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Rough Set Based Modeling and Visualization of the Acoustic Field Around the Human Head
PublicationThe presented research aims at modeling acoustical wave propagation phenomena by applying rough set theory in a novel manner. In a typical listening environment sound intensity is determined by numerous factors: a distance from a sound source, signal levels and frequencies, obstacles’ locations and sizes. Contrarily, a free-field is characterized by direct, unimpeded propagation of the acoustical waves. The proposed approach is...
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Progressive failure analysis of laminates in the framework of 6-field nonlinear shell theory
PublicationThe paper presents the model of progressive failure analysis of laminates incorporated into the 6-field non-linear shell theory with non-symmetrical strain measures of Cosserat type. Such a theory is specially recommended in the analysis of shells with intersections due to its specific kinematics including the so-called drilling rotation. As a consequence of asymmetry of strain measures, modified laminates failure criteria must...
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FEM analysis of composite materials failure in nonlinear six field shell theory
PublicationThe monography deals with the problem of failure initiation in thin laminated composites. Known techniques of laminate structures modelling are briefly characterised. Eventually, shell based approach is chosen for the purpose of the description of the composite structures behaviour, as it predicts their deformation and states of stress effectively in a global sense. The nonlinear six parameter shell theory (6p theory) with asymmetric...
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Field Tests on Hydrodynamic and Hybrid Operation of a Bidirectional Thrust Bearing of a Pump-Turbine
PublicationIn vertical shaft pump turbines operating in pumped storage power plants an important role is played by a thrust bearing. Due to the bidirectional character of operation, thrust bearing tilting pads have to be supported symmetrically, which is known to be unfavourable from the point of view of their performance. Large thrust bearings have to be carefully designed so as to minimise excessive thermo-elastic pad deformations. The...
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Social Entrepreneurship Avenues for the Field Development through Research Paradigm Intersection Discussion
PublicationThe aim of this paper is to identify and provide key arguments for employing integrative approach in the choice of research paradigm for studying social entrepreneurship phenomenon. The fact that social entrepreneurship as a field of research is at its preliminary stage, serves as argument and gives freedom in the discussion of the choice of employing a research paradigm. The author does so through identifying commonalities and...
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Identification of aromatic compounds in odours mixture by gas chromatography and field olfactometry techniques
PublicationThis paper shows the results of investigation on identification aromatic compounds present in odorous mixture in atmospheric air samples collected in a vicinity of the oil refinery LOTOS S.A., located in Gdansk, during March and April period have be presented. The studies were conducted by the use of comprehensive two-dimensional gas chromatograph equipped with a cryogenic modulator and coupled with a time-of-flight mass spectrometer,...
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Analysis of the influence of ferromagnetic contaminations in plastics on the measurements of disturbances of magnetic field of the Earth
PublicationPlastics can be contaminated with small particles or filings with ferromagnetic properties. These contaminations cause significant disturbances in the magnetic field in the case of taking measurements of very low magnetic fields. The analysis of the influence of contaminated plastics on magnetic measurements is presented in this paper.
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The effect of fixed adsorption bed height on adsorption of gaseous mixture of volatile organic compounds
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Exploring perceptions of pro environmental educational mobile applications based on semantic field analysis
PublicationThe paper aims to identify multidimensional perceptions of mobile apps by their users. Special attention has been paid to pro-environmental educational apps. Semantic field analysis and measurement of emotional temperatures were performed to achieve this goal. Transcripts from seven focus group interviews were used as research material. The results indicate that functionality based on a reward or benefit system reinforces environmentally...
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Oiled soil washing in dynamic conditions by micellar surfactants solutions and obtained effluents treatment
PublicationZbadano możliwość zastosowania micelarnych roztworów biosurfaktantu (JBR 425), surfaktantów syntetycznych (Rokanolu NL5, NL6, NL8) i ich mieszanin (Rokanol NL6 : JBR 425) do wymywania oleju syntetycznego z gruntu w procesie mycia gleby w warunkach dynamicznych. Micelarne roztwory Rokanolu NL6 oraz NL8 wykazały nieznacznie wyższą efektywność wymywania oleju z gruntu w porównaniu z efektywnością usuwania oleju przy pomocy roztworów...
