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Search results for: dc micro grid
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Edu Inspiracje WZiE: Czy mikrokwalifikacje i cyfrowe odznaki zmienią oblicze edukacji?
PublicationMikrokwalifikacje nazywane również mikropoświadczeniami (micro- -credentials), mówiąc prostymi słowami, są cyfrowymi certyfikatami potwierdzającymi uzyskanie umiejętności, wiedzy lub kompetencji. To dowody ukończenia mniejszych (niż określają np. dyplomy uniwersyteckie) form edukacyjnych takich jak kursy e-learningowe, warsztaty lub szkolenia. Pozwalają też szybko pokazać to, co umiemy, i przedstawić w postaci atrakcyjnego cyfrowego...
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On various modelling approaches to real-time visualisation of blood flow
PublicationThis paper reviews various modelling approaches to real-time visualisation of blood flow. These include classic, macroscale approach based on the momentum conservation equation together with a proper constitutive equation. Moreover, modern micro- and mesoscale approaches, such as molecular dynamics and dissipative particle dynamics, are discussed. Advantages and disadvantages of the discussed methods are highlighted with particular...
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Analysis and Evaluation of the Working Cycle of the Diesel Engine
PublicationThe paper presents a proposal to apply a quantitative evaluation of the diesel engine with regard to the phenomena occurring during of a working cycle. The proposed procedure when analyzing test results from diesel engine is an attempt to transfer an engine activity evaluation methods in the operational time scale (exploit time), eg. in hours, to the micro-scale (dynamic time) relating only to the execution time of one (several)...
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A Set of Low-power Microcontroller-based Modules Used for Testing of Small Energy Measurement Methods
PublicationEstimation of energy consumption of low-power devices is not widely discussed in the scientific literature, but this topic is getting more and more popular. Evaluation process of newly developed methods and instrumentation requires carefull treatment. In order to fulfill this niche, the set of micro-power microcontroller based devices was proposed. The devices represent typical energy consuption profiles and allow experimental verification...
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Comparative modeling of shear localization in granular bodies with FEM and DEM
PublicationThe intention of the paper is to compare the calculations of shear zones in granular bodies using two different approaches: a continuum and a discrete one. In the first case, the FEM based on a micro-polar hypoplastic constitutive law was used. In the second case, the DEM was taken advantage of, where contact moments were taken into account to model grain roughness. The comparative calculations were performed for a passive case...
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A universal algorithm of space vector pulse width modulation for three-level three- and multi-phase NPC inverters with DC-link voltage balancing
ProjectsProject realized in Department of Electric Drives and Energy Conversion according to UMO-2021/41/N/ST7/01968 agreement from 2021-11-26
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Single-Phase 15-Level Switched-Capacitor Boost Multilevel Inverter Topology for Renewable Energy Applications
PublicationGalvanic isolation is a vital part of a grid-connected solar PV system. With the growth of multilevel inverters for grid-connected applications, the multilevel inverters having isolation are not sufficiently discussed in the literature. In this paper, a 15-level isolated multilevel inverter topology requiring only thirteen switches is proposed. The envisaged configuration includes two cells, designated as upper and lower cells....
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STABILITY OF THE INNER SLOPE OF THE POLISH DREDGDIKES RESEARCH DIKE AT STATIONARY FLOW
PublicationFor long duration of the flood the water table can appear on the slope with a problem of out-wash in the case of sand type dike. If the dike corps is covered with less permeable layer some additional push-off forces and shearing can rise in the cover. In both cases the micro stability of the inner slope should be considered at normative high water for homogeneous sand type dike or sand type dike with less permeable covers. The...
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Size effect at aggregate level in microCT scans and DEM simulation – Splitting tensile test of concrete
PublicationThe paper describes an experimental and numerical study of size effect on concrete cylindrical specimens in splitting tensile test. Own experimental campaign was performed on specimens with 5 various diameters from D = 74, 105, 150, 192 and 250 mm with hardboard loading strips (distributed load according to standard methods) scaled proportionally to the specimen diameter. The crack opening-control system was applied to obtain the...
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The new concept of capillary forces aided evaporator for application in domestic organic rankine cycle
PublicationThis paper presents studies on the possibility of applying capillary forces induced in the porous structure to a modern design of evaporator. The potential application of such heat exchanger is for example an evaporator of the domestic micro combined heat and power (CHP) unit. One of the problems in the micro-CHP is excessive demand for pumping power. The proposed design helps in overcoming that issue. In the evaporator outlined...
