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MgPdSb─An Electron-Deficient Half-Heusler Phase
PublicationThe half-Heusler family consists of many semiconducting intermetallic compounds, virtually all of them having a valence electron count (VEC) of 18. We have studied an electron-deficient (VEC = 17) phase MgPdSb and its Pd-stuffed variant MgPd1.25Sb. The cubic F4̅3m crystal structure was confirmed by the Rietveld refinement of powder X-ray diffraction (XRD) data. The lattice parameter is a = 6.284 and 6.335 Å for MgPdSb and MgPd1.25Sb,...
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Analysis of the harmonic structure of the vowel /a/ taking into account the age and gender of the speaker
PublicationSound waves are disturbances propagating through an elastic medium that, upon reaching the ear, elicit auditory sensations. Sounds generated by the surroundings can be captured by a transducer (microphone), which transforms them into an electrical signal. The signal from the microphone is then transmitted to a computer, where software allows for the extraction and analysis of individual tones. This process enables the description...
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Pesticides in the Environment
PublicationApplied all over the world, pesticides are some of the most dangerous pollutants of the environment becauseof their mobility and ability to accumulate in the environment and their consequent long-term adverseeffects on living organisms in general and human health in particular. For these reasons, it is essential tomonitor and analyze pesticide residues in the environment. This entry discusses the classification of pesticidesas...
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Monitoring and analytics of semivolatile organic compounds (SVOCs) in indoor air
PublicationThis paper reviews literature information on the behaviour of semivolatile organic compounds (SVOCs) in the indoor environment, as well as the most likely emission sources. The consecutive stages of analytical procedures used for monitoring SVOCs in indoor environments are described. The most common approaches used for collecting samples from the gas and particulate phases are mentioned. The paper discusses and compares various...
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Determination of pesticide residues in fruits and vegetables using QuEChERS