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Comparing some convolution-based methods for creation of surround sound
PublikacjaW referacie przedstawiono eksperymenty związane z symulacją dźwięku dookólnego w sali koncertowej. W tym celu wykorzystano splot odpowiedzi impulsowej z danego wnętrza (wielokanałowe nagrania odpowiedzi impulsowej) z nagraniami z komory bezechowej. Uzyskany w ten sposób sygnał został następnie przypisany do odpowiednich kanałów w systemie dookólnym. Uzyskane w ten sposób nagrania były następnie porównywane w testach subiektywnych...
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Comparative analysis of switched reluctance motor control algorithms
PublikacjaПредмет исследования. Развитие микропроцессорной техники и силовой электроники позволило создавать недорогие и эффективные системы управления различными электромеханическими объектами, которые ранее широко не использовались из-за сложности управления. К таким устройствам можно отнести вентильно-индукторные электрические машины. Данные машины широко применяются в различных практических разработках, например, в тяговом электроприводе,...
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Comparative analysis of switched reluctance motor control algorithms
PublikacjaПредмет исследования. Развитие микропроцессорной техники и силовой электроники позволило создавать недорогие и эффективные системы управления различными электромеханическими объектами, которые ранее широко не использовались из-за сложности управления. К таким устройствам можно отнести вентильно-индукторные электрические машины. Данные машины широко применяются в различных практических разработках, например, в тяговом электроприводе,...
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ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT
PublikacjaThe possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections...
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Creating a Realible Music Discovery and Recomendation System
PublikacjaThe aim of this paper is to show problems related to creating a reliable music dis-covery system. The SYNAT database that contains audio files is used for the purpose of experiments. The files are divided into 22 classes corresponding to music genres with different cardinality. Of utmost importance for a reliable music recommendation system are the assignment of audio files to their appropriate gen-res and optimum parameterization...
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Distortion of speech signals in the listening area: its mechanism and measurements
PublikacjaThe paper deals with a problem of the influence of the number and distribution of loudspeakers in speech reinforcement systems on the quality of publicly addressed voice messages, namely on speech intelligibility in the listening area. Linear superposition of time-shifted broadband waves of a same form and slightly different magnitudes that reach a listener from numerous coherent sources, is accompanied by interference effects...
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Bitumen-Based Poroelastic Pavements: Successful Improvements and Remaining Issues
PublikacjaThis article presents the development process of designing and testing poroelastic pavement based on highly polymer-modified bitumen. Poroelastic wearing course was composed of mineral and rubber aggregate mixed with highly polymer-modified bitumen, in contrast to previous trials, during which polyurethane resins were mainly used as binder, which led to several serious technological problems concerning difficult production, insufficient...
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Experimental investigations on the mechanical properties and damage detection of carbon nanotubes modified crumb rubber concrete
PublikacjaThis study presents a modified crumb rubber (MCR) concrete design mix reinforced with multi-walled carbon nanotubes (MWCNTs), mechanical characterization, and cracking monitoring using the acoustic emission (AE) technique. The results showed that the bridging effect of MWCNTs and MCR in the concrete mix mitigated the shortcomings of MWCNT-MCR concrete and improved the flexural and compressive strengths by 18.3% and 26.5%, respectively,...
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Examining Feature Vector for Phoneme Recognition / Analiza parametrów w kontekście automatycznej klasyfikacji fonemów
PublikacjaThe aim of this paper is to analyze usability of descriptors coming from music information retrieval to the phoneme analysis. The case study presented consists in several steps. First, a short overview of parameters utilized in speech analysis is given. Then, a set of time and frequency domain-based parameters is selected and discussed in the context of stop consonant acoustical characteristics. A toolbox created for this purpose...
