Filters
total: 1648
filtered: 957
-
Catalog
- Publications 957 available results
- Journals 9 available results
- Conferences 1 available results
- Publishing Houses 1 available results
- People 44 available results
- Inventions 2 available results
- Projects 13 available results
- Laboratories 3 available results
- Research Teams 1 available results
- Research Equipment 3 available results
- e-Learning Courses 178 available results
- Events 16 available results
- Open Research Data 420 available results
Chosen catalog filters
Search results for: VSV-PWM
-
A XAS study of a highly diluted Pt electrocatalyst operating in PEM fuel cells
PublicationWe present an X-ray absorption spectroscopy (XAS) study of a low Pt content catalyst layer(Pt loading 0.1 mg c2) operating at the cathode of a proton exchange membrane fuel cell(PEMFC). This catalyst is based on the use of a mesoporous inorganic matrix as a support forthe catalyst Pt nanoparticles. Due to the high Pt dilution, in situ measurements of itsstructural properties by XAS are challenging and suitable experimental strategies...
-
The Possibility of Phase Change Materials (PCM) Usage to Increase Efficiency of the Photovoltaic Modules
PublicationSolar energy is widely available, free and inexhaustible. Furthermore this source of energy is the most friendly to the environment. For direct conversion of solar energy into useful forms like of electricity and thermal energy, respectively photovoltaic cells and solar collectors are being used. Forecast indicate that the first one solution will soon have a significant part in meeting the global energy demand. Therefore it is...
-
Reliability assessment of truss towers using Monte Carlo Method, PEM and RSM
PublicationThe paper discusses the reliability assessment of simple random truss structures using three different probabilistic methodologies: the Monte Carlo method, the Point Estimate Method and the Response Surface Method. A benchmark truss structure example is analyzed. A set of numerical calculations of critical load is performed and the results are taken as the basis of advanced probabilistic calculations. Using the samples, numerical...
-
Reliability assessment of truss towers using Monte Carlo Method, PEM and RSM
PublicationThe paper discusses reliability assessment of simple random truss structures using three different probabilistic methodologies: the Monte Carlo Method (MCM), the Point Estimate Method (PEM) and the Response Surface Method (RSM). A benchmark truss structure and a simplified full–size engineering tower are both analyzed. A set of ultimate load numerical calculations is performed and the results are taken as the basis of advanced...
-
Aaliza zjawisk dynamicznych w komorze cylindrowej pompy pwk o zmiennej wydajności
Publicationopisano budowę i zasadę działania mechanizmu zmiany wydajności pompy wielotłoczkowej osiowej pwkz sterowanej krzywkowo. wyjaśniono przyczyny powstawania zjawisk dynamicznych w komorach roboczych towarzyszących przejściu komory z fazy tłoczenia w fazę ssania. dla opisania tych zjawisk przeprowadzono teoretyczną analizę zmian ciśnienia występujących w pojedynczej komorze roboczej pompy, powstających w wyniku dodatniego przekrycia...
-
Thermal stabilization and permanent deformation resistance of LWA/PCM-modified asphalt road surfaces
PublicationThis paper presents the results of attempts at reducing the problem of solar overheating of asphalt road pavement surfaces, resulting in weakening and accelerated destruction of the aforementioned structures. To protect pavement surfaces against periodic overheating, standard asphalt mixture AC 16 W 35/50, used for binder course, has been modified by replacing one of the aggregate fractions from the mineral mixture with lightweight...
-
Impedance Measurement and Selection of Electrochemical Equivalent Circuit of a Working PEM Fuel Cell Cathode
PublicationThe dynamic impedance analysis of direct methanolfuel cell (DMFC) cathode supplied with pure oxygen is pre-sented. Presented results were obtained during dynamic chang-es of the current density in working fuel cell. Investigation ofthe occurring processes at cathode was carried with dynamicelectrochemical impedance spectroscopy (DEIS). A discussionwas conducted based on the determined correlation parameterχ2. It was shown that...
