Wyszukiwarka
Wyniki wyszukiwania dla: grid system
-
Genetic Programming with Negative Selection for Volunteer Computing System Optimization
PublikacjaVolunteer 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...
-
Bondage number of grid graphs
PublikacjaThe bondage number b(G) of a nonempty graph G is the cardinality of a smallest set of edges whose removal from G results in a graph with domination number greater than the domination number of G. Here we study the bondage number of some grid-like graphs. In this sense, we obtain some bounds or exact values of the bondage number of some strong product and direct product of two paths.
-
Grid Implementation of a Parallel Multiobjective Genetic Algorithm for Optimized Allocation of Chlorination Stations in Drinking Water Distribution Systems: Chojnice Case Study
PublikacjaSolving multiobjective optimization problems requires suitable algorithms to find a satisfactory approximation of a globally optimal Pareto front. Furthermore, it is a computationally demanding task. In this paper, the grid implementation of a distributed multiobjective genetic algorithm is presented. The distributed version of the algorithm is based on the island algorithm with forgetting island elitism used instead of a genetic...
-
Monitoring system of the road embankment
PublikacjaThe paper presents the monitoring system of the embankment supported on concrete columns and overlaid by a load transfer platform (LTP) with the embedded steel grid. This field investigation was to study the complex inter-action between the columns, the LTP layer, and steel reinforcement via full-scale in situ measurements during erection of the embankment. The study was focused on the behaviour of steel reinforcement and the behaviour...
-
Modelling Long‐Term Transition from Coal‐Reliant to Low‐Emission Power Grid and District Heating Systems in Poland
PublikacjaEnergy systems require technological changes towards climate neutrality. In Poland, where the power system is dominated by outdated coal-fired power plants, efforts to minimize the environmental impact are associated with high costs. Therefore, optimal paths for the development of the energy sector should be sought in order to achieve ambitious long-term strategic goals, while minimizing the negative impact on the consumers’ home...
-
Meta-computations on the CLUSTERIX Grid
Publikacja -
Volunteer Computing System Comcute with Smart Scheduler
PublikacjaIn this paper, a volunteer grid called Comcute is studied. Moreover, the harmony search scheduler is proposed. This scheduler has been designed for efficient using some resources of volunteer grid. The harmony search scheduler optimizes both a workload of a bottleneck computer and the cost of grid. Finally, some experiment outcomes have been discussed.
-
Jarosław Guziński prof. dr hab. inż.
OsobySTOPNIE NAUKOWE 2021 Tytuł profesora nauk inżynieryjno-technicznych. 2012 Stopień doktora habilitowanego nauk technicznych – Wydział Elektrotechniki i Automatyki PG. Rozprawa habilitacyjna „Układy napędowe z silnikami indukcyjnymi i filtrami wyjściowymi falowników. Zagadnienia wybrane”. Kolokwium i nadanie stopnia doktora habilitowanego 29 maja 2012 r. Monografia uzyskała nagrodę naukową Wydziału IV Nauk Technicznych Polskiej...
-
Genetic Positioning of Fire Stations Utilizing Grid-computing Platform
PublikacjaA chapter presents a model for determining near-optimal locations of fire stations based on topography of a given area and location of forests, rivers, lakes and other elements of the site. The model is based on principals of genetic algorithms and utilizes the power of the grid to distribute and execute in parallel most performance-demanding computations involved in the algorithm.
-
Simplified Distribution Grid Modelling for Connection Analyses
PublikacjaThis paper considers the modelling of medium and low voltage grids for the purpose of connection studies by distribution grid operators. Possible simplifications in grid modelling are discussed, which are acceptable from the viewpoint of the final result. The main driver of the modelling simplification is the MS Excel environment used as the computation platform, and the limitation of time for grid modelling.
-
Standards on Cyber Security Assessment of Smart Grid
PublikacjaSecurity evaluation of communication systems in smart grid poses a great challenge to the developers and operators. In recent years many new smart grid standards were proposed, which paradoxically results in the difficulty in finding a relevant publication in this plethora of literature. This paper presents the results of a systematic analysis which aimed at addressing this issue by identifying standards that present sound security...