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System oceny efektywności użytkowania aparatów słuchowych
PublikacjaCelem rozprawy jest opracowanie metody oceny efektywności protezowania słuchu przy użyciu aparatów słuchowych, która pozwoli w łatwy sposób poddawać ocenie korzyść z użytkowania protez słuchowych w najbardziej typowych sytuacjach akustycznych. Przedstawiono genezę podjętych badań i na tej podstawie zaproponowano cele i tezy rozprawy doktorskiej. W pracy w pierwszej kolejności zawarto przegląd dotyczący rodzajów ubytku słuchu i...
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Thermophysical study of the binary mixtures of triethyl phosphate with N-methylformamide, N,N-dimethylformamide and N,N-dimethylacetamide – Experimental and theoretical approach
PublikacjaDensities at (293.15, 298.15, 303.15 and 308.15) K, and viscosities and ultrasonic velocities at 298.15 K of binary liquid mixtures of triethyl phosphate with N-methylformamide, N,N-dimethylformamide and N,N-dimethylacetamide have been measured over the entire range of composition at p = 0.1 MPa. From the experimental data, values of excess molar volume, excess isentropic compressibility, viscosity deviation and excess Gibbs energy...
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Identification of synergistic and antagonistic actions of environmental pollutants: Bisphenols A, S and F in the presence of DEP, DBP, BADGE and BADGE·2HCl in three component mixtures
PublikacjaEcosystems are facing increased pressure due to the emission of many classes of emerging contaminants. However, very little is known about the interactions of these pollutants, such as bisphenols (BPs), plasticizers or pharmaceuticals. By employing bioluminescent bacteria (Microtox assay), we were able to define interactions between selected emerging pollutants (namely BPA, BPS, BPF, BADGE, BADGE·2HCl, DEP, DBP) in ternary mixtures, at...
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Sensitivity analysis based on non-intrusive regression-based polynomial chaos expansion for surgical mesh modelling
PublikacjaThe modelling of a system containing implants used in ventral hernia repair and human tissue suffers from many uncertainties. Thus, a probabilistic approach is needed. The goal of this study is to define an efficient numerical method to solve non-linear biomechanical models supporting the surgeon in decisions about ventral hernia repair. The model parameters are subject to substantial variability owing to, e.g., abdominal wall...
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MICROCOMPASS FOR SAFE SEA NAVIGATION
PublikacjaThis paper presents the results of design microcompass for safe sea navigation where navigation, electronic, programming knowledge was joined to make more safe sea navigation. In first part of article presents navigation tools which using in practise. Article underlines that mostly satellite system is used to make navigation, but recommends traditional navigation method like alternative to determinate position in case of breakdown...
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Investigation of vortex assisted magnetic deep eutectic solvent based dispersive liquid–liquid microextraction for separation and determination of vanadium from water and food matrices: Multivariate analysis
PublikacjaA new and simple vortex assisted magnetic deep eutectic solvent dispersive liquid–liquid microextraction procedure (VA-MDES-DLLME) was developed for the determination of vanadium (V) in food and water samples by flame atomic absorption spectrometry (FAAS). In the extraction medium, a bis(acetylpivalylmethane) ethylenediimine (H2APM2en) was used for the complexation of V(V) in sample solution at pH 6. The VA-MDES-DLLME was optimized...
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The electrical, morphological and optical properties of heavily boron-doped diamond sheets as a function of methane concentration in the gas phase
PublikacjaBoron-doped diamonds (BDD) are known for their excellent properties such as high thermal conductivity, high mobility, low absorption in visible light, and biocompatibility. In this work, we investigated the electrical, morphological and optical properties of heavily boron-doped diamond thin sheets as a function of methane concentration in the gas phase. Free-standing diamond sheets were fabricated using a microwave plasma-assisted...
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Probing Local Structural Changes by Sharp Luminescent Infrared Nanophosphor for Application in Light-Emitting Diodes
PublikacjaCr3+-doped infrared phosphors are promising candidates for next-generation phosphor-converted infrared light-emitting diodes (LEDs) because they can, in principle, tune and convert the luminescence spectra from an LED chip. However, most studies focus on broad-band Cr3+-doped phosphors, and the control mechanism of Cr3+-doped phosphors with sharp line emissions remains ambiguous. Here, we report LiGa5(1–x)Al5xO8:Cr3+ phosphors...
