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Reading Teacher (The)
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GENETIC TESTING
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Mariusz Kaczmarek dr hab. inż.
PeopleReceived M.Sc., Eng. in Electronics in 1995 from Gdansk University of Technology, Ph.D. in Medical Electronics in 2003 and habilitation in Biocybernetics and Biomedical Engineering in 2017. He was an investigator in about 13 projects receiving a number of awards, including four best papers, practical innovations (7 medals and awards) and also the Andronicos G. Kantsios Award and Siemens Award. Main research activities: the issues...
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Acoustic heating produced in resonators filled by a newtonian fluid
PublicationAcoustic heating in resonators is studied. The governing equation of acoustic heating is derived by means of the special linear combination of conservation equations in differential form, allowing the reduction of all acoustic terms in the linear part of the final equation, but preserving terms belonging to the thermal mode responsible for heating. This equation is instantaneous and includes nonlinear acoustic terms that form a...
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HIGH TEMPERATURE HEAT PUMPS – PERSPECTIVE HEATING SYSTEMS?
PublicationIn the paper presented are authors own concepts of high temperature compressor heat pumps for the utilisation of medium and low temperature sources of heat. Working fluids for use in high temperature heat pumps are discussed, as well as the criteria for their selection. Analyses are presented for the production of in the upper steam source at 130 °C. One-stage systems and cascade systems were analyzed. An analysis of the coefficient...
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An advanced Thermal-FSI approach to flow heating/cooling
PublicationActually, two-way thermal-energy exchange between working fluid and solid material of a casing is a leading problem for modern – semi automatic – design techniques. Many questions should be solved, especially, the turbulent mode of thermal energy transport both in fluid and solid, should be re-examined and reformulated from the primary principles. In the present paper, a group of researchers from Energy Conversion Department of...
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Thermally stimulated currents in disordered solids at step heating
PublicationW pracy podano rezultaty badań teoretycznych prądów termicznie stymulowanych (TSC) w nieuporządkowanych ciałach stałych, wywołanych krokowym ogrzewaniem próbki. Rozszerzono metodę Gobrechta-Hofmanna analizy TSC na przypadek znaczącego powtórnego pułapkowania nośników. Rozpatrzono TSC mierzone w próbkach o konfiguracji koplanarnej i kanapkowej. Głównymi czynnikami ograniczającymi TSC są wówczas odpowiednio: rekombinacja monomolekularna...
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The effect of heating and fermenting on antioxidant properties of white cabbage
PublicationIt is widely believed that natural antioxidants found in food are significantly lost during processing. Nevertheless, it was recently demonstrated that processed fruits and vegetables may retain their antioxidant activity. In the present work, the changes in the overall antioxidant properties as a consequence of fermentation of cabbage and/or heat treatment of cabbage juices and extracts were studied. Fermentation processes as...
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Modelling of acoustic heating induced by different types of sound
PublicationWyprowadzono równanie dynamiczne sterujące ogrzewaniem na skutek strat energii fali akustycznej dowolnego typu, okresowej i nieokresowej, w płynie ze standardową dyssypacją i przewodnictwem ciepła. Zbadano efektywność ogrzewania w przypadku dźwięku stochastycznego i regularnego.
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Computer simulation of induction heating system with series inverter
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Induction heating in estimation of thermal properties of conductive materials
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Impedance matching in dual-frequency induction heating systems
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Cement composites with expanded graphite as resistance heating elements
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Simulation of temperature field in cylindrical boiling heating section
PublicationW pracy przedstawiono wyniki obliczeń cylindrycznej sekcji grzejnej. Biorąc pod uwagę geometrię i konstrukcję sekcji grzejnej zaprezentowano rozwiązania pola temperatury dla cylindrycznej sekcji grzejenej. W uzyskaniu rozwiązania posłużono się metodą elementów skończonych.
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Energy-Recovery Pressure-Reducer in District Heating System
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Acoustic heating produced in the thermoviscous flow of a bingham plastic
PublicationThis study is devoted to the instantaneous acoustic heating of a Bingham plastic. The model of the Bingham plastic's viscous stress tensor includes the yield stress along with the shear viscosity, which differentiates a Bingham plastic from a viscous Newtonian fluid. A special linear combination of the conservation equations in differential form makes it possible to reduce all acoustic terms in the linear part of of the final equation...
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Biomass potential for heating and electricity purposes in pomeranian region
PublicationW referacie dokonano analizy odnawialnych źródeł energii (RES), użytecznych w obszarze Pomorza z punktu widzenia produkcji ciepła. Każdy Urząd Gminy dokonuje szacowań z uwzględnieniem swojego potencjału RES. W dwóch przypadkach istnieje potencjał w postaci słomy, który może w 100% pokryć zapotrzebowanie na ciepło (ciepło produkowane w kotłach opalanych słomą). Jeden z przypadków omówiono w szczegółach.