-
Toward knowledge-grid model for academic purposes
PublikacjaNowadays we face a huge amount of data and information sharing on the Web by different users worldwide. For example, the academic environment is one of such places where teachers share and manage knowledge for groups of students. This paper proposes a multi-dimensional knowledge space model, designed to distribute and manage knowledge resources efficiently. We view our model as a foundation of a knowledge grid platform. Two crucial...
-
Power control system structure of doubly‐fed induction generator connected to current source converter
PublikacjaThe power control system structures for a doubly-fed generator (DFIG) are proposed. The classical field oriented control and the feedback control with the multi-scalar variables were considered. The generator is working in the AC grid connection mode. The rotor side of the generator is connected to the current source converter (CSC); the stator is directly related to the AC grid. The static feedback linearization using the multi-scalar...
-
Analysis of the Impact of Charging Electric Cars on the Power System Load
PublikacjaThe paper presents ways of integrating electric cars with the power system. In connection with this, daily load curves in the average working day have been developed in the G2V (Grid-to-Vehicle) and V2G (Vehicle-to-Grid) variants. The G2V solution consists in unidirectional energy flow from the power system to a vehicle’s battery. The V2G solution consists in bi-directional energy exchange between the power system and electric...
-
A Review of Standards with Cybersecurity Requirements for Smart Grid
PublikacjaAssuring cybersecurity of the smart grid is indispensable for the reliable operation of this new form of the electricity network. Experts agree that standardised solutions and practices should be applied in the first place. In recent years many new standards for smart grids have been published, which paradoxically results in the difficulty of finding a relevant publication in this plethora of literature. This paper presents results...
-
Knowledge-Grid Modelling for Academic Purposes
PublikacjaNowadays, we face a huge amount of data and information sharing on the Web by different users worldwide. A multidimensional perspective in describing a university ontology seems to be very important for the modelling of higher education resources. This paper proposes a multi-dimensional knowledge model, designed to distribute and manage knowledge resources efficiently. We propose our model as the foundation of an advanced knowledge...
-
Dobór elementów instalacji fotowoltaicznych - instalacje on-grid
PublikacjaObecnie instalacje fotowoltaiczne dołączone do sieci stanowią 72% wszystkich systemów fotowoltaicznych.System PV podłączony do sieci elektroenergetycznej wytwarza energię, która jest w sposób ciągły przekazywana do sieci, co (przeciwnie niż w instalacjach off-grid) pozwala na całkowite niedopasowanie liczby zamontowanych w instalacji modułów fotowoltaicznych do zapotrzebowania obiektu na energię elektryczną. W efekcie instalacja...
-
Voltage Conditions in Low Voltage Grid with Connected Mictogeneration
PublikacjaThe introduction of distributed generation into a low voltage grid may cause voltage problems in it. The paper discusses the effect of microgeneration on voltage levels in a low voltage grid. A real low voltage grid of considerable length was selected for the analysis. The grid primarily supplies residential buildings in a rural area. Results of tests that consider potential measures which could be applied in this grid to improve...
-
Waldemar Korłub dr inż.
OsobyWaldemar Korłub uzyskał tytuł inżyniera w 2011 roku, tytuł magistra w 2012 roku oraz stopień doktora w dyscyplinie informatyki w 2017 roku na Wydziale Elektroniki Telekomunikacji i Informatyki Politechniki Gdańskiej. Jego zainteresowania naukowe obejmują: systemy rozproszone ze szczególnym uwzględnieniem systemów typu grid i chmur obliczeniowych, systemy autonomiczne zdolne do samodzielnej optymalizacji, zarządzania zasobami, ochrony...
-
Comprehensive distortion compensation of grid-connected inverter currents
PublikacjaThe paper presents a comprehensive approach to the compensation of phase current distortion of grid-connected power inverters. Four different sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, voltage fluctuations in the dc link, time delays in the estimation of grid voltages, and the distortion of inverter output voltages due to dead-time effects and related...
