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Evaluation of Open Source SIEM for Situation Awareness Platform in the Smart Grid Environment
PublicationThe smart grid as a large-scale system of systems has an exceptionally large surface exposed to cyber-attacks, including highly evolved and sophisticated threats such as Advanced Persistent Threats (APT) or Botnets. When addressing this situation the usual cyber security technologies are prerequisite, but not sufficient. The smart grid requires developing and deploying an extensive ICT infrastructure that supports significantly...
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Verification of safety in low-voltage power systems without nuisance tripping of residual current devices
PublicationLow-voltage power systems require initial and periodical verification to check the effectiveness of protection against electric shock. As a protection in case of fault, automatic disconnection of supply is most often used. To verify such a protection measure, the earth fault loop impedance or resistance is measured. This measurement is easy to perform in circuits without residual current devices. When residual current devices are...
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Current trends in the field of steganalysis and guidelines for constructions of new steganalysis schemes
PublicationThe paper concerns blind steganalysis techniques in the passive steganalysis scenario designed to detect the steganographic cover modification schemes. The goal is to investigate the state-of-art in the field of steganalysis, and, above all, to recognize current trends existing in this field and determine guidelines for constructions of new steganalysis schemes. The intended effects are to examine the possibilities for the development...
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Effect of soil moisture on current-carrying capacity of low-voltage power cables
PublicationOne of the factors affecting current-carrying capacity of underground power cables is the thermal resistivity of soil. Its value in the close proximity of the cable is the most important, and for this reason, in some cases, the local soil is replaced with an another soil type or with a cement-sand mixture. The thermal resistivity of the soil is strongly affected by moisture, and in the case of a cement-sand mixture – as tested...
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A new method of fault loop resistance measurement in low voltage systems with residual current devices
PublicationThis paper presents a new method of fault loop resistance measurement in low voltage systems with residual current devices. The method enables measuring fault loop resistance without nuisance tripping of residual current devices, by application an unconventional waveform of measurement current. It is important for proper verification of the effectiveness of protection against electric shock.
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Output voltage, current and DC-link voltages under SVPWM, experimental results
Open Research DataThe dataset contains the experimental results of the project: A universal algorithm of space vector pulse width modulation for three-level three and multi-phase NPC inverters with DC-link voltage balancing. The output line-to-line voltage, output current and DC-link voltages were included. The comparison studies between proposed Space Vector Pulse-Width...
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Output voltage, current and DC-link voltages under SPWM, experimental results
Open Research DataThe dataset contains the experimental results of the project: A universal algorithm of space vector pulse width modulation for three-level three and multi-phase NPC inverters with DC-link voltage balancing. The output line-to-line voltage, output current and DC-link voltages were included. The Carrier-Based Pulse-Width Modulation (CBPWM) technique was...
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Realizacja systemu zarządzania wydziałem wyższej uczelni w technologiach typu open-source
PublicationW artykule przedstawiono założenia projektowe, architekturę i implementację systemu przeznaczonego do wspomagania zarządzania wydziałem wyższej uczelni. System jest realizowany dla Wydziału Elektroniki, Telekomunikacji i Informatyki Politechniki Gdańskiej, w technologiach typu open-source. Artykuł opisuje poszczególne komponenty systemu oraz aspekty technologiczne jego budowy. Opisano założenia przyjęte na początku projektu, architekturę...
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Tripping of F-type RCDs for sinusoidal residual current with superimposed smooth DC component
PublicationRecent trends in green energy development make that photovoltaics and electric vehicles are applied on an increasing scale. In both photovoltaic and electric vehicle charging installations, a significant value of DC component of the earth fault current may appear, which is a challenge, in particular, for commonly used residual current devices (RCDs). This paper presents results of the laboratory test on the operation of F-type...