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Technologia biomems - przegląd zastosowań
PublicationThe paper reviews the issues related to technology, MEMS (Micro-Electro Systems-Mechanical) in the context of applications in biotechnology and biomedical systems. Systems of this type, with applications in biology and medicine, have the name of our common BioMEMS systems. This pertains to a wide range of technology BioMEMS. The aim of this study is to determine future medical MEMS microphones with particular emphasis on their...
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Investigations of size effect in concrete at aggregate level - experiments and calculations results using discrete element method
PublicationSize effect is a fundamental phenomenon in concrete. It is characterised by decreasing strength and increasing brittleness of concrete with increasing size. The thesis includes experimental and theoretical elements. The main goal of the thesis were investigations of a size effect at the aggregate level by taking fracture into account with the discrete element method (DEM) for various failure modes. Comprehensive experiments on...
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Bezpieczeństwo elektryczne przy urządzeniach przytorowych niskiego napięcia zelektryfikowanych linii kolejowych
PublicationW referacie przedstawiono zasady zasilania urządzeń pomocniczych niskiego napięcia, obsługujących zelektryfikowany szlak kolejowy. Ze względu na oddziaływanie sieci trakcyjnej DC 3 kV (zagrożenie porażeniem, prądami błądzącymi), szczególnej uwagi wymaga wybór układu sieci nn i środków ochrony przeciwporażeniowej, a także konfiguracja instalacji uziemiających. Za podstawę przyjęto system trakcji o grupowym uszynieniu otwartym, które...
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Solutions of inverter systems in Shore-to-Ship Power supply systems
PublicationThe article presents a clearly formulated need for installing S2SP (Shore to Ship Power) systems, in particular Medium Voltage (MV) systems, along with certain solutions of modern inverter systems used in those systems. Requirements and basic configurations of S2SP systems are discussed, focusing in particular on capabilities of the S2SP system with DC distribution busbar. Moreover, on the background of the executing assumptions...
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Synthesis and Testing of BCZY/LNZ Mixed Proton–electron Conducting Composites for Fuel Cell Applications
PublicationA composite of BaCe0.6Zr0.2Y0.2O3–δ and Li2O:NiO:ZnO was investigated for fuel cell applications. The composite was successfully synthesized and its phase stability was confirmed at temperatures up to 900 °C. The influence of sintering and pressing aids on density was also investigated. Electrical properties were measured. DC electrical conductivity was about 8•10-4 S/m at 845 K. Open circuit voltage measurements in wet hydrogen...
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Modular multipulse voltage source inverters with integrating coupled reactors
PublicationA novel approach to the voltage source inverters (VSI) construction is presented in the paper. The invented inverter structures allow to operate several DC/AC converters in parallel resulting in lower voltage distortions at extremely low switching frequency. The research presented in the paper describes such a parallel operation of the VSI’s which is possible thanks to the use of coupled inductors. The eighteen-pulse and twenty-four-pulse...
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Investigation of magnetic order in a new intermetallic compound Nd2PtGe3
PublicationIn the present study we report a successful synthesis of the new intermetallic compound Nd2PtGe3 by an arc-melting method. The powder X-ray diffraction analysis indicates that this compound crystallizes in an disordered variant of the AlB2-type structure (space group P6/mmm, no. 191) with lattice parameters a = 4.2455 Å and c = 4. 1933 Å. The compound exhibits a cluster-glass transition below Tf = 2.9 K, characterized through ac...
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Testing HIADAC high impedance analyzer in cooperation with Road and Bridge Research Institute on polyvinyl coating using 2-wire probe sample 1
Open Research DataThe dataset presents impedance spectrum of polyvinyl coating (code-name PW_2_2_1) sample 1. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (0.1 Hz – 100 kHz) was selected in order to test the whole measureement...
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Testing HIADAC high impedance analyzer in cooperation with Road and Bridge Research Institute on polyvinyl coating using 2-wire probe sample 2
Open Research DataThe dataset presents impedance spectrum of polyvinyl coating (code-name PW_2_2_1) sample 2. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (0.1 Hz – 100 kHz) was selected in order to test the whole measureement...
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Testing HIADAC high impedance analyzer in cooperation with Road and Bridge Research Institute on nano-nickel based coating using 2-wire probe sample 2
Open Research DataThe dataset presents impedance spectrum of nano-nickel based coating sample 2. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (0.1 Hz – 100 kHz) was selected in order to test the whole measureement range of...
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Testing high impedance analyzer in the field on high-voltage line pylon cell 1 exposition 2
Open Research DataThe dataset presents impedance spectrum of anticorrosion coating on high-voltage line pylon presented in the figure below. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The dataset contains comparative measurements with Atlas-Sollich ATLAS98HI analyser....