-
Multi-nodal PWR reactor model — Methodology proposition for power distribution coefficients calculation
PublicationIn the paper the multi-nodal Pressurized Water Reactor (PWR) model called Mann’s model is presented. This models is used for modelling purposes of the heat transfer from fuel to coolant in reactor core. The authors expand widely used in literature approach by defining additional coefficients for the heat transfer model. These parameters approximate the power generation distribution in the PWR reactor core according to the to the...
-
Implementation of the FOPID Algorithm in the PLC Controller - PWR Thermal Power Control Case Study
PublicationIn the paper authors describe proposition of design and verification procedures of the discrete Fractional Order PID (FOPID) algorithm for control of the Pressurized Water Reactor (PWR) thermal power near its nominal operating point. The FOPID algorithm synthesis consists of: off-line optimal tunning of its parameters in continuous time-domain with LQ (Linear Quadratic) performance index and simplified models of nuclear reactor...
-
Multi-pulse VSC arrangements with coupled reactors
PublicationThis paper presents a novel approach to the multipulse VSC (Voltage Source Converter) arrangements based on several conventional inverter modules connected in parallel by using coupled reactors. This solution reduces the THD of the output voltage, despite the low switching frequency of transistors. The advantage of the proposed solution is also a relatively small rated power of the reactors. Proposed new arrangements for different...
-
Experimental investigations of DAC Systems operating in VAV Control mode
PublicationPraca przedstawia techniczne aspekty wykorzystania ciepła sieciowego w bezsprężarkowych, adsorpcyjnych systemach klimatyzacyjnych na przykładzie zrealizowanej instalacji w EC Gdansk.Zaprezentowano również stanowisko oraz wyniki badań eksperymentalnych doyczących wpływu zmian parametrów przepływowych powietrza wilgotnego na efektywność pracy regeneratorów ciepła.
-
Surfaces formability of PM parts by lapping.
PublicationPrzedstawiono wyniki badań docierania elementów spiekanych. Określono wpływ podstawowych warunków obróbki na jakość powierzchni płaskich oraz omówiono sposób wymuszonej aktywizacji powierzchni docieraka metalowego ścierniwem.
-
Opinion about causes of framing of Kingston chest (box cooler) damage, on PSV vessel VS4411 DF-PSV (B-855)
PublicationThe subject of analysis is a damage of welded connection of box cooler framing segments, made as separate bars 50mm thickness, connected by the welds in corners. Studies of documents delivered by Customer shows cracks on the fusion of filet welds and twisting of box cooler frame. The subject of analysis is a damage of welded connection of box cooler framing segments, made as separate bars 50mm thickness, connected by the welds...
-
Steady-state characteristics and dynamic response of the PEM fuel cell to unit step change of load
PublicationPodano opis układu zasilania opartego na dwóch ogniwach paliwowych typu PEM o łącznej mocy 2.4 kW. Zaprezentowano wybrane charakterystyki statyczne i dynamiczne układu.
-
Performance of the PEM fuel cell module. Part 2. Effect of excess ratio and stack temperature
PublicationThe paper describes a fuel cell based system performance under different thermal conditions. The system could be fed with bottled hydrogen or with very high purity hydrogen obtained from reforming of methanol. The system is based on two fuel cell units (1.2 kW each, produced by Ballard Power Systems Inc. and called Nexa), DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and...
-
Single-phase, Five-level Inverter with SPWM-Based Neutral Point Voltage Balancing Scheme
PublicationMultilevel inverter topologies provide several advantages over two-level inverter configuration. These benefits are the reason for the growing interest in multilevel topologies among research society. One of the most popular topological concepts (diode and active switch clamping) requires neutral-point potential balancing due to series-connected capacitor banks across the input dc link in such derived inverter configurations. This...
-
VUV irradiation studies of plasmid DNA in aqueous solution
PublicationInteractions of VUV light and DNA samples in aqueous solutions are reported. The damage induced by such radiation is quantified by monitoring both loss of supercoiled DNA and formation of single and double strand breaks using agarose gel electrophoresis. Irradiations were performed using synchrotron VUV photons of 130, 150, 170 and 190 nm. VUV irradiation experiments revealed enhanced damage upon irradiation with 170 nm photons...