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Particulate Matter Production of Small Heat Source Depending on the Bark Content in Wood Pellets
PublicationWood pellets as biofuel are more and more used in small heat sources in Europe. Standard wood pellets are produced from wood sawdust without bark. The paper deals about the impact of bark in wood pellets on their properties and combustion process. Special attention in this work is paid to production of particulate matter during combustion of wood pellets depending on bark content. There were experimentally produced spruce wood...
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Young shoots of red cabbage are a better source of selected nutrients and glucosinolates in comparison to the vegetable at full maturity
PublicationCruciferous vegetables are a valuable source of ingredients with health benefits. The most characteristic compounds of cruciferous vegetables with identified anticancer properties are glucosinolates. Young shoots and sprouts of red cabbage are becoming a popular fresh food rich in nutrients and bioactive compounds. The objective of this research was to determine, for the first time in a comprehensive approach, whether young shoots...
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Identification of the Contamination Source Location in the Drinking Water Distribution System Based on the Neural Network Classifier
PublicationThe contamination ingression to the Water Distribution System (WDS) may have a major impact on the drinking water consumers health. In the case of the WDS contamination the data from the water quality sensors may be efficiently used for the appropriate disaster management. In this paper the methodology based on the Learning Vector Quantization (LVQ) neural network classifier for the identification of the contamination source location...
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Sensorless IPMSM drive with rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes a sensorless Interior Permanent Magnet Synchronous Motor (IPMSM) drive designed for traction applications. Wide-speed sensorless operation is provided with the use of three methods of rotor position estimation designed for: a standstill, low- and high-speed range. The paper focuses on the high-speed estimation algorithm. The estimator uses the derivatives of motor phase currentsresulting from PWM modulation...
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Experimental verification of a new method of loop resistance testing in low voltage systems with residual current devices
PublicationA periodical verification of the effectiveness of protection against electric shock shall be performed in low voltage systems. The scope of this verification includes loop impedance/resistance testing. If a residual current device is installed in a tested circuit, this testing is problematic. A residual current device trips out during the test, because of the high value of measurement current. This precludes the execution of the...
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Voltage and Current Unbalance Reduction in Power Networks with Distributed Generation and Electric Vehicles
PublicationThe current development of prosumer microsources and the expected spread of electric vehicles may cause the appearance of significant current and voltage unbalance in low-voltage (LV) networks. This unbalance, which is an unfavorable phenomenon, may occur when using single-phase photovoltaic (PV) microsources and single-phase home chargers for electric vehicles. This paper presents a proposal for the symmetrization of the LV network...
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Elimination of the negative effect of earth fault current higher frequency on tripping of residual current devices
PublicationCzęstotliwość prądu różnicowego większa niż 50/60 Hz ma niekorzystny wpływ na wyzwalanie wyłączników różnicowoprądowych. Przy zwiększonej częstotliwości prądu różnicowego rzeczywisty prąd zadziałania wyłączników zwiększa się, a niektóre z nich w ogóle nie wyzwalają. W artykule omówiono główne przyczyny zwiększenia się prądu zadziałania wyłączników różnicowoprądowych oraz przedstawiono sposób eliminacji niekorzystnego wpływu zwiększonej...
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CFD-based evaluation of current-carrying capacity of power cables installed in free air
PublicationEvaluation of current-carrying capacity of power cables and selection of cross-sectional area of their conductors are mainly performed in accordance with requirements of EN, IEC or IEEE standards. However, these standards do not provide all methods of cables installation and location which occur in practice. Thus, in some cases, performance of advanced modeling of various thermal phenomena, affecting power cables current-carrying...
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RAPESEED PELLET - A BYPRODUCT OF BIODIESEL PRODUCTION - AS AN EXCELLENT RENEWABLE ENERGY SOURCE
PublicationVegetable oils are renewable feedstock currently being used for production of biofuels from sustainable biomass resources. The existing technology for producing diesel fuel from plant oils, such as rapeseed, soybean, canola and palm oil are largely centered on transesterification of oils with methanol to produce fatty acid methyl esters (FAME) or biodiesel. Rapeseed pellet - crushed seed residue from oil extraction is a byproduct...
