Filters
total: 2583
filtered: 2261
displaying 1000 best results Help
Search results for: PHASE VOCODER
-
Effects of Ni-NCAL and Ni–Ag electrodes on the cell performances of low-temperature solid oxide fuel cells with Sm0.2Ce0·8O2-δ electrolyte at various temperatures
PublicationThree low-temperature solid oxide fuel cells are built using Sm0.2Ce0·8O2-δ (SDC) as the electrolyte. Cell A is symmetrical and features Ni–LiNi0.8Co0·15Al0·05O2 (Ni–NCAL) electrodes, Cell B comprises a Ni–NCAL anode and a Ni–Ag cathode, and Cell C is fabricated using a Ni–NCAL cathode and a Ni–Ag anode. The ohmic resistance and polarization resistance (Rp) of Cells B and C are significantly higher than those of Cell A. The reduction...
-
Polytypism and superconductivity in the NbS2 system
PublicationWe report on the phase formation and the superconducting properties in the NbS2 system. Specifically, we have performed a series of standardized solid-state syntheses in this system, which allow us to establish a comprehensive synthesis map for the formation of the two polytypes 2H-NbS2 and 3R-NbS2, respectively. We show that the identification of two polytypes by means of X-ray diffraction is not always unambiguous. Our physical...
-
Pressure drop of HFE7000 and HFE7100 during flow condensation in minichannels
PublicationAttention is focused on the issues of flow resistance and pressure drop of perspective refrigeration fluids during condensation in the two-phase flow in minichannels. The case of the flow through a cylindrical single channel of 2.3 mm inner diameter was carefully analyzed. Pressure drop tests have been performed in diabatic flow conditions. The effect of heat flux, mass flux, vapour quality and saturation temperature on the two-phase...
-
Nitrogen transformations and mass balances in anaerobic/anoxic/aerobic batch experiments with full-scale biomasses from BNR activated sludge systems.
PublicationThe aim of this study was to investigate nitrogen mass balances occurring inside full-scale BNR activated sludge systems, with special attention to colloidal and dissolved organic nitrogen (CON and DON) transformations. For this purpose, laboratory experiments were carried out using process biomass from two large BNR plants in northern Poland. Two parallel batch reactors were operated in a 3-phase (anaerobic/anoxic/aerobic) cycle....
-
Nitrogen transformations and mass balances in anaerobic/anoxic/aerobic batch experiments with full-scale biomasses from BNR activated sludge systems.
PublicationThe aim of this study was to investigate nitrogen mass balances occurring inside full-scale BNR activated sludge systems, with special attention to colloidal and dissolved organic nitrogen (CON and DON) transformations. For this purpose, laboratory experiments were carried out using process biomass from two large BNR plants in northern Poland. Two parallel batch reactors were operated in a 3-phase (anaerobic/anoxic/aerobic) cycle....
-
Feedback Control of Multiphase Induction Machines with Backstepping Technique
PublicationThe paper presents the control possibility of five phase induction machines. In the proposed solution the machine model vector form is not transformed to the (dq)-coordinate system, that is connected to rotor flux vector, but utilizes the stationary system ( αβ ). Moreover, the nonlinear model linearization is based on demonstrated nonlinear variables transformation for i-orthogonal ( αβ )(n) planes. By introducing the backstepping...
-
Cross-Bonding of MV Cable Lines for Energy Losses Decrease
PublicationCurrently, almost all medium voltage cable lines (MV) operate with the return wires earthed at both ends of the cable. Such a way of operation causes that during normal states of operation as well as during disturbances, e.g. short-circuits, in the return wires induce currents whose values mainly depend on the currents flowing in the phase wires. These currents in normal operating states are a source of additional energy losses...
-
Effect of microstructure on mechanical properties of BA1055 bronze castings
PublicationThe article presents research results performed on aluminum bronze CuAl10Fe5Ni5 (BA1032) castings used for marine propellers. Metallographic studies were made on light microscope and a scanning electron microscope to assess quantitatively and qualitatively the alloy microstructure. It has been shown that the shape, size and distribution of the iron-rich phase precipitates in bronze microstructure significantly affect its mechanical...