-
Decentralized Microgrid Energy Management System with Market-Based Energy Trade System
PublikacjaThis paper presents a decentralized energy management system for a power microgrid, which integrates individual users, who own renewable energy sources and energy storages. The purpose of the system is to make optimal use of available resources to cover the electricity needs of the whole microgrid. Thanks to the energy exchange system, in addition to exchanges with the distribution network, the system also allows trades within...
-
Standards with cybersecurity controls for smart grid - A systematic analysis
PublikacjaIn recent years numerous standards related to the cybersecurity of smart grids have been published, which led to the challenge for operators in obtaining indications that match their specific objectives and contexts. Although several studies approached this problem by providing more or less comprehensive surveys and overviews of smart grid cybersecurity standards, none of them was dedicated to the actual and important subject of...
-
Optymalizacja równoważenia obciążeń w systemach klasy grid
PublikacjaZaprezentowano techniki równoważenia obciążeń testowane w systemie rozproszonym Comcute o architekturze typu grid. Omówiono niezbędne uwarunkowania środowiska prowadzenia obliczeń w zestawie laboratoryjnym Politechniki Gdańskiej, a także odniesiono się do kryteriów kierunkujących równoważenie obciążeń. Przedstawiono wielopoziomową metodę równoważenia obciążeń.
-
Distributed Detection of Selected Features in Data Streams Using Grid-class Systems
PublikacjaThis chapter describes basic methodology of distributed digital signal processing. A choice of distributed methods of detection of selected features in data streams using grid-class systems is discussed. Problems related to distribution of data for processing are addressed. A mitigating method for data distribution and result merging is described.
-
A high-accuracy complex-phase method of simulating X-ray propagation through a multi-lens system
PublikacjaThe propagation of X-ray waves through an optical system consisting of many X-ray refractive lenses is considered. For solving the problem for an electromagnetic wave, a finite-difference method is applied. The error of simulation is analytically estimated and investigated. It was found that a very detailed difference grid is required for reliable and accurate calculations of the propagation of X-ray waves through a multi-lens...
-
Application of Traction Supply System for Charging Electric Cars
PublikacjaThe development of electromobility involves the development of electric cars charging infrastructure. The increase of the number of chargers poses new demands for the AC power grid, especially in regard to its capacity of delivering high peak power. As an alternative for the public AC power grid, urban electrified transportation systems (trams, trolleybuses, and metro) can be used for supplying electric cars chargers. The article...
-
The Impact of Micro-Sources on Voltage Distortions in a Power Grid
PublikacjaThe increase in the number of photovoltaic (PV) systems integrated with low voltage (LV) grids has led to a great need to analyse the impact of these systems on the quality of electricity and the reliability of its supply. This paper presents and compares the energy quality requirements imposed by various countries on photovoltaic plants. Then, based on real object tests and simulation in DIgSILENT PowerFactory, the impact has...
-
Object oriented grid computing for computational electromagnetics
PublikacjaArtykuł opisuje bibliotekę WiCommGrid napisaną w języku java, która realizuje ideę wymiany informacji pomiędzy węzłami środowiska rozproszonego z zastosowaniem programowania zorientowanego obiektowo. Biblioteka ta przystosowana jest do współdziałania z wieloma systemami operacyjnymi oraz z rożnym środowiskiem sprzętowym. Zbudowaną aplikację zastosowano do zrównoleglonych obliczeń rozkładu pola elektromagnetycznego w oparciu o algorytm...
-
New fast photomultipliers with a screening grid at the anode
Publikacja -
A Point Set Connection Problem for Autonomous Mobile Robots in a Grid
PublikacjaConsider an orthogonal grid of streets and avenues in a Manhattan-like city populated by stationary sensor modules at some intersections and mobile robots that can serve as relays of information that the modules exchange, where both module-module and module-robot communication is limited to a straight line of sight within the grid. The robots are oblivious and move asynchronously. We present a distributed algorithm that, given...