-
Badanie eksperymentalne pompy wielotłoczkowej osiowej PWK 27 firmy Hydrotor w niskich temperaturach otoczenia
PublicationW artykule przedstawiono stanowisko oraz badania pompy wielotłoczkowej osiowej PWK 27 w niskich temperaturach otoczenia. Celem badań pompy PWK27 było określenie obszaru parametrów prawidłowego rozruchu w warunkach szoku termicznego oraz analiza zjawisk występujących podczas rozruchu pomp wielotłoczkowych osiowych.
-
Structural change of carbon supported Pt nanocatalyst subjected to a step-like potential cycling in PEM FC
PublicationIn this paper we present detailed X-ray absorption fine structure (XAFS), X-ray diffraction (XRD) and transmission electron microscopy (TEM) investigations of the changes in the local geometric and electronic structure of Pt nanoparticles used as a cathode catalyst in proton exchange membrane fuel cell (PEMFC), working under controlled potential cycling conditions.
-
Experimental and numerical investigation on shell and coil storage unit with biodegradable PCM for modular thermal battery applications
PublicationThermal energy storage (TES) in automotive applications is currently growing in importance. TES can visibly reduce primary energy consumptions, decrease CO2 emission, and improve thermal comfort in electric as well as hybrid vehicles. However, to meet the new ambitious target (15% reduction of CO2 emissions in the new cars until 2025) it is required to use plug-in electric vehicles. For this reason, this paper focuses on the optimization...
-
Opinia dotycząca jakości wykonania elementów balustrad przystanków PKM oraz możliwych przyczyn występowania korozji
PublicationSporządzono opinię dotycząca występowania korozji elementów konstrukcyjnych balustrad na przystankach kolei PKM. Wskazano możliwe przyczyny korozji.
-
Modified SPWM Technique with Zero-Sequence Voltage Injection for a Five-Phase, Three-Level NPC Inverter
PublicationThis article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the reference modulating signals; hence enabling the effective utilization of the DC-link voltage. Balanced split-input DC-link voltages were achieved through further incorporation of adjustable...
-
Dydaktyka PKM w Katedrze Konstrukcji i Eksploatacji Maszyn na Wydziale Mechanicznym Politechniki Gdańskiej
PublicationW referacie przedstawiono strukturę przedmiotu PKM wykładanego na Wydz. Mechan. PG. Przedstawiono przykłady zadań projektowych, charakterystykę przedmiotu, warunki zaliczeń.
-
MutL protein as a constituent of vsp, ner and mmr repair systems
PublicationMutS and MutL proteins are renowned mostly for their functions in well-characterized, post-DNA replication mis- match repair system (MMR). However, there is growing evidence that MMR system is not the only field of action for these pro- teins. Moreover, the participation in MMR does not even have to be their primary function. There are some reports indicat- ing involvement of MutL in BER, NER and VSP (very short patch repair)....
-
Shoreline Extraction Based on LiDAR Data Obtained Using an USV
PublicationThis article explores the use of Light Detection And Ranging (LiDAR) derived point clouds to extract the shoreline of the Lake Kłodno (Poland), based on their geometry properties. The data collection was performed using the Velodyne VLP‐16 laser scanner, which was mounted on the HydroDron Unmanned Surface Vehicle (USV). A modified version of the shoreline extraction method proposed by Xu et al. was employed, comprising of the following...
-
Badanie wierności brzmienia dźwięku instrumentów wirtualnych VST/TRTAS
PublicationTematem referatu jest subiektywne badanie wierności brzmienia instrumentów wirtualnych (VST/TRTAS) wykorzystujących próbkowanie dźwięków rzeczywistych instrumentów muzycznych. Na potrzeby przedstawionej pracy wybrano kilka utworów muzyki orkiestrowej z epoki romantyzmu i klasycyzmu, nagranych przy użyciu instrumentów akustycznych. Następnie zaaranżowano fragmenty tych utworów, wykorzystując do tego instrumenty wirtualne i efekty...