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Numerical analysis of the ostiomeatal complex aeration using the CFD method
PublikacjaWe aimed to analyse ostiomeatal complex (OMC) aeration using the computational fluid dynamics (CFD) method of simulation based on human craniofacial computed tomography (CT) scans. The analysis was based on CT images of 2 patients: one with normal nose anatomy and one with nasal septal deviation (NSD). The Reynolds-Average Simulation approach and turbulence model based on linear eddy viscosity supplemented with the two-equation...
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Enhanced Toxicity of Bisphenols Together with UV Filters in Water: Identification of Synergy and Antagonism in Three-Component Mixtures
PublikacjaContaminants of emerging concern (CEC) localize in the biome in variable combinations of complex mixtures that are often environmentally persistent, bioaccumulate and biomagnify, prompting a need for extensive monitoring. Many cosmetics include UV filters that are listed as CECs, such as benzophenone derivatives (oxybenzone, OXYB), cinnamates (2-ethylhexyl 4-methoxycinnamate, EMC) and camphor derivatives (4-methylbenzylidene-camphor,...
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Bisphenols (A, S, and F) affect the basic hormonal activity determined for pharmaceuticals – Study of Saccharomyces cerevisiae
PublikacjaPharmaceuticals and analogs of bisphenol A (BPA) are increasingly threatening environmental pollutants. In this study, mixtures of selected pharmaceuticals (diclofenac sodium salt, chloramphenicol, oxytetracycline hydrochloride, fluoxetine hydrochloride, estrone, ketoprofen, progesterone, gemfibrozil and androstenedione) were prepared with BPA and its two analogs (namely, bisphenols F and S) at such ratios to reflect environmentally...
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Photocatalytic decolourization of Rhodamine-B dye by visible light active ZIF-8/BiFeO3 composite
PublikacjaIn this work, preparation of ZIF-8 supported BiFeO3 photocatalyst by ultrasound cavitation technique was reported. The synthesized materials were characterized using solid UV absorption spectroscopy, Raman Spectroscopy, and SEM. The catalytic function of synthesized photocatalyst under ultraviolet and visible light was examined for the decolourization of Rhodamine-B (Rh-B) dye. To understand the action of the photocatalyst on Rh-B...
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Low cost set-up for supercapacitors parameters evaluation
PublikacjaSupercapacitors are capable to store relatively high amount of energy comparing to its mass. Growing number of these devices applications requires development of new testing methods. Standard methods of evaluation of supercapacitor parameters, as cycling voltammetry, CV, galvanostatic cycling with potential limitation, GCPL, impedance measurements, require equipment of high cost...
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A spice equivalent circuit for modeling the performance of dual frequency echo-sounder
PublikacjaThe paper presents novel network equivalent circuit of piezoceramic circular disc transducers that takes into account thickness and radial mode of vibrations. The starting point of the analysis is 4-port description of circular disc element representing the solution of wave equation set in radial and thickness directions. The approximate solution for harmonic case is represented in the form of 4x4 matrix, which is synthesised and...
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Data Compression in Ultrasonic Network Communication via Sparse Signal Processing
PublikacjaThis document presents the approach of using compressed sensing in signal encoding and information transferring within a guided wave sensor network, comprised of specially designed frequency steerable acoustic transducers (FSATs). Wave propagation in a damaged plate was simulated using commercial FEM-based software COMSOL. Guided waves were excited by means of FSATs, characterized by the special shape of its electrodes, and modeled...
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An audio-visual corpus for multimodal automatic speech recognition
Publikacjareview of available audio-visual speech corpora and a description of a new multimodal corpus of English speech recordings is provided. The new corpus containing 31 hours of recordings was created specifically to assist audio-visual speech recognition systems (AVSR) development. The database related to the corpus includes high-resolution, high-framerate stereoscopic video streams from RGB cameras, depth imaging stream utilizing Time-of-Flight...