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Wear estimation of current collector contact strips by analysis of a 3D scanning results
PublicationThe technical condition of current collector contact strips is very important when operational reliability of railway transportation is considered. The authors proposed a novel measurement system based on a 3D camera to register the shape and dimensions of the current collector contact strips surface. The system was installed above the railway track for tests in target ambient. During the trial operation a few dozen of contact...
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Usługi Third Party Call Control zrealizowane z wykorzystaniem oprogramowania Open Source
PublicationKoncepcja sieci NGN zakłada otwartość na usługi udostępniane użytkownikom (abonentom). Jej realizacja wymaga ulokowania tej funkcjonalności w zewnętrznych elementach w stosunku do sieci telekomunikacyjnej udostępniającej usługi przenoszenia. Jednym z rozwiązań jest serwer Third Party Call Control (3PCC) w którym można ulokować scenariusze sterowania przebiegiem połączenia. W artykule przedstawiono i omówiono projekt, wykonany w...
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Modal analysis of railway current collectors using Autodesk Inventor
PublicationThe paper presents the results of modal analysis of railway current collector type 160EC. In the first place, the analysis was carried out analytically for a simplified two lumped mass pantograph model. Then numerical analysis was conducted in the Autodesk Inventor (AI) on the prepared multibody model using the AI modal analysis algorithm, which is based on the finite element method (FEM). Model elements which are most relevant...
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Electrical safety in low-voltage DC microgrids with B-type residual current devices
PublicationResidual current devices (RCDs) are most popular devices used in low-voltage installations for protection against electric shock and fire. In cases of high risk of electric shock the application of RCDs is mandatory. Currently, the spread of local direct current (DC) microgrids is widely considered. This creates new challenges for protective systems, in particular those based on RCDs. The main purpose of the research is to test...
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Application of atmospheric pressure microwave plasma source for hydrogen production from ethanol
PublicationIn contrast to conventional technologies of hydrogen production like water electrolysis or coal gasification we propose a method based on the atmospheric pressure microwave plasma. In this paper we present results of the experimental investigations of the hydrogen production from ethanol in the atmospheric pressure plasma generated in waveguidesupplied cylindrical type nozzleless microwave (915 MHz and 2.45 GHz) plasma source (MPS)....
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Design solution and selected research results of the sea-wave energy converter
PublicationW artykule przedstawiono oryginalne rozwiązanie konstrukcyjne boi do pozyskiwania energii fal morskich oraz analizy i badania modelowe turbiny wodnej poprzedzające wybór ostateczny konstrukcji modelu boi w skali 1:5 przewidzianego do badań eksperymentalnych w basenie holowniczym. Zaprezentowano także wybrane wyniki badań modelowych i symulacji komputerowych ukazujący wpływ systemu kotwiczenia i innych parametrów na jakość i efektywność...
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Impact of Low Switching-to-Fundamental Frequency Ratio on Predictive Current Control of PMSM: A simulation study
PublicationPredictive current control algorithms for permanent magnet synchronous (PMSM) drives rely on an assumption that within short intervals motor currents can be approximated with linear functions. This approximation may result either from discretizing the motor model or from simplifications applied to the continuous-time model. As the linear current approximation has been recognized as inaccurate in case when the drive operates with...
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Stability Analysis of Shunt Active Power Filter with Predictive Closed-Loop Control of Supply Current
PublicationThis paper presents a shunt active power filter connected to the grid via an LCL coupling circuit with implemented closed‐loop control. The proposed control system allows selective harmonic currents compensation up to the 50th harmonic with the utilization of a model‐based predictive current controller. As the system is fully predictive, it provides high effectiveness of the harmonic reduction, which is proved by waveforms achieved...