-
VUV photofragmentation of the six-membered heterocyclic molecules containing oxygen
PublicationCancer is a significant public health concern worldwide, which results in millions of deaths each year. The standard cure routine for cancer is surgery, and nowadays, radiotherapy or a hadrontherapy. Depending on the type of cancer, patients may undergo additional treatment, including targeted therapy. A combination of radio- or hadron-therapy with proper drug treatment can inhibit the proliferation of cancer cells and thus can...
-
Armin Mikos von Rohrscheidt, Historia w turystyce kulturowej, Wydawnictwo PWN, Warszawa 2018, ss. 378.
PublicationRecenzja książki: A. Mikos von Rohrscheidt, Historia w turystyce kulturowej.
-
Study on effective front region thickness of PCM in thermal energy storage using a novel semi-theoretical model
PublicationThermal energy storage in mobile applications, particularly battery of electric vehicles, is currently gaining a lot of importance. In this paper, a semi-theoretical time-dependent mathematical model of the phase change in a double shell thermal energy storage module has been developed where the inner tube is a heat exchange surface. An effective front region thickness for the melting and solidification process has been studied....
-
Sztuczny sensor smaku a zmysł smaku
PublicationOmówiono klasy smaku i działanie zmysłu smaku, który odgrywa ogromną rolę w ocenie jakości żywności metodami organoleptycznymi. Metody te nie są w pełni obiektywne, stąd poszukuje się sztucznego sensora smaku. Przedstawiono szereg rozwiązań prowadzących do opracowania sensora smaku na większą skalę. Omówiono wybrane potencjometryczne i woltamperometryczne sensory smaku, a także ich handlowe modele.
-
Estimation of interior-permanent-magnet-synchronous-motor rotor position by analysis of phase-current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM rotor angular position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Calculation of the motor position is performed in every PWM cycle. The standard SV-PWM method is used to determine...
-
Modelowanie procesu nagrzewania pompy wielotłoczkowej PWK 27 firmy HYDROTOR podczas rozruchu w niskich temperaturach otoczenia
PublicationW artykule przedstawiono modelowanie procesów nagrzewania pompy wielotłoczkowej PWK 27 firmy HYDROTOR podczas rozruchu w niskich temperaturach otoczenia (warunkach szoku termicznego).
-
Model odzieży ciepłochronnej z funkcją termoregulacji, wykorzystującej aerożel i materiały przemiany fazowej (PCM) – badania wstępne
Publication -
Identification of Public Service Logic (PSL) and Public Service Motivation (PSM) elements in Open Government Data (OGD) initiatives
PublicationWhile previous research on Open Government Data (OGD) has primarily focused on reuse and adoption, this study aims to explore the implications of the Public Service Logic (PSL) and Public Service Motivation (PSM) dimensions in the context of OGD initiatives. This study is contextualized in Tanzania wherein the OGD initiatives are at an evolving stage. For the present study, the perspectives of the 15 public officials involved in...
-
Investigation of the Effect of The Temperature and Magnetization Pattern on Flux Density, Instantaneous Torque, Unbalanced Magnetic Forces of a Surface Inset PMM
PublicationElectrical machines utilized in domestic applications such as ceiling fans should have low losses and cost. Permanent magnets are used instead of rotor excitation to reduce losses. Therefore, not only the losses of the rotor winding are eliminated, but also the efficiency of the machine is increased. A surface inset consequent pole (SICP) machine has also been used to reduce costs. Because less magnets are utilized in this structure....
-
VSC converters control for offshore wind farms HVDC grid connection
PublicationThe paper proposes a voltage sourced converter (VSC) new control method. A well-known in the electric power systems correlation between voltage angle and active power and correlation between voltage and reactive power is used instead of feedforward control. This allows for a fast and almost independent control of active and reactive power flow.
-
IPMSM rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM angular rotor position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Algorithm is characterised by a very simple formulae. The calculation of rotor position is performed in every PWM...