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Multisensor System for the Protection of Critical Infrastructure of Seaport
PublikacjaThere are many separated infrastructural objects within a harbor area that may be considered “critical”, such as gas and oil terminals or anchored naval vessels. Those objects require special protection, including security systems capable of monitoring both surface and underwater areas, because an intrusion into the protected area may be attempted using small surface vehicles (boats, kayaks, rafts, floating devices with weapons...
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Dynamic Bayesian Networks for Symbolic Polyphonic Pitch Modeling
PublikacjaSymbolic pitch modeling is a way of incorporating knowledge about relations between pitches into the process of an- alyzing musical information or signals. In this paper, we propose a family of probabilistic symbolic polyphonic pitch models, which account for both the “horizontal” and the “vertical” pitch struc- ture. These models are formulated as linear or log-linear interpo- lations of up to fi ve sub-models, each of which is...
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Evaluation of Medical Staff Satisfaction for Workplace Architecture in Temporary COVID-19 Hospital: A Case Study in Gdańsk, Poland
PublikacjaThis article analyses the architecture that was used in the temporary AmberExpo hospital in Gdańsk, Poland which was installed during the COVID-19 pandemic. The construction of this type of facility is often based on experimental approaches, aimed at caring for patients suffering from an infectious disease in emergency conditions. In order to assess the level of employee satisfaction with the architectural and technical elements...
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Shales Leaching Modelling for Prediction of Flowback Fluid Composition
PublikacjaThe object of the paper is the prediction of flowback fluid composition at a laboratory scale, for which a new approach is described. The authors define leaching as a flowback fluid generation related to the shale processing. In the first step shale rock was characterized using X-ray fluorescence spectroscopy, X-ray diractometry and laboratory analysis. It was proven that shale rock samples taken from the selected sections of horizontal...
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The Proposition of an Automated Honing Cell with Advanced Monitoring
PublikacjaHoning of holes allows for small shape deviation and a low value of a roughness profile parameter, e.g., Ra parameter. The honing process heats the workpiece and raises its temperature. The increase in temperature causes thermal deformations of the honed holes. The article proposes the construction of a honing cell, containing in addition to CNC honing machine: thermographic camera, sound intensity meter, and software for collecting...
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Seafloor characterisation using multibeam sonar echo signal processing and image analysis
PublikacjaThe authors propose the approach to multibeam seafloor characterisation which relies on the combined, concurrent use of two different techniques of multibeam sonar data processing. The first one is based on constructing the grey-level sonar images of seabed using the echoes received in the consecutive beams. Then, the parameters describing the local region of sonar image, namely, the local standard deviation of a grey level, and...
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High-temperature Corrosion of ~ 30 Pct Porous FeCr Stainless Steels in Air: Long-Term Evaluation Up to Breakaway
PublikacjaIn this work, a long-term (up to 6000 hours) corrosion evaluation of three porous (~ 30 pct of initial porosity) ferritic iron-chromium alloys with different Cr contents (20, 22, and 27 wt pct of Cr) was carried out at 600 C, 700 C, 800 C, and 900 C in air. Mass gain measurements and SEM analyses revealed that at temperatures above 600 C, all alloys exhibit breakaway corrosion, whereas at 600 C, none of the alloys were heavily...
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New procedure for the control of the treatment of industrial effluents to remove volatile organosulfur compounds
PublikacjaWe present a new procedure for the determination of volatile organosulfur compounds in samples of industrial effluents using dispersive liquid–liquid microextraction and gas chromatography with flame photometric detection. Initially, the extraction parameters were optimized. These included: type and volume of extraction solvent, volume of disperser solvent, salting out effect, pH, time and speed of centrifugation as well as extraction...
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Reliability and Validity of Optoelectronic Method for Biophotonical Measurements
PublikacjaReliability and validity of measurements is of utmost importance when assessing measuring capability of instruments developed for research. In order to perform an experiment which is legitimate, used instruments must be both reliable and valid. Reliability estimates the degree of precision of measurement, the extent to which a measurement is internally consistent. Validity is the usefulness of an instrument to perform accurate...