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Oxylipin profiling for clinical research: Current status and future perspectives
PublicationOxylipins are potent lipid mediators with increasing interest in clinical research. They are usually measured in systemic circulation and can provide a wealth of information regarding key biological processes such as inflammation, vascular tone, or blood coagulation. Although procedures still require harmonization to generate comparable oxylipin datasets, performing comprehensive profiling of circulating oxylipins in large studies...
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Complete Mesogastric Excisions Involving Anatomically Based Concepts and Embryological-Based Surgeries: Current Knowledge and Future Challenges
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Thermal and Electrodynamic Risk of Residual Current Devices in the Case of Back-Up Protection by Overcurrent Circuit Breakers
PublicationResidual current operated circuit breakers without integral overcurrent protection should be back-up protected. As back-up protection devices, overcurrent circuit breakers are used. The maximum let-through energy and let-through current of the overcurrent devices were evaluated under laboratory conditions. The thermal and electrodynamic risk of residual current devices was analyzed.
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Case Study of Stray Current Corrosion of Tall Ship Mast
PublicationNowadays, in the present technical civilization there are numerous complex technical systems that may generate various hazards. Large transport units like ships can be considered as the most dangerous systems. Therefore, it is important to eliminate all possible hazards, especially for ship crewmembers. Destruction of ship structural components caused by vast corrosion is one of these hazards. Usually, its activity leads to a decrease...
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Modification of current-voltage characteristics of planar organic systems by nm-thick interlayer
PublicationEffect of nm-thick interlayer of copper phthalocyanine (CuPc) or perylene dye (MePTCDI) on current-voltage characteristics of planar organic systems is discussed in the work. The MePTCDI layer strongly limits injection of holes from ITO into CuPc, while CuPc limits injection of electrons from ITO into MePTCDI. In the systems with CuPc/MePTCDI heterojunction an explicit photovoltaic effect occurs.
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Novel condition monitoring of induction motor bearings via motor current signature analysis
PublicationThe paper authors are researching the assessment of bearing conditions in induction motors. The methods developed by the authors are based on measurements and analysis of the motor supply current, which is particularly attractive in the absence of access to the engine. The article provides an overview of selected methods of induction motor bearings diagnostic based on Motor Current Signature Analysis (MCSA). However, there is no...
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Source-related Wavefields in Fluids and Dielectrics: A new way of Thinking about Medium Dynamics
PublicationAcoustic and electromagnetic wave phenomena may seem to have a proper formal representation in field theory dating from the 19th century, founded on the mathematics of complex functions. This paper shows, however, that when replacing the classical spectrum-domain approach related to the assumption of harmonic timeform of signals, with a time-domain approach imposingnorestrictionastotheclassoftimeevolutionofsourceandfieldsignals,...
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A new open-source software developed for numerical simulations usingdiscrete modeling methods
PublicationThe purpose of this work is to present the development of an open-source software based on a discrete description of matter applied to study the behavior of geomaterials. This software uses Object Oriented Programming techniques, and its methodology design uses three different methods, which are the Discrete Element Method (DEM) [F. Donzé, S.A. Magnier, Formulation of a three-dimensional numerical model of brittle behavior, Geophys....
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Current Status, Barriers and Development Perspectives for Circular Bioeconomy in Polish South Baltic Area
PublicationThe following article presents the current legal situation in Poland as well as in the European Union. Data on biomass production in the Polish South Baltic area were analyzed, along with an indication of the key sectors for the development of bioeconomy. Presentation of the current state of biomass management was made and areas necessary for development were indicated to facilitate the sustainable management of biomass and waste...
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Voltage fluctuations on the main switchgear of the industrial power system supplying the rolling mill motors_part_2
Open Research DataThe dataset presents the voltage waveforms on the bus bars of the main switchgear of the industrial power network for the supply of rolling mills. The data was recorded during an experiment whose purpose was to determine a level of short-term and long-term flicker caused by voltage fluctuations. In the virtual application of flickermeter, a hardware...