-
Failure Monitoring and Condition Assessment of Steel-Concrete Adhesive Connection Using Ultrasonic Waves
PublicationAdhesive bonding is increasingly being incorporated into civil engineering applications. Recently, the use of structural adhesives in steel-concrete composite systems is of particular interest. The aim of the study is an experimental investigation of the damage assessment of the connection between steel and concrete during mechanical degradation. Nine specimens consisted of a concrete cube and two adhesively bonded steel plates...
-
Utilization of fuzzy rules in computer character animation
PublicationThe chapter presents a method for automatic enhancement of computer character animation utilizing fuzzy inference. First the user designs a prototype version of animation, with keyframes only for important poses, roughly describing the action. Then animation is enriched with new motion phases calculated by the fuzzy inference system using descriptors given by the user. Various degrees of motion fluency and naturalness are possible...
-
Proton Conducting Ceramic Powder Synthesis by a Low Temperature Method
PublicationMolten salt synthesis (MSS) is a simple method for the preparation of ceramic powders with specific morphology. The main role of the molten salts is to increase the reaction rate and lower the reaction temperature. It occurs because of much higher mobility of reactants in the liquid medium than in the solid state. In this work the molten salt synthesis was applied to produce ceramic powders of La0995Ca0005NbO4 and BaCe09−xZrxY01O3....
-
Service-based Resilience via Shared Protection in Mission-critical Embedded Networks
PublicationMission-critical networks, which for example can be found in autonomous cars and avionics, are complex systems with a multitude of interconnected embedded nodes and various service demands. Their resilience against failures and attacks is a crucial property and has to be already considered in their design phase. In this paper, we introduce a novel approach for optimal joint service allocation and routing, leveraging virtualized...
-
SURFACTANTS IN KLODNICA RIVER (KATOWICE, POLAND). PART II. QUATERNARY AMMONIUM COMPOUNDS
PublicationThe paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative...
-
Fabrication and Crystal Structure of Sol-Gel Deposited BST Thin Films with Compositional Gradient
PublicationIn the present research technology of compositionally graded barium strontium titanate Ba1-xSrxTiO3 thin films deposited on stainless steel substrates by sol-gel spin coating followed with thermal annealing at T = 650°C is reported. Results of thermal behavior of the sol-gel derived powders with compositions used for fabrication of graded structure (i.e. with Sr mole fraction x = 0.5, 0.4 and 0.3) are described. X-ray diffraction...
-
Radioisotope measurement of selected parameters of liquid-gas flow using single detector system
PublicationTo determine the parameters of two-phase flows using radioisotopes, usually two detectors are used. Knowing the distance between them, the velocity of the dispersed phase is calculated based on time delay estimation. Such a measurement system requires the use of two gamma-ray sealed sources. But in some situations it is also possible to determine velocity of dispersed phase using only one scintillation probe and one gamma-ray source....
-
Synthesis, microstructure and electrical properties of nanocrystalline calcium doped lanthanum orthoniobate
PublicationThe single phase lanthanum orthoniobate with tetragonal structure has been synthesized by the means of mechanosynthesis method. The studies have shown the crystal structure of La0.98Ca0.02NbO4 depends on the synthesis stage. The samples were predominantly in the tetragonal phase with a trace amount of the monoclinic phase. The SEM studies of morphology and microstructure have shown nanocrystallinity of the materials. The Raman...
-
Akcelerator predykcji wewnątrzramkowej H.264 do kompresji obrazu w sensorach wizyjnych
PublicationW artykule przedstawiono konfigurowalny cyfrowy akcelerator predykcji wewnątrzramkowej przeznaczony dla enkodera wideo standardu H.264. Akcelerator realizuje predykcję typu „intra” dla makrobloków luminancji o wymiarach 4x4 i 16x16. Akcelerator wstępnie zaimplementowano w układzie FPGA, gdzie został on pomyślnie zweryfikowany, a następnie zaimplementowano go w układzie ASIC w technologii UMC 90 nm. Szczegółowe wyniki testów akceleratora...