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Electric field and charge induced quenching of luminescence in electroluminescent emitters based on lanthanide complexes
PublicationW pracy badano ładunkowe i elektrycznopolowe wygaszanie ekscytonóww układzie dwuamina TPD: organiczny kompleks europu przez pomiar zaników fotoluminescencji w zewnętrznym polu elektrycznym.
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Spectral analysis of nonstationary low-frequency magnetic-field emissions from ship's power
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Application of matching pursuit based method to identify sources of time-vary magnetic field
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Numerical Simulation of Temperature Field in Steel under Action of Electron Beam Heating Source
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Low-Field NMR Study of Shortcake Biscuits with Cricket Powder, and Their Nutritional and Physical Characteristics
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Low Field NMR Studies of Wheat Bread Enriched with Potato Juice During Staling
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Phylogenetic and geographic analysis of fowl adenovirus field strains isolated from poultry in Poland
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Comparative study on homogeneity, filling ratio and purity of iron filled multiwalled carbon nanostructures
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Effect of GO-Fe3O4 and rotating magnetic field on cellular metabolic activity of mammalian cells
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Cisplatin filled multiwalled carbon nanotubes – a novel molecular hybrid of anticancer drug container
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Dynamic Formation and Breaking of Disulfide Bonds in Molecular Dynamics Simulations with the UNRES Force Field
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Replica Exchange and Multicanonical Algorithms with the Coarse-Grained United-Residue (UNRES) Force Field
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Analysis of Reliability Structures for Fire Signaling Systems in the Field of Fire Safety and Hardware Requirements
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Large electric field effects on photoluminescence of organic Eu3+ complex-based electroluminescent emitters
PublicationW pracy zaobserwowano silne wygaszenie fotoluminescencji pod wpływem zewnętrznego pola elektrycznego w organicznym kompleksie europu Eu(III). Wygaszenie fotoluminescencji przypisano elektrycznopolowej dysocjacji ekscytonów oraz anihilacji ekscytonów na wstrzykniętym do próbki ładunku elektrycznym.
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Propagation in a ferrite circular waveguide magnetized through a rotary four-pole magnetic field
PublicationOpracowano uproszczony model matematyczny użyteczny do badania zjawisk polowych występujących w falowodzie cylindrycznym magnesowanym czterobiegunowym polem obrotowym. Wykazano, że falowód ten może być wykorzystany jako przesuwnik fazy lub układ zmieniający polaryzację.
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Affymetrix Chip Definition Files Construction Based on Custom Probe Set Annotation Database
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Numerical Estimate of the Spectral Resonance Structure Frequency Scale of Natural ULF Magnetic Field
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Geomagnetic Storms and Substorms as Space Weather I nfluence on Atmospheric Electric Field Variations
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Simplified method of simulation of temperature field control system of induction heated calender rolls
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Dielectric response of electric-field distortions of the twist-bend nematic phase for LC dimers
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A Strategy to Locate Fixed Points and Global Perturbations of ODE’s: Mixing Topology with Metric Conditions
PublicationIn this paper we discuss a topological treatment for the planar system z' = f (t, z) + g(t, z) where f and g are T -periodic in time and g(t, z) is bounded. Namely, we study the effect of g(t, z) in two different frameworks: isochronous centers and time periodic systems having subharmonics. The main tool employed in the proofs consists of a topological strategy to locate fixed points in the class of orientation preserving embedding...