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Implementation of high-precision computation capabilities into the open-source dynamic simulation framework YADE
PublicationThis paper deals with the implementation of arbitrary precision calculations into the open-source discrete element framework YADE published under the GPL-2+ free software license. This new capability paves the way for the simulation framework to be used in many new fields such as quantum mechanics. The implementation details and associated gains in the accuracy of the results are discussed. Besides the "standard" double (64 bits)...
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Synthesized light source for optical coherence tomography
PublicationW artykule omówiono wpływ parametrów źródła promieniowania optycznego na właściwości systemu OCT. Szczególną uwagę zwrócono na źródła syntezowane. Omówiono charakterystykę źródła zbudowanego z dwóch różnych diod SLD. Przedstawiono wyniki pomiarów, które wskazują na możliwości znacznego polepszenia czułości i rozdzielczości systemu OCT wykorzystującego takie źródło.
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Documentation generator application for VHDL source codes
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A plug-in to Eclipse for VHDL source codes: functionalities
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Documentation generator application for MatLab source codes
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Open Source in Development: Enabling Business and Services
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Baltic cyanobacteria – a source of biologically active compounds
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MARITIME LASER SCANNING AS THE SOURCE FOR SPATIAL DATA
PublicationThe rapid development of scanning technology, especially mobile scanning, gives the possibility to collect spatial data coming from maritime measurement platforms and autonomous manned or unmanned vehicles. Presented solution is derived from the mobile scanning. However we should keep in mind that the specificity of laser scanning at sea and processing collected data should be in the form acceptable in Geographical Information...
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Neutrophil extracellular traps as the main source of eDNA
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A digital cartographic source for numerical models in hydrology
PublicationAutorzy prowadzą analizę wykorzystania i przydatności cyfrowych danych kartograficznych w rozwiązywaniu przestrzennych zagadnień hydrologicznych. Szczególne znaczenie dla prowadzonych analiz mają DTM i DEM. Są one źródłem bezpośrednich wielkości wejściowych modelu hydrologicznego i dodatkowo pozwalają na szersze możliwości prezentacji otrzymanego rozwiązania.
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On numerical calculation of acoustic field of plane source.
PublicationSkładowe harmoniczne wiązki akustycznej zostały obliczone na podstawie reprezentacji w postaci całek według teorii reprezentacji. Zastosowano nowe metody do obliczania całek od funkcji szybko oscylacyjnych.
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Thermal lenses caused by any acoustic source.
PublicationNieliniowe straty energii fali akustycznej doprowadzają do powstania obszarów ogrzanych, to znaczy obszarów o innej prędkości fali akustycznej niż pozostała przestrzeń. Soczewki termiczne wywoływane przez propagację fal akustycznych okresowych i nieokresowych są rozpatrywane. Przedstawiono ilustrację obliczeń numerycznych.
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Distribution of heat generated by a local heat source
PublicationW pracy przedstawiono analizę rozpływu ciepła wygenerowanego przez lokalne źródło umieszczone w płycie, po której przepływa warstwa wody.
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СИЛОВОЙ ПРЕОБРАЗОВАТЕЛЬ С АКТИВНЫМ ПОДАВЛЕНИЕМ ВЫСШИХ ГАРМОНИК ДЛЯ СИСТЕМ ЭЛЕКТРОСНАБЖЕНИЯ ЛЕТАТЕЛЬНЫХ АППАРАТОВ (Power converter with active suppression of higher harmonics for aircraft power supply systems)
PublicationПредставлены два алгоритма активной фильтрации для силового преобразователя с активным подавлением высших гармоник. Первый алгоритм основан на дискретном преобразовании Фурье: посредством синтезированной системы управления инвертированные измеренные высшие гармоники напряжения поступают на вход инвертора. Второй метод управления основан на алгоритме с использованием принципов самообучения, что значительно снижает потребность в...