modal approach were modeled by application of simply...
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From Sequential to Parallel Implementation of NLP Using the Actor Model
PublicationThe 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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Runtime Visualization of Application Progress and Monitoring of a GPU-enabled Parallel Environment
PublicationThe 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
PublicationThe 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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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...
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Parallel implementation of a Sailing Assistance Application in a Cloud Environment
PublicationSailboat 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
PublicationThe 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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HYBRID REDUCED MODEL OF ROTOR
PublicationIn the paper, the authors describe the method of model reduction of a rotor system. The proposed approach enables to obtain a low order model including e.g. nonproportional damping or the gyroscopic effect. This method is illustrated using the example of a rotor system. First, a model of the system was built without gyroscopic and damping effects by using the rigid finite element method. Next, this model was reduced. Finally, two...
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Innovative design of hybrid powered inland vessel
PublicationOne of the most demanding task for European countries is rational transportation system taking into account fuel efficient and ecological propulsion. The paper presents innovative design of hybrid powered inland vessel. The most important aspects regarding new design and technical solutions are being presented, including numerical and experimental research on hull form. Combined diesel-electric propulsion supported by solar panel...
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Suitability study of hybrid model of electrodynamic actuator
PublicationThe paper presents the proposal of the hybrid circumferential model of an electrodynamic actuator. The field model uses the inductor current as the input data which is obtained from the circumferential model or experimentally.
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Hybrid Model of Axially Moving Continua
PublicationThe paper introduces the method of the model reduction of systems that experience a Coriolis acceleration component. It causes that system equations are non-self-adjoined. To avoid such problem modal, reduced model is built up for the system without Coriolis acceleration terms which are next included by application of any lumping technique. Hence, the final reduced model is a hybrid one, obtained by both lumping and modal methods...
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Hybrid model of moving or rotating continua
PublicationThe paper introduces the method of the model reduction of systems that experience a Coriolis acceleration or gyroscopic effect component. In such causes that corresponding system equations are non-self-adjoined. Modal reduced model is built up for the system without Coriolis or gyroscopic effect terms. These phenomena are next included by application of any lumping technique. Hence, the final reduced model is a hybrid one, obtained...
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Hybrid approach to ontology specification and development
PublicationIn this chapter a first draft of a hybrid ontology development approach is presented. The context of this method encompasses the multi-agent system equipped with knowledge bases and inferring engine. The process of ontology engineering appears as a complex issue, as it addresses different point-views of both, a client and a modeler with a requirements/system analyst. Regarding this, an approach based on the knowledge preprocessing...