-
Akcelerator predykcji wewnątrzramkowej H.264 do kompresji obrazu w sensorach wizyjnych
PublicationW komunikacie przedstawiono konfigurowalny cyfrowy akcelerator predykcji wewnątrzramkowej przeznaczony dla enkodera wideo standardu H.264. Akcelerator realizuje predykcję typu „intra” dla makrobloków luminancji o wymiarach 4x4 i 16x16. Akcelerator wstępnie zaimplementowano w układzie FPGA, gdzie został on pomyślnie zweryfikowany, a następnie zaimplementowano go w układzie ASIC w technologii UMC 90 nm. Szczegółowe wyniki testów...
-
Schemat powstawania rys na przykładzie osiowo rozciąganego pręta żelbetowego
PublicationW artykule przedstawiono w sposób schematyczny ideę powstawania kolejnych rys w konstrukcjach żelbetowych na przykładzie osiowo rozciąganego pręta. Opisano początkowy oraz końcowy stan zarysowania. Wyprowadzono wzór na szerokość rysy. Przedstawiono interpretację geometryczną rys dla fazy początkowego zarysowania oraz efekt tension stiffening na przykładzie elementu osiowo rozciąganego. Przedstawiono przykładowe obliczenia miary...
-
The Influence of Binding Agents on Stiffness of Mineral-cement-emulsion Mixtures
PublicationThis paper attempts to determine the behavior of mineral-cement-emulsion mixture (MCE) under load, whether is it similar to asphalt mixtures (viscoelastic behavior) or to cement treated materials (elastic behavior). To answer this question nine mineral- cement-emulsion mixtures with different combinations of cement and emulsion content were tested in laboratory using Simple Performance Test (SPT). For each mixture stiffness moduli...
-
Characterization of CaTi0.9Fe0.1O3/La0.98Mg0.02NbO4 composite
PublicationA composite of CaTi0.9Fe0.1O3 and electrolyte material, i.e. magnesium doped La0.98Mg0.02NbO4 was prepared and studied. The phase content and the sample microstructure was examined by an X-ray diffraction method and scanning electron microscopy. EDS measurements were done both for composite samples and the diffusion couple. The electrical properties were studied by four terminal DC method. The Ahigh-temperature interaction between...
-
Characterization of magnesium doped lanthanum orthoniobate synthesized by molten salt route
PublicationMolten salt synthesis method has been used to prepare the single phase magnesium doped lanthanum orthoniobate. The phase composition has been checked by X-ray diffraction method and the microstructure studies have been performed by scanning electron microscopy. The high temperature properties of the material have been investigated by thermogravimetry and electrochemical impedance spectroscopy. A dependence between sample total...
-
Calculation of Induced Sheath Voltages in Power Cables – Single Circuit System versus Double Circuit System
PublicationThis paper presents comparison of values of induced sheath voltages in power cable metallic sheaths when one or two cables per phase are used. Calculation of voltages is performed for various phase sequences of the power cables. Three types of the sheaths bonding and earthing are considered. Shock hazard and voltage stress of non-metallic outer sheath of cables are evaluated. The proposed, optimal configuration of the power cable...
-
Determination of Terpene Profile in Cape gooseberry (Physalis peruviana L.) with Use of HS-SPME/GCxGC-TOFMS Method
PublicationFresh fruits and products made of them, especially fruit juice, provide the basic energetic substances (simple and complex sugars) and are a source of health beneficial vitamins, macro and microelements, antioxidants and compounds which are classified together with essential oils (for example terpenes), which positively affect human s health. The terpenes profile of cape gooseberry was determined by headspace solid--phase microextraction...
-
COMPARISON OF TWO MODELS OF CONDENSATION
PublicationIn the low-pressure part of steam turbine, the state path usually crosses the saturation line in penultimate stages. At least last two stages of this part of turbines operate in two –phase region. The liquid phase in this region in mainly created in the process of homogeneous and heterogeneous condensation. Several observations confirm however, that condensation often occurs earlier than it is predicted by theory i.e. before the...