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Application of chemometric modeling for ionic liquid-based ultrasonic-assisted dispersive liquid-liquid microextraction: Analysis of fosetyl-aluminum in fruit and vegetable samples
PublikacjaThis manuscript presents a new method for selective extraction and determination of fosetyl-aluminum in fruits and vegetable samples based on ultrasonic-assisted dispersive liquid-liquid microextraction method using ionic liquids (IL-UA-DLLME). A UV-Visible spectrophotometer was used for detection and quantification. Plants used for sample collection were grown under controlled conditions in a greenhouse. Central composite design...
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Natural deep eutectic solvent based ultrasound assisted liquid-liquid micro-extraction method for methyl violet dye determination in contaminated river water
PublikacjaSimple and green natural deep eutectic solvent (NADES) based ultrasound assisted liquid-liquid micro-extraction (UA-LLME) method was developed for extraction and determination of methyl violet dye in contaminated river water samples using UV/Vis spectrophotometry. Choline chloride - decanoic acid based natural deep eutectic solvent was used for extraction. Important analytical parameters like pH, deep eutectic solvent volume/phase...
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Maxillary sinus aeration analysis using computational fluid dynamics
PublikacjaThe maxillary sinus aeration using the computational fluid dynamics (CFD) method based on individual adult patients’ computed tomography (CT) scans were analyzed. The analysis was based on CT images of 4 patients: one with normal nose anatomy and three with nasal septal deviation (NSD) and concha bullosa (CB). The CFD simulation was performed using the Reynolds-Average Simulation approach and turbulence closure based on linear...
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Spectrum Sensing Based on Hybrid Spectrum Handoff in Cognitive Radio Networks
PublikacjaThe rapid advancement of wireless communication combined with insufficient spectrum exploitation opens the door for the expansion of novel wireless services. Cognitive radio network (CRN) technology makes it possible to periodically access the open spectrum bands, which in turn improves the effectiveness of CRNs. Spectrum sensing (SS), which allows unauthorized users to locate open spectrum bands, plays a fundamental part in CRNs....
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Multi-transformer primary-side regulated flyback converter for supplying isolated IGBT and MOSFET drivers
PublikacjaThis paper presents primary-side voltage regulated multi-transformer quasi-resonant flyback converter (MTFC) for supplying isolated power switch drivers. The proposed topology offers distinct advantages over frequently used flyback converter possessing one high frequency transformer with isolated multiple outputs. Particularly, when a large number of separate dc supply units is required, then MTFC enables improved regular distribution...
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Design Analysis of Micro Gas Turbines in Closed Cycles
PublikacjaThe problems faced by designers of micro-turbines are connected with a very small volume flow rate of working media which leads to small blades’ height and high rotor speed. In the case of gas turbines this limitation can be overcome by the application of a closed cycle with very low pressure at the compressor inlet (lower than atmospheric pressure). In this way we may apply a micro gas turbine unit of accepted efficiency to work...
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Mutual Interaction between Temperature and DO Set Point on AOB and NOB Activity during Shortcut Nitrification in a Sequencing Batch Reactor in Terms of Energy Consumption Optimization
PublikacjaRecently, many wastewater treatment plants (WWTPs) have had to deal with serious problems related to the restrictive requirements regarding the euent quality, as well as significant energy consumption associated with it. In this situation, mainstream deammonification and/or shortened nitrification-denitrification via nitrite (so-called “nitrite shunt”) is a new promising strategy. This study shows the mechanisms and operating conditions...
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Characterization of glucoamylase immobilized on magnetic nanoparticles
PublikacjaMagnetic support was prepared by precipitation from an alkaline solution of divalent and trivalent iron ions and subsequently was modified with 3-aminopropyltriethoxysilane. FTIR analysis showed existence of a new Si-O-Fe bond in obtained particles. Scanning electronic microscopy images shows that the nanoparticles of all samples have particle size below 30 nm. Glucoamylase AMG 300L was immobilized onto the modified magnetic support...