-
A Paradigm for HV, MV, LV Distribution Grid Development Planning
PublikacjaIn the literature, including that relating to businesses in the energy (and power) sector, the concept of these organizations’ operating paradigm may be found. The paper discusses the concept of the paradigm, with a focus on the power grid development planning paradigm. Against this background, issues related to energy security and power systems development trends and problems are presented. A new paradigm is proposed for distribution...
-
Application of PL-Grid Platform for Modeling of the Selected Acoustic Phenomena
PublikacjaDomain grids are specific computational environments, developed within the PLGrid Plus project. For the Acoustic domain grid two supercomputer grid based services were prepared. Dedicated software consists of the outdoor sound propagation module and psychoacoustical noise dosimeter. The results are presented in a form of maps of sound level and Temporary Threshold Shift (TTS) values, therefore the services may play an informative...
-
Estimation of the Maximum Permissible PV Power to be Connected to the MV Grid
PublikacjaIn recent decades, a significant increase in the share of renewable energy sources in power grids at various voltage levels has been observed. A number of articles have been published highlighting emerging problems in low-voltage grids with a large share of prosumers and in medium- and high-voltage grids to which photovoltaic (PV) plants are connected. The article analyzes the medium-voltage grid in terms of the possibility of...
-
Use of AMI Meters in the Process of Low Voltage Grid Optimization
PublikacjaThis is a report of a project involving, inter alia, low voltage grid performance optimization with data from AMI meters . The study was supported with a European UPGRID grant, and executed by a consortium of companies from seven European countries, including Poland .
-
Distributed System For Noise Threat Evaluation Based On Psychoacoustic Measurements
PublikacjaAn innovative system designed for the continuous monitoring of acoustic climate of urban areas was presentedin the paper. The assessment of environmental threats is performed using online data, acquired through a grid ofengineered monitoring stations collecting comprehensive information about the acoustic climate of urban areas.The grid of proposed devices provides valuable data for the purpose of long and short time acoustic climateanalysis....
-
Security Information Sharing for the Polish Power System
PublikacjaThe Polish Power System is becoming increasingly more dependent on Information and Communication Technologies which results in its exposure to cyberattacks, including the evolved and highly sophisticated threats such as Advanced Persistent Threats or Distributed Denial of Service attacks. The most exposed components are SCADA systems in substations and Distributed Control Systems in power plants. When addressing this situation...
-
Comprehensive compensation of grid current distortion by shunt active power filters
PublikacjaThe paper presents a comprehensive approach to the compensation of grid current distortion in shunt active power filter systems. Four sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the evaluation of grid voltages and computation of compensating currents, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due...
-
Flexibility and user‐friendliness of Grid portals: the PROGRESS approach
Publikacja -
An Overview of Bidirectional EV Chargers: Empowering Traction Grid-Powered Chargers
PublikacjaIn recent years, the number of electric vehicles has been at least doubling year after year. As a result, today electric vehicles already account for approximately 10% of the global automotive market, which positively affects environment in urbanized areas. However, to take full advantage of the EV integration it is necessary to use renewable sources for their charging; optimally place charging stations/terminals; optimally manage...
-
Single-phase power electronics transformer with active functions for smart grid
PublikacjaThis paper presents the control of one cell of a modular single-phase power electronics transformer with active functions for meeting the smart grid concept. In this way, the converter could be used not only as a conventional transformer but also for grid such as reactive power, harmonic elimination and energy storage. The topology of the cell is composed by a bidirectional converter with three stages: a half bridge in the input...
-
Wybrane rozwiązania występujące w architekturach systemów rozproszonych klasy grid
PublikacjaOpisano wybrane rozwiązania występujące w architekturach systemów rozproszonych klasy grid. Odniesiono się do zapewnienia przezroczystości, a także do możliwości zarządzania i kontroli wykorzystania zasobów. Omówiono zasady optymalizacji zarządzania takimi systemami.