-
Nonlinear and linear impedance of bismuth vanadate ceramics and its relation to structural properties
PublicationThe nonlinear and linear electrical properties, topography, and microstructure of bismuth-vanadate ceramics, were studied. The structurewas observed with the use of X-ray diffraction (XRD), scanning electronmicroscopy (SEM), atomic force microscopy (AFM) and confocal microscopy methods. The obtained results showed that ceramic is porous. Two phase transitionswere determinedwith the use of DSC measurements. The linear and nonlinear ac...
-
Investigation of Liquid–Gas Flow in a Horizontal Pipeline Using Gamma-Ray Technique and Modified Cross-Correlation
PublicationThis article presents the application of the radioisotope absorption method in the study of two-phase water–air flow in a horizontal pipe. The measurement principle and the test stand are briefly described. The main part of the article presents the signal analysis methods applied to data obtained from scintillation detectors. Because these signals are mostly stochastic waveforms, they were analyzed statistically using the cross-correlation...
-
Multi-Criteria Approach in Multifunctional Building Design Process
PublicationThe paper presents new approach in multifunctional building design process. Publication defines problems related to the design of complex multifunctional buildings. Currently, contemporary urban areas are characterized by very intensive use of space. Today, buildings are being built bigger and contain more diverse functions to meet the needs of a large number of users in one capacity. The trends show the need for recognition of...
-
Visible light photocatalytic activity of ionic liquid-TiO2 spheres: effect of the ionic liquid's anion structure
PublicationThe effect of the ionic liquid’s (IL) anion type ([BIMIM][X], where X= [Br], [PF6] or [OctSO4]) and content on the morphology, surface properties and photoactivity of TiO2 obtained by solvothermal method has been systematically investigated. Our results revealed that the presence of [Br], [OctSO4] anions favors formation of anatase phase, while presence of [PF6] anion causes formation of mixture of anatase and Ti(OH)PO4 phases....
-
Improving the Accuracy in Sentiment Classification in the Light of Modelling the Latent Semantic Relations
PublicationThe research presents the methodology of improving the accuracy in sentiment classification in the light of modelling the latent semantic relations (LSR). The objective of this methodology is to find ways of eliminating the limitations of the discriminant and probabilistic methods for LSR revealing and customizing the sentiment classification process (SCP) to the more accurate recognition of text tonality. This objective was achieved...
-
Budowa i sterowanie układu równoważenia napięć w obwodziepośredniczącym czteropoziomowego przekształtnika 4l-DCC
PublicationW artykule opisano budowę nowego układu równoważenia napięć w obwodzie pośredniczącym czteropoziomowego przekształtnika4L-DCC (ang. Four Level Diode Clamped Converter) oraz zaproponowano dwa alternatywne algorytmy modulacji szerokości impulsów - modulacjęPD-PWM (ang. Phase Disposition PWM) oraz PO-PWM (ang. Phase Opposition PWM). Zawarto rozważania dotyczące realizacji układu regulacjinapięć kondensatorów obwodu pośredniczącego.
-
Computer-aided Analysis of Induced Sheath Voltages in High Voltage Power Cable System
PublicationThis paper concerns the effect of configuration of high voltage power cables on induced voltages in their metallic sheaths. One, two or three cables per phase and phase sequence of the cables are considered. Computing of the voltages was performed for a normal operation and in case of earth fault. Various ways of the sheaths bonding are considered as well. Shock hazard and voltage stress of non-metallic outer sheath of cables are...
-
New Procedures for Control of Industrial Effluents Treatment Processes
PublicationThis work presents the procedures for monitoring volatile organic compounds during treatment of industrial effluents. The investigation was carried out for a specific effluent—caustic effluent from bitumen production. The developed procedures enable more detailed control of the effectiveness of wastewater treatment than standard procedures. Caustic effluents from bitumen production have a complex physicochemical form and consist...