-
Computer aided materials design of PM duplex stainless steels
Publication -
A concept for reducing PM 10 emissions for car brakes by 50%
PublicationWith regard to airborne particles with an aerodynamic diameter of less than 10 μm (PM10), in countries in the European Union, the mass of brake emissions equals approximately 8–27% of the total traffic-related emissions. Using a research methodology combining tests at different scale levels with contact mechanics simulations and PM10 chemical characterization, the REBRAKE EU-financed project had the following aims: i) to demonstrate...
-
PM Motor Controller for an Electric Vehicle with Separate Wheel Drives
PublicationDla pojazdu z elektrycznym niezależnym napędem kół, przedstawiono propozycję hierarchicznej struktury sprzętowej, z jednostką centralną koordynującą sterowanie poszczególnymi silnikami przez sterowniki podporządkowane, realizujące regulację momentu silnika w trybie rozruchu i hamowania. Zaproponowano algorytmy sterowania silnikiem synchronicznym z magnesami trwałymi, a także protokół komunikacji między sterownikami. Przedstawiono...
-
Experimental and theoretical study of a vertical tube in shell storage unit with biodegradable PCM for low temperature thermal energy storage applications
PublicationThis article presents the experimental investigations of the coconut oil-based TES module for HVAC applications in the ambient and-sub ambient temperature range. To properly study this problem modular experimental module and test loop were developed. Special attention has been paid to study the physical mechanism of the melting/solidification process for natural substance (coconut oil) which has perspectives to be used in thermal...
-
Analiza możliwości zastosowania materiałów PCM do magazynowania ciepła w budynkach w celu zapewnienia komfortu cieplnego pomieszczeń
PublicationCelem pracy było przeprowadzenie analizy porównawczej, mającej wskazać potencjalne możliwości poprawy ogólnej efektywności energetycznej budynków, poprzez zastosowanie materiałów zmiennofazowych (PCM).
-
MUTL PROTEIN AS A COMMON CONSTITUENT OF VSP, BER, NER AND MMR REPAIR SYSTEMS
PublicationMutS and MutL proteins are renowned mostly for their functions in well-characterized, post-DNA replication mismatch repair system (MMR). However, there is growing evidence that MMR system is not the only field of action of these proteins. Moreover, involvement in MMR does not even have to be their primary function. There are some reports indicating involvement of MutL in BER, NER and VSP (very short patch repair). MutL protein...
-
Small power laboratory model and high power prototype of the four-level VSI
Publication -
Examining the Impact of Distance Between VSL Road Signs on Vehicle Speed Variance
PublicationVariable speed limit (VSL) is an intelligent transportation system (ITS) solution for traffic management. The speed limits can be changed dynamically to adapt to traffic conditions such as visibility and traffic volume, curvature, and grip coefficient of the road surface. The VSL traffic sign location problem and attempts to solve it using computer simulation are presented in this paper. Experiments on a selected road segment,...
-
Sensorless control of five-phase induction machine supplied by the VSI with output filter
PublicationIn this paper, a novel sensorless control structure based on multi-scalar variables is proposed. The tatic feedback control law is obtained by using the multi-scalar variables transformation, where the multi-scalar variables approach allows a full linearization of the nonlinear system. The control system could be described as “optimized” because of the minimized number of controllers. Furthermore, control system is divided into...
-
A new approach to determination of the two-mass model parameters of railway current collector
PublicationThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
-
A new approach to determination of the two-mass model parameters of railway current collector
PublicationThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
-
Kompensacja wpływu czasu martwego i spadków napięcia na przewodzących elementach półprzewodnikowych w falowniku napięcia.
PublicationW artykule przedstawiono metodę kompensacji wpływu czasu martwego i spadków napięcia na przewodzących elementach półprzewodnikowych. Zaprezentowano wyniki badań symulacyjnych i eksperymentalnych, które dowodzą, iż zaproponowana metoda kompensacji efektywnie zmniejsza wpływ zniekształceń napięcia na wyjściu falownika w szerokim zakresie zmian wartości częstotliwości nośnej w przypadku modulacji PWM oraz RPWM.
-
Energy conversion in small water plants with variable speed PM generator
Publication