-
The finite-difference simulation of x-rays propagation through a system of lenses
PublikacjaThe propagation of X-ray waves through an optical system consisting of 33 aluminum X-ray refractive lenses is considered. For solving the problem, a finite-difference method is suggested and investigated. It is shown that very small steps of the difference grid are necessary for reliable computation of propagation of X-ray waves through the system of lenses. It is shown that the wave phase is a function very quickly increasing...
-
Crowdsourcing and Volunteer Computing as Distributed Approach for Problem Solving
PublikacjaIn this paper, a combination between volunteer computing and crowdsourcing is presented. Two paradigms of the web computing are described, analyzed and compared in detail: grid computing and volunteer computing. Characteristics of BOINC and its contribution to global Internet processing are shown with the stress put onto applications the system can facilitate and problems it can solve. An alternative instance of a grid computing...
-
Cooperation of a Non-Linear Receiver with a Three-Phase Power Grid
Publikacja -
LabVIEW-based intelligent system of protection against electric shock for photovoltaic installations
PublikacjaEvaluation of shock hazard in installations with photovoltaic sources of energy is more complicated than in a conventional low voltage system. In case of earth fault in photovoltaic generators, that are connected to the AC power public grid, a composite waveform of earth fault current in the installation may occur. For composite waveforms, the safety criteria should be modified. The paper considers the effect of the composite waveforms...
-
A Wind Energy Conversion System Based on a Generator with Modulated Magnetic Flux
PublikacjaIn this work, the concept of an energy conversion system for wind turbines based on the modified permanent magnet synchronous generator (PMSG) is presented. In the generator, a pair of three-phase windings is used, one of which is connected in a “star” and the second in a “delta” configuration. At the outputs of both windings, two six-pulse uncontrolled (diode) rectifiers are included. These rectifiers are mutually coupled by a...
-
A high-accuracy method of computation of x-ray waves propagation through an optical system consisting of many lenses
PublikacjaThe propagation of X-ray waves through an optical system consisting of many X-ray refractive lenses is considered. Two differential equations are contemplated for solving the problem for electromagnetic wave propagation: first – an equation for the electric field, second – an equation derived for a complex phase of an electric field. Both equations are solved by the use of a finite-difference method. The simulation error is estimated...
-
Techniki audytowania zabezpieczeń sieci bezprzewodowej z wykorzystaniem systemów klasy grid
PublikacjaZaprezentowano efektywne zasady weryfikacji zabezpieczeń sieci bezprzewodowych z wykorzystaniem oprogramowania Back/Track w dystrybucji systemu Linux. Omówiono algorytmy RC4, MIC i AES, które wspierają techniki zabezpieczeń WEP, WPA i WPA2 wchodzące w skład protokołu IEEW 802.11. Zamieszczano także opis wykorzystania systemu rozproszonego Comcute o architekturze typu grid do prowadzenia audytu bezprzewodowej sieci.
-
Optimisation of cooperation of hybrid renewable energy sources with hydrogen energy storage toward the lowest net present cost
PublikacjaThe paper presents the results of a technical and economic analysis of the power supply for a model industrial facility based on intermittent renewable energy sources in the form of wind turbines and photovoltaic modules, supplemented with hydrogen energy storage. The adopted power supply strategy assumed the maximisation of self-consumption of self-produced electricity. Six variants were considered, including two with an energy...
-
Smart MV/LV distribution transformer for Smart Grid with active prosumer participation
PublikacjaWraz z rozwojem sieci dystrybucyjnych i ich stopniowym przekształcaniem w inteligentne sieci typu Smart Grid będzie rosłoznaczenie i udział sterowanych układów przekształtnikowych mocy stosowanych jako interfejsy pomiędzy źródłami energii a sieciąoraz pomiędzy siecią a odbiorcami. W artykule rozwinięto koncepcję wymiany konwencjonalnych transformatorów dystrybucyjnych50 Hz na inteligentne transformatory dystrybucyjne. Zaproponowano...