-
A distillery by-product as an external carbon source for enhancing denitrification in mainstream and sidestream treatment processes
PublicationThe use of fusel oil as an 'alternative' carbon source for denitrification in the mainstream and sidestream treatment processes was studied. Research comprised two kinds of batch experiments as well as acclimation of process biomass to external carbon sources. In the conventional nitrate utilization rate (NUR) measurements (one-phase experiments with non-acclimated biomass), the NUR with fusel oil was 1.4-1.7 g N/(kg VSS•h which...
-
Optimization of liquid chromatographic separation of pharmaceuticals within green analytical chemistry framework
PublicationThe contribution is aimed at the development of methodology that allows to consider green analytical chemistry criteria during optimization of liquid chromatographic separation with design of experiment. The objectives of the optimization are maximization of peak areas of five non-steroid anti-inflammatory drugs, maximization of resolution between peaks, with simultaneous shortening of chromatographic separation time and minimization...
-
Thickness and structure change of titanium (IV) oxide thin films synthesized by the sol–gel spin coating method
PublicationTitanium dioxide is a well-known material in nanotechnology, while it provides new opportunities due to its interesting properties, for example, as a semiconductor with a quite significant forbidden band gap energy of 3.2 eV. In this study, thin films of titanium dioxide (TiO2) were synthesized in amorphous and crystallographic systems using the sol–gel process. Atomic Force Microscopy (AFM), Raman spectroscopy and X-ray diffraction...
-
Determination of dryout localization using a five-equation model of annular flow for boiling in minichannels
PublicationDetailed studies have suggested that the critical heat flux in the form of dryout in minichannels occurs when the combined effects of entrainment, deposition, and evaporation of the film make the film flow rate go gradually and smoothly to zero. Most approaches so far used the mass balance equation for the liquid film with appropriate formulations for the rate of deposition and entrainment respectively. It must be acknowledged...
-
Detailed experimental investigations on frictional pressure drop of R134a during flow boiling in 5 mm diameter channel: The influence of acceleration pressure drop component =Études expérimentales détaillées sur la chute de pression frictionnelle du R134a lors de l'ébullition en écoulement dans un canal de 5 mm de diamètre : influence de la composante d'accélération de la chute de pression
PublicationThis article presents detailed two-phase diabatic pressure drop data for refrigerant R134a at a saturation pressure of 5.5 bar corresponding to the saturation temperature of 19.4 °C. Study cases have been set for a mass flux varying from 100 to 500 kg m−2 s−1. The obtained data are used as a validation of the void fraction literature models, a set of graphs shows comparisons, for a representative set of experimental conditions,...
-
Preparation and characterisation of iron substituted Mn1.7Cu1.3-xFexO4 spinel oxides (x = 0, 0.1, 0.3, 0.5)
PublicationSpinel oxides with the general formula Mn1.7Cu1.3-xFexO4 (x= 0, 0.1, 0.3, 0.5) were prepared and evaluated in this work for their properties at high temperatures. The effect of partially substituting Cu by Fe has not been studied so far for this group of materials and is thus evaluated in this work. Mn1.7Cu1.3-xFexO4 powders were synthesised by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical...
-
New bulk liquid membrane oscillator composed of two coupled oscillators with diffusion-mediated physical coupling
PublicationA new type of bulk liquid membrane system, which represents the first example of a bulk liquid membrane oscillator characterised by the presence of two coupled oscillators, is described. When the benzyldimethyltetradecylammonium chloride surfactant undergoes an oscillatory mass transfer through a nitromethane liquid membrane, a new liquid layer (phase X) appears between the membrane and the acceptor phase. Kinetic analysis provides...
-
Formation of intermetallic compounds in the solid-liquid composites of the Ga-Ni system
PublicationThe processes of formation of intermetallic compounds in the composite system of liquid gallium-nickel powder by the methods of x-ray diffraction, scanning electron microscopy and differential thermal analysis have been studied. A change in the phase composition was discovered and the influence of thermal treatment of the composites under investigation on the phase formation processes was analyzed. The mechanism of gallium enriched...