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Dielectric properties of modified graphene oxide filled polyurethane nanocomposites and its correlation with rheology
PublicationThis study aims at investigating the dynamic mechanical, dielectric and rheological properties of reinforced polyurethane (PU) nanocomposites containing hydrophilic graphene oxide (GO) and/or hydrophobic modified graphene oxide (mGO) sheets. The organic modification of GO was performed with 4,4′-methylenebis (phenyl isocyanate) (MDI) and the samples were prepared by solvent mixing. We found that addition of mGO provides a more...
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Stress anisotropy characterisation with the help of Barkhausen effect detector with adjustable magnetic field direction
PublicationIn the paper we describe a novel apparatus for the measurement of the Barkhausen noise (BN) angular dependence, which in turn may be indicative of the stress induced anisotropy of magnetic properties. Such dependence can be further used for the stress distribution evaluation. The change of magnetization direction in the material is obtained by varying the magnetic flux density in two perpendicular yokes of the apparatus. We present...
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Spatial Calibration of a Dual PTZ-Fixed Camera System for Tracking Moving Objects in Video
PublicationA dual camera setup is proposed, consisting of a fixed (stationary) camera and a pan-tilt-zoom (PTZ) camera, employed in an automatic video surveillance system. The PTZ camera is zoomed in on a selected point in the fixed camera view and it may automatically track a moving object. For this purpose, two camera spatial calibration procedures are proposed. The PTZ camera is calibrated in relation to the fixed camera image, using interpolated...
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Morphology of bio-based polyurethane composites filled by mer-cerized or silanized natural fibres
PublicationBio-composites are materials which possess unique properties and undergo biodegra-dation under specific conditions. Bio-composites belong to the group of materials produced with the use of renewable raw materials. They contain reinforcement, mainly in the form of natural fiber, which has high stiffness and resistance; filler powders are less frequently used. Significant features of natural fibers are elongation, density, thermal...
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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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Influence of plastic deformation on stray magnetic field distribution of soft magnetic steel sample
PublicationThe effect of various combinations of conditions, i.e., presence of the Earth’s magnetic field during and after deformation on the distribution of stray magnetic field of S355 steel sample, which is locally deformed, was investigated. Some of the stages of the experiment were carried out in zero magnetic field. Compensation of the Earth’s magnetic field was obtained by the application of a pair of Helmholtz coils. These coils are...
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Extraction of antenna pattern from near field antenna measurements distorted by undesired emission
PublicationIn this paper authors present experimental correction of antenna pattern obtained from near field measurements when they are distorted by determined electromagnetic emission. Such situation may be met e.g. when feeding or supply subsystem interacts with antenna radiation pattern due to self-emission. Presented results of experiments show effectiveness of extraction of antenna pattern utilizing near field antenna measurements.
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Estimation of the effectiveness of nbpt for limiting ammonia emission from urea based on the field experiments
PublicationThe efectiveness of the ammonia emission reduction from NBPT-stabilized urea was investigating in 2011 during a field experiment on a grassland plot fertilized with a one-time dose of 60 kgN/ha. The obtained reduction coefficient of ammonia emission equaled 73% and 39-51% relative to erea without the inhibitor and ammonium nitrate, respectively.
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Air journal bearing utilizing near-field acoustic levitation: stationary shaft case
PublicationResults of a study to examine a unique idea of self-levitating journal bearing are presented in this paper. the idea represents a radical departure from the current bearing technology. it utilisesacoustic levitation, which relies on the sound energy radiated by an object supporting a load. acoustic levitation has been demonstrated to support loads of up to 10 kg. in order to support a load theacoustic wave emitted by the radiating...
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Antimicrobial properties of pristine and Pt-modified titania P25 in rotating magnetic field conditions
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A new time-frequency detection method of stray current field interferenceon metal structures.
PublicationA new detection method has been presented of stray current field interference on underground metal structures. The method employs short time Fourier transformation (STFT). This method of analysis allows determination of signal spectral power density changes (e.g., structure potential) in the function of time. In the paper results have been presented of total time–frequency analysis of a pipeline potential in a stray current field...