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MAGNETOACOUSTIC HEATING AND STREAMING IN A PLASMA WITH FINITE ELECTRICAL CONDUCTIVITY
PublicationNonlinear effects of planar and quasi-planar magnetosound perturbations are discussed. Plasma is assumed to be an ideal gas with a finite electrical conductivity permeated by a magnetic filed orthogonal to the trajectories of gas particles. the excitation of non-wave modes in the filed of intense magnetoacoustic perturbations, i.e., magnetoaciustic heating and streaming, is discussed. The analysis includes a derivation if instantaneous...
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Study of the effect of adiabatic heating on the operation of the electrodynamic actuator
PublicationElectrodynamic actuators are used in hybrid switching systems where a very quick contact separation as well as operation repeatability and long-term reliability are required. The article presents selected results of thermal studies in the electrodynamic drive system. Study was carried out on the basis of the 3D electromagneto-thermal model implemented in the Ansys_Maxwell environment. The present model allows to determine the critical...
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Acoustic heating produced in the thermoviscous flow of a Bingham plastic
PublicationThis study is devoted to the instantaneous acoustic heating of a Bingham plastic. The model of the Bingham plastic's viscous stress tensor includes the yield stress along with the shear viscosity, which differentiates a Bingham plastic from a viscous Newtonian fluid. A special linear combination of the conservation equations in differential form makes it possible to reduce all acoustic terms in the linear part of of the final equation...
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Geothermal heating plant with a combustion engine heat pump.
PublicationPrzedstawiono koncepcję ciepłowni geotermalnej zagospodarowującej zasoby energii zawarte w nisko i średniotemperaturowej wodzie termalnej. W tym celu zaproponowano zastosowanie pompy grzejnej napędzanej silnikiem spalinowym.
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On measurements applied in scientific researches of microwave heating processes
PublicationPrzedstawiono trudności techniczne wykonywania pomiarów w systemach gdzie stosuje się duże poziomy mocy mikrofalowej. Omówiono zasadę pracy do badania procesu grzania mikrofalowego oraz wybrane problemy występujące przy realizacji takiego systemu. Uzasadniono celowość prowadzenia przedstawionych rodzajów pomiarów w badaniach procesów grzania mikrofalowego materiałów.
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Errors caused by microwave part of the microwave heating system
PublicationPrzedstawiono skrótowo zasadę pracy i konstrukcję systemu do badań naukowych procesów grzania mikrofalowego. Wyprowadzono wyrażenie opisujące wartość średniokwadratową błędu pomiaru energii mikrofalowej i przeanalizowano składowe błędu pomiaru powodowane przez rzeczywiście występujące w układzie pomiarowym parametry techniczne jego części mikrofalowej.
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Multimedia Applications for the Hearing Impaired.
PublicationJednym z elementów przeciwdziałania szybko narastającym zagrożeniom niedosłuchem są aplikacje oprate na nowoczesnych technologiach. W wyniku współpracy Katedry Systemów Multimedialnych PG z warszawskim Instytutem Fizjologii i Patologii Słuchu opracowano wdrożone na szeroką skale multimedialne systemy przesiewowych badań zmysłów komunikowania się. Ponadto, nowsze opracowania dotyczą maskowania szumów usznych z wykorzystaniem linearyzacji...
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Code Obfuscation. Where is it Heading?
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Hypertension and cochlear hearing loss
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Power Electronics Building Blocks for implementing Smart MV/LV Distribution Transformers for Smart Grid
PublicationWith an observed increase in the involvement of active consumers in activities aimed at improving energy efficiency and increasing interest in producing energy from renewable sources, there is a need for the development of new technologies enabling the distribution network operators to offer new services and functionalities. Smart MV/LV distribution transformers are characterized by a compact three-stage design, including an...
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Modification of the operating point of residual current transformers for high frequency earth fault currents detection
PublicationFor protection against electric shock in low voltage systems residual current devices are commonly used. However, their proper operation can be interfered when earth fault current with high frequency components occurs. Serious hazard of electrocution exists then. One of the most important element of residual current devices is a residual current transformer with iron core. Tripping characteristic of residual current devices strictly...
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On deterministic procedures for low-cost multi-objective design optimization of miniaturized impedance matching transformers
PublicationPurpose This paper aims to investigate deterministic strategies for low-cost multi-objective design optimization of compact microwave structures, specifically, impedance matching transformers. The considered methods involve surrogate modeling techniques and variable-fidelity electromagnetic (EM) simulations. In contrary to majority of conventional approaches, they do not rely on population-based metaheuristics, which permit lowering...