-
Troubleshooting of the determination of bisphenol A at ultra-trace levels by liquid chromatography and tandem mass spectrometry
PublicationDetermination of trace amounts of bisphenol A (BPA) may cause problems mainly related to the presence of BPA in solvents (even in LC-MS grade), laboratory vessels, and plastic equipment used for sample preparation. Variable and sometimes significant amounts of BPA present in the background cause problems in obtaining good repeatability of measurements at the ultra-trace levels. Such observations (i.e., poor repeatability of results)...
-
Mask Detection and Classification in Thermal Face Images
PublicationFace masks are recommended to reduce the transmission of many viruses, especially SARS-CoV-2. Therefore, the automatic detection of whether there is a mask on the face, what type of mask is worn, and how it is worn is an important research topic. In this work, the use of thermal imaging was considered to analyze the possibility of detecting (localizing) a mask on the face, as well as to check whether it is possible to classify...
-
The role of biodegradable particulate and colloidal organic compounds in biological nutrient removal activated sludge systems
PublicationThe efficiency of denitrification and enhanced biological phosphorus removal in biological nutrient removal activated sludge systems is strongly dependent on the availability of appropriate carbon sources. Due to high costs of commercial compounds (such as methanol, ethanol, acetic acid, etc.) and acclimation periods (usually) required, the effective use of internal substrates is preferred. The aim of this study was to determine...
-
Recent advances on SOA formation in indoor air, fate and strategies for SOA characterization in indoor air - A review
PublicationRecent studies proves that indoor air chemistry differs in many aspects from atmospheric one. People send up to 90 % of their life indoors being exposed to pollutants present in gas, particle and solid phase. Particle phase indoor is composed of particles emitted from various sources, among which there is an indoor source – secondary chemical reactions leading to formation of secondary organic aerosol (SOA). Lately, researchers'...
-
Occurrence of Surface Active Agents in the Environment
PublicationDue to the specific structure of surfactants molecules they are applied in different areas of human activity (industry, household). After using and discharging from wastewater treatment plants as effluent stream, surface active agents (SAAs) are emitted to various elements of the environment (atmosphere, waters, and solid phases), where they can undergo numerous physic-chemical processes (e.g., sorption, degradation) and freely...
-
Morphology changes in Fe-Cr porous alloys upon high-temperature oxidation quantified by X-ray tomographic microscopy
PublicationThe effect of high-temperature oxidation at 850 C (10 h, 30 h, 100 h) and 900 C (10 h) on porous (30 % porosity) ferritic stainless steel (Fe22Cr) has been investigated using synchrotron tomographic microscopy, which allowed for visualisation, separation and quantitative analysis of the metallic core, closed pores, open pores and oxide scale phase. The same regions within the samples were investigated before and after oxidation...
-
Calculating the Partition Coefficients of Organic Solvents in Octanol/Water and Octanol/Air
PublicationPartition coefficients define how a solute is distributed between two immiscible phases at equilibrium. The experimental estimation of partition coefficients in a complex system can be an expensive, difficult, and time-consuming process. Here a computational strategy to predict the distributions of a set of solutes in two relevant phase equilibria is presented. The octanol/water and octanol/air partition coefficients are predicted...
-
Numerical Study of Turbulent Flow and Heat Transfer of Nanofluids in Pipes
PublicationIn this work, Nusselt number and friction factor are calculated numerically for turbulent pipe flow (Reynolds number between 6000 and 12000) with constant heat flux boundary condition using nanofluids. The nanofluid is modelled with the single-phase approach and the simulation results are compared with experimental data. Ethylene glycol and water, 60:40 EG/W mass ratio, as base fluid and SiO2 nanoparticles are used as nanofluid...
-
Analytical applications and physicochemical properties of ionic liquid-based hybrid materials: A review
PublicationIonic liquids with their unique properties found so far numerous analytical applications. Among them ionic liquids immobilized on the surface or within the pores of a solid support were successfully utilized in extraction techniques dedicated to preconcentration of the analytes from food, environmental and biological samples. In this review we focus on comprehensive summarizing of available literature data on the examples of ionic...