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From tryptophan to novel mitochondria-disruptive agent, synthesis and biological evaluation of 1,2,3,6-tetrasubstituted carbazoles
PublikacjaMitochondrial targeting plays an important role in anticancer therapy. The Mn(III)-promoted cyclization of 5- (1H-indol-3-yl)-3-oxopentanoic acid allow to obtain novel substituted carbazole derivatives that can act as mitochondria-disruptive agents. The starting materials used for the synthesis of these new aminocarbazoles are oxopentanoate derivatives of tryptophan. The scope and limitation of this method of synthesis are determined...
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Modeling of Electrified Transportation Systems Featuring Multiple Vehicles and Complex Power Supply Layout
PublikacjaThe paper proposes a novel approach to modeling electrified transportation systems. The proposed solution reflects the mechanical dynamics of vehicles as well as the distribution and losses of electric supply. Moreover, energy conversion losses between the mechanical and electrical subsystems and their bilateral influences are included. Such a complete model makes it possible to replicate, e.g., the impact of voltage drops on vehicle...
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Increasing efficiency of technological process by limiting impact of corrosive environment on operation of spiral classifiers
PublikacjaMost of the technological operations related to the preparation of the output to be enriched and to the production of the final copper concentrate take place with the use of water environment. Water management, besides using innovative technical and technological solutions, is a significant factor in the whole copper ore enrichment process. Mine water resources and surface water of the tailing pond named "Żelazny Most" are the...
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Combination of air-dispersion cathode with sacrificial iron anode generating Fe2+Fe3+2O4 nanostructures to degrade paracetamol under ultrasonic irradiation
PublikacjaIn the present study, ultrasound (US) was coupled with an electrochemical process (ECP) consisting of a novel cathode of carbon cloth (CC)-carbon black (CB) as the nano-composite air-dispersion cathode (NADC) for the degradation of paracetamol (APAP) in an aquatic medium. The NADC favored in situ production of H2O2 by the cathodic reduction. The implementation of iron sacrificial anode instead of dimensionally stable anodes resulted...
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Microbe Cultivation Guidelines to Optimize Rhamnolipid Applications
PublikacjaIn the growing landscape of interest in natural surfactants, selecting the appropriate one for specific applications remains challenging. The extensive, yet often unsystematized, knowledge of microbial surfactants, predominantly represented by rhamnolipids (RLs), typically does not translate beyond the conditions presented in scientific publications. This limitation stems from the numerous variables and their interdependencies...
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Synteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu
PublikacjaSynteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu stanowi cel niniejszej monografii. Praca zawiera podstawowe informacje na temat modelowania układu napędowego z maszyną indukcyjną klatkową zasilaną z falownika prądu. Przedstawiono informacje na temat linearyzacji nieliniowych obiektów. Na pod-stawie metody syntezy strukturalnej opracowano nowe transformacje do postaci zmien-nych multiskalarnych,...
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Comparative study on the effectiveness of various types of road traffic intensity detectors
PublikacjaVehicle detection and speed measurements are crucial tasks in traffic monitoring systems. In this work, we focus on several types of electronic sensors, operating on different physical principles in order to compare their effectiveness in real traffic conditions. Commercial solutions are based on road tubes, microwave sensors, LiDARs, and video cameras. Distributed traffic monitoring systems require a high number of monitoring...
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ENERGY ANALYSIS OF THE PROPULSION SHAFT FATIGUE PROCESS IN A ROTATING MECHANICAL SYSTEM PART II IDENTIFICATION STUDIES – DEVELOPING THE FATIGUE DURABILITY MODEL OF A DRIVE SHAFT
PublikacjaThe article presents a continuation of research carried out concerning identification of energy consequences of mechanical fatigue within a propeller shaft in a rotating mechanical system, while working under conditions of the loss of the required alignment of shaft lines. Experimental research was carried out on a physical model reflecting a full-sized real object: i.e., the propulsion system of the ship. It is proven, by means...