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Testing high impedance analyzer in the field on high-voltage line pylon cell 1 exposition 1
Open Research DataThe dataset presents impedance spectrum of anticorrosion coating on high-voltage line pylon presented in the figure below. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The dataset contains comparative measurements with Atlas-Sollich ATLAS98HI analyser....
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Testing HIADAC high impedance analyzer in cooperation with Road and Bridge Research Institute on nano-nickel based coating using 2-wire probe sample 1
Open Research DataThe dataset presents impedance spectrum of nano-nickel based coating sample 1. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (0.1 Hz – 100 kHz) was selected in order to test the whole measureement range of...
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Testing high impedance analyzer in the field on high-voltage line pylon cell 2 exposition 1
Open Research DataThe dataset presents impedance spectrum of anticorrosion coating on high-voltage line pylon presented in the figure below. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The dataset contains comparative measurements with Atlas-Sollich ATLAS98HI analyser....
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Investigation of plasmon resonance in a silver nanoparticles
Open Research DataSilver nanostructures were prepared on borosilicate glass (Corning 1737F) substrates. Thin Ag films (1–9 nm thickness) were deposited using a table-top dc magnetron sputtering coater (EM SCD 500, Leica) in pure Ar plasma (argon, Air Products 99.999%). The Ag target was of 99.99% purity, the rate of layer deposition was about 0.4 nm·s−1, and the incident...
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SEM images of tge gold nanostructures on silicon
Open Research DataAu nanostructures were prepared on Si(111) as a substrate. The substrates (1 × 1 cm2 of area) were cleaned with acetylacetone and then rinsed in ethanol. Thin Au films (with thicknesses in a range of 1.7–5.0 nm) were deposited using a table-top dc magnetron sputtering coater (EM SCD 500, Leica) under pure Ar plasma conditions (Argon, Air Products 99.999%)....
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Czynniki wzrostu zatrudnienia w mikro przedsiębiorstwach – czy chcieć znaczy móc?
PublicationDotychczasowe badania nad wzrostem małych i średnich przedsiębiorstw, prowadzone od wielu lat zarówno na świecie jak i w Polsce nie przyniosły odpowiedzi na pytanie jakie czynniki na to zjawisko wpływają. W artykule przedstawiono pokrótce podejścia badawcze wykorzystywane w badaniu czynników wzrostu. W oparciu o przeprowadzone w 2009 i 2012 roku badania panelowe w Województwie Pomorskim, przeanalizowano wpływ czynników związanych...
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The influence of azide and imidazole on the properties of Mn- and Cd-based networks: conductivity and nonlinear phenomena
PublicationWe report a study on a family of four new Mn- and Cd-azide-imidazolate-based compounds with various crystal architectures. Notably, three of these compounds display noncentrosymmetric crystal arrangements at room temperature, a rare phenomenon in hybrid organic–inorganic materials. Both nonlinear optical (NLO) and electrical phenomena in these compounds are observed. The NLO processes include second and third harmonic generation,...
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The adaptive backstepping control of PMSM supplied by current source inverter for the field weakening region
PublicationThe sensorless control system of permanent magnet synchronous motor PMSM supplied by current source inverter for field weakening operation is presented in this paper. The adaptive backstepping control system and the backstepping speed observer are presented. The control system is based on multi-scalar variables. The control variables are: dc-link voltage and the output current vector pulsation. The control system was named voltage...
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Micro-Raman spectroscopy in the studies of multiphase separated polyurethanes. [online] W: [Proc.] UTECH Europe 2003 . The International Polyurethane Industry Conference and Exhibition. 25/26/27 March 2003, The Hague, Netherlands. London: Crain Communications Ltd. Dostępny w World Wide Web: http://UTECH-2003.com + wydruk.**2003 [s. 123-130 bibliogr. 41 poz.]Mikro-Ramanowska spektroskopia w badaniach poliuretanów wykazujących separację wielofazową.
PublicationPrzedmiotem badań były trzy próbki poliuretanowe o zawartości 30% segmentówsztywnych otrzymanych z politlenku propylenu, diizocyjanianu difenylometanui butanodiolu. Próbki te wykazują morfologię wielofazową, w której można wy-różnić globule i sferolity rozproszone w matrycy polimerowej.Za pomocą spek-troskopii mikro-Ramana przeprowadzono mikroanalizę chemiczną wszystkich ele-mentów morfologicznych. Stwierdzono odmienny skład...