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Surrogate modeling of impedance matching transformers by means of variable‐fidelity electromagnetic simulations and nested cokriging
PublicationAccurate performance evaluation of microwave components can be carried out using full‐wave electromagnetic (EM) simulation tools, routinely employed for circuit verification but also in the design process itself. Unfortunately, the computational cost of EM‐driven design may be high. This is especially pertinent to tasks entailing considerable number of simulations (eg, parametric optimization, statistical analysis). A possible...
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Influence of circuit breaker operation upon transformeros residual flux and inrush current
PublicationPrzedstawiono model i wyniki obliczeń prądu i strumienia magnetycznego w układzie zawierającym transformator trójfazowy i wyłącznik. Opracowano obwodowy model łącznika z łukiem elektrycznym. Model łuku zbudowano w oparciu o jego statyczną charakterystykę prądowo-napięciową z uwzględnieniem uproszczonej charakterystyki dynamicznej. Przeprowadzone symulacje wykazały, że wartość maksymalna prądu włączania transformatora zależy zarówno...
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Numerical calculation of three-phase transformer's residual flux in ATP and PSpice programs.
PublicationW artykule przedstawiono analizę przebiegów prądu i strumienia magnetycznego podczas wyłączania transformatora energetycznego, wykonaną w celu określenia strumieni szczątkowych. Wykorzystano do tego celu modele obwodowe zbudowane w oparciu o programy symulacyjne ATP (Alternative Transients Program) i PSpice. Wyniki obliczeń okazały się bardzo zbliżone dla obu modeli. Przy ich wykorzystaniu obliczono strumienie szczątkowe w kolumnach...
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Assessment of the Effectiveness of a Short-term Hearing Aid Use in Patients with Different Degrees of Hearing Loss
PublicationThe study presents evaluating the effectiveness of the hearing aid fitting process in the short-term use (7 days). The evaluation method consists of a survey based on the APHAB (Abbreviated Profile of Hearing Aid Benefit) questionnaire. Additional criteria such as a degree of hearing loss, number of hours and days of hearing aid use as well as the user’s experience were also taken into consideration. The outcomes of the benefit...
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Smart MV/LV distribution transformer for Smart Grid with active prosumer participation
PublicationWraz 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...
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Coordination of generator transformer controller and multi-parameter generator controller regulation algotrithms
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Simplified saturation modelling in three-leg power transformer for the system stability analisys
PublicationThe paper presents a simplified method for modelling non-linearity of the magnetic circuit of the power transformer. The saturation effect is implemented by describing the self and mutual inductances as a function of the magnetic flux. The most important element of this function is the saturation coefficient which is calculated based on transient state during the unloaded transformer switch on. The transformer model is described...
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Detection of inter-turn faults in transformer winding using the capacitor discharge method
PublicationThe paper presents results of an analysis of inter-turn fault effects on the voltage and current waveforms of a capacitor discharge through transformer windings. The research was conducted in the frame of the Facility of Antiproton and Ion Research project which goal is to build a new international accelerator facility that utilizes superconducting magnets. For the sake of electrical quality assurance of the superconducting magnet...
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Experimental investigations of interturn faults in transformer winding using frequency response analysis
PublicationW referacie przedstawiono wyniki badań eksperymentalnych specjalnego Transformatora Trakcyjnego o Zredukowanej Skali (TTZS) z wykorzystaniem metody analizy odpowiedzi w dziedzinie częstotliwości. Pokazano wybrane wyniki analiza FRA nieuszkodzonych symetrycznych uzwojeń strony wtórnej. Zmierzono widmo amplitudowe w przypadku zwarć zwojowych pojedynczych zwojów niektórych cewek. Wykazano, że miejsce wystąpienia zwarcia zwojowego...
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Distribution Transformer with Multi-Zone Voltage Regulation for Smart Grid System Application
PublicationThe article presents four concepts of the multi-zone voltage regulation (MZVR) system. It is a combination of a distribution transformer with an on-load tap-changer, for step voltage regulation, and a power electronic converter, dimensioned for a fraction of MZVR power, realizing continuous voltage regulation, supplemented by a special switch, the so-called bypass. This allows voltage regulation at high resolution, wide range and...
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Central heating temperature control algorithm for systems with condensing boilers
PublicationThe problem of control of a central heating system in a small residence is considered. It is assumed that the system is based on a condensing boiler. Since the boiler efficiency depends on a returning water temperature, the proposed control goal is to provide proper air temperature in the residence as well as the lowest possible water temperature. The proposed algorithm is applied to two buildings. Both of them have the same heating...
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Autonomous Energy Matching Control in an LLC Induction Heating Generator
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Dual-Frequency Induction Heating Generator With Adjustable Impedance Matching
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Heat calculations for water-cooled radiators of the inverter for induction heating
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