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Physical and numerical modelling of heat-flow processes in tangentially pulverized fuel-fired boiler
PublicationPraca przedstawia wykorzystanie eksperymentalnego modelowania fizycznego kwasowo-zasadowego do modernizacji kotła pyłowego z tangencjalną komorą spalania w aspekcie ograniczenia emisji toksycznych składników węgla, siarki i azotu oraz doboru optymalnych parametrów termodynamicznych mieszania i spalania. Dodatkowo, w celu porównania wyników pomiarów kotła po modernizacji, wykonano obliczenia numeryczne z zastosowaniem oprogramowania...
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Design of hight voltage busbar: trade off between electrical field and stray inductance
PublicationArtykuł dotyczy optymalizacji konstrukcji i technologii szyny doprowadzenia zasilania do pojedynczej gałęzi falownika średniego napięcia. Dla szeregowego układu złożonego z trzech modułów elektroizolowanych (6 par tranzystorów i diod) rozważono warianty geometrii szyny zasilania przy uwzględnieniu wypadkowej indukcyjności obwodu komutacyjnego. Wyznaczono główne składniki indukcyjności rozproszenia oraz wykazano jej wpływ na przepięcia...
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Optimizing acoustic field intesity algorithms using the sound ray surface density method.
PublicationW artykule przedstawiono zagadnienia optymalizacji algorytmów komputerowych obliczeń rozkładów natężeń pola akustycznego w akwenie w zależności od za- mierzonych warunków hydrologicznych pod kątem skrócenia czasu obliczń.
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Experimental and theoretical investigation into pressure field in a shroud clearance. Part I: Experimental research
PublicationPrzedstawiono wyniki badań eksperymentalnych rozkładu ciśnienia w uszczelnieniu nadbandażowym stopnia powietrznej turbiny modelowej. Badania przeprowadzono dla różnej częstości obrotowej wirnika i różnego obciążenia turbiny. Wyniki porównano z rezultatami obliczeń teoretycznych w II części artykułu.
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Physical and numerical modelling of flow pattern and combustion process in pulverized fuel fired boiler.
PublicationW pracy przedstawiono źródła powstawania toksycznych związków podczas procesu spalania, metody ich redukcji. Do tego zadania wykorzystano eksperymentalne modelowanie fizyczne i uzupełniono je modelowaniem numerycznym. Obie metody, techniki modelowania miały na celu optymalizację procesu spalania.Wyniki obliczeń numerycznych porównano z pomiarami.
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A field programmable analog array for CMOS continuous-time OTA-C filter applications
PublicationW artykule opisano programowalny wzmacniacz transkonduktancyjny oraz konfigurowalny blok analogowy CAB składający się ze wzmacniacza transkonduktancyjnego, kluczy oraz programowalnego kondensatora. Z bloków CAB można zbudować uniwersalne, programowalne filtry. Wzmacniacz transkondukancyjny został przesymulowany oraz wykonany w technologii CMOS. Wyniki pomiarów pokazują, że transkonduktancja wzmacniacza może być przestrajana ponad...
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Mechanical, Thermal and Rheological Properties of Polyethylene-Based Composites Filled with Micrometric Aluminum Powder
PublicationInvestigations related to polymer/metal composites are often limited to the analysis of the electrical and thermal conductivity of the materials. The presented study aims to analyze the impact of aluminum (Al) filler content (from 1 to 20 wt%) on the rarely investigated properties of composites based on the high-density polyethylene (HDPE) matrix. The crystalline structure, rheological (melt flow index and oscillatory rheometry),...
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Dynamic fracture of brittle shells in a space-time adaptive isogeometric phase field framework
PublicationPhase field models for fracture prediction gained popularity as the formulation does not require the specification of ad-hoc criteria and no discontinuities are inserted in the body. This work focuses on dynamic crack evolution of brittle shell structures considering large deformations. The energy contributions from in-plane and out-of-plane deformations are separately split into tensile and compressive components and the resulting...