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Zespół Systemów Mikroelektronicznych
Research Teams* projektowania I optymalizacji układów i systemów mikroelektronicznych * zaawansowane metody projektowania i optymalizacji analogowych filtrów aktywnych * programowanie układów scalonych (FPGA, CPLD, SPLD, FPAA) * układy specjalizowane ASIC * synteza systemów o małym poborze mocy * projektowanie topografii układów i zagadnień kompatybilności elektromagnetycznej * modelowania przyrządów półprzewodnikowych * modelowania właściwości...
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The Finite Elements Method application to assesment the impact of turbulence generated by wind turbines on their lacation inclose proximity of overhead high voltage power transmissionlines
PublicationThe paper presents selected aspects of construction of wind turbines location concerning aerodynamic impact on power lines. Reaserch is based on the source data concerning the aerodynamic impact of a wind farm consisting of 8 turbines and 400 kV power line, an analysis of the possibility of wind farm locating in the immediate vicinity of the line was carried out. There are serious problems with locating higher capacity wind farms...
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Face Recognition: Shape versus Texture
PublicationThis paper describes experiments related to the application of well-known techniques of the texture feature extraction (Local Binary Patterns and Gabor filtering) to the problem of automatic face verification. Results of the tests show that simple image normalization strategy based on the eye center detection and a regular grid of fiducial points outperforms the more complicated approach, employing active models that are able to...
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Numerical Modelling of Shear Localization in Granular Bodies using MPM and Non-local Hypoplasticity
PublicationThe paper deals with modelling of shear localization in granular bodies by means of an enhanced hypoplastic constitutive model and material point method (MPM). The calculations were carried out for plane strain compression of non-cohesive sand. In order to properly capture the width and inclination of shear zones, the constitutive model was enriched by a characteristic length of micro-structure by means of a non-local theory....
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Ochrona przeciwporażeniowa w urządzeniach przytorowych niskiego napięcia zelektryfikowanych linii kolejowych
PublicationW artykule przedstawiono zasady ochrony przeciwporażeniowej w instalacjach urządzeń pomocniczych niskiego napięcia, obsługujących zelektryfikowany szlak kolejowy. Ze względu na oddziaływanie sieci trakcyjnej DC 3 kV (zagrożenie porażeniem, prądami błądzącymi), szczególnej uwagi wymaga wybór układu sieci niskiego napięcia i środków ochrony przeciwporażeniowej, a także konfiguracja instalacji uziemiających. Rozważono system trakcji...
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Redukcja liczby przełączeń tranzystorów w falowniku kaskadowym z wektorową modulacją szerokości impulsów
PublicationW artykule zaprezentowano metody ograniczania liczby przełączeń tranzystorów wybranych mostków kaskadowego falownika napięcia z wektorową modulacją szerokości impulsów. Zaproponowane rozwiązanie umożliwi sterowanie temperaturą poszczególnych mostków H przekształtnika, w którym ten sam strumień powietrza wykorzystano do chłodzenia kilku mostków H. Zmiana liczby przełączanych tranzystorów nie wpływa na dokładność...
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Ribosomal intergenic spacer analysis as a tool for monitoring methanogenic archaea changes in an anaerobic digester
PublicationThe applicability of a newly-designed PCR primer pair in examination of methanogenic Archaea in a digester treating plant biomass was evaluated by Ribosmal Intergenic Spacer Analysis (RISA). To find a suitable approach, three variants of RISA were tested: (1) standard, polyacrylamide gel-based, (2) automated, utilized capillary electrophoresis (GA-ARISA), and (3) automated microfluidics-based (MF-ARISA). All three techniques yielded...
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Voltage variations and their reduction in a rural low-voltage network with PV sources of energy
PublicationRenewable sources of energy (RES), especially photovoltaic (PV) micro-sources, are very popular in many countries. This way of clean power production is applied on a wide scale in Poland as well. The Polish legal regulations and tariffs specify that every prosumer in a low-voltage network may feed this network with a power not higher than the maximum declared consumed power. In power networks with RES, the voltage level changes...
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Numerical analysis of high temperature minichannel heat exchanger for recuperative microturbine system
PublicationConsidering the development of energy sector, distributed small-scale power generation, e.g., gas micro-CHP, is attracting considerable interest. In such installations, the heat exchanger is one of the key components possessing a significant influence on overall performance. Most studies concentrate on units operating below 900C, which do not fulfil the requirements of gas micro-CHP. Therefore, there remains a challenge to design...
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Elektro-magnetyczna metoda badania procesu degradacji stali austenitycznych
PublicationBadano próbki ze stali A304 oraz A347 po eksploatacji oraz próbki poddane deformacji plastycznej. Przyjęto założenie, że degradacja prowadzi do wzrostu zawartości fazy ferrytycznej w tych stalach, co może być wykorzystane do oceny stopnia degradacji. Artykuł prezentuje wyniki wstępnych badań nad możliwością wykrycia relatywnie niewielkich koncentracji fazy ferrytycznej. Próbki w początkowym stadium procesu degradacji (wycięte z...
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Improvement of microstructure and mechanical properties of high dense sic ceramics manufactured by high-speed hot pressing
PublicationNon-oxide ceramics possess high physical-mechanical properties, corrosion and radiation resistance, which can be used as a protective materials for radioactive wastes disposal. The aim of the present study was the manufacturing of high density SiC ceramics with advanced physical and mechanical parameters. The high performance on the properties of produced ceramics was determined by the dense and monolithic structure. The densified...
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THE USE OF THE Ti-13Zr-13Nb ALLOY POWDER FOR MANUFACTURING OF PROSTHETIC PARTS BY SELECTIVE LASER MELTING
PublicationThe 3D printing is a manufacturing technique belonging to the additive methods able to prepare the designed parts for various purposes. The present reasearch was aimed to fabricate the prosthetic foundations and bridges made of the new Ti-13Zr-13Nb alloy by the selective laser melting (SLM) of a metal powder. The scanning electron examinations and micro scanning tomography were used to investigate the surface quality and intrinsic...
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Residual current protective device for circuits of distorted earth fault currents – concept, construction and testing
PublicationThis dissertation presents behavioral and performance verification and analysis of residual current devices (RCDs), as well as a proposal for the construction of a new RCD protection. The state of the art focuses over pre-existing design of the RCD and its behavior and response to the circuits with distorted (non-sinusoidal) earth fault currents. The study highlights the loopholes of the existing design and depicts the problem...
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The effects of gas exposure on the graphene/AlGaN/GaN heterostructure under UV irradiation
PublicationThis work demonstrates a graphene/AlGaN/GaN sensing device with two-dimensional electron gas (2DEG) toward nitrogen dioxide (NO2), tetrahydrofuran, and acetone detection under UV light irradiation. We propose combining measurements of the DC characteristics with a fluctuation-enhanced sensing method to provide insight into the gas detection mechanisms in the synergistic structure of highly stable GaN and gas-sensitive graphene....
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New Architecture of Solid-State High-Voltage Pulse Generators
PublicationThe application of the nanosecond pulsed electric field (nsPEF) for biomedical treatments has gained more interest in recent decades due to the development of pulsed power technologies which provides the ability to control the electric field dose applied during tests. In this context, the proposed paper describes a new architecture of solid-state high-voltage pulse generators (SSHVPG) designed to generate fully customised sequences...
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Microwave Characterization of Dielectric Sheets in a Plano-Concave Fabry-Perot Open Resonator
PublicationDespite its long history, a double-concave (DC) Fabry-Perot open resonator (FPOR) has recently gained popularity in the characterization of dielectrics in the 20–110 GHz range, mainly due to such novel accomplishments as full automation of the measurement process and the development of even ore accurate and computationally efficient electromagnetic model. However, it has been discovered that such a DC resonator suffers from unwanted...
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Syntactic modular decomposition of large ontologies with relational database
PublicationSupport for modularity allows complex ontologies to be separated into smaller pieces (modules) that are easier to maintain and compute. Instead of considering the entire complex ontology, users may benefit more by starting from a problem-specific set of concepts (signature of problem) from the ontology and exploring its surrounding logical modules. Additionally, an ontology modularization mechanism allows for the splitting up of...
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Ancillary services to grids provided with distributed generation
PublicationThe paper introduces system for utilization of the customer-side generated energy. Additionally system can secure some ancillary services to grids. Those services include: current active filtering, load voltage stabilization and in case of grid voltage faults - uninterruptible load supplying (possible with energy storage device). Presented experimental results confirm flexibility of this arrangement in processes of power delivery...
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Fluctuation-enhanced sensing of organic solvent vapors mixture by machine learning
Open Research DataThe data set consists of exemplary results of the product of voltage noise power spectral density S(f) multiplied by frequency f and normalized to squared DC voltage U^2 recorded in the graphene back-gated Field Effect Transistor under UV light assistance (275 nm) in the selected ambient atmospheres (Figure 3) and the results of gas detection by SVM...
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Simulation of perovskite-based CuI/CH3NH3PbI3/TiO2 solar cell performance
Open Research DataThe presented data set is part of the theoretical research on novel thin-layer lead-halide perovskite solar cells with different inorganic transparent conductive oxides used as charge transport layers. In this study CuI/CH3NH3PbI3/TiO2 model structure (Model 1) was investigated by the use of the SCAPS-1D simulation method (https://scaps.elis.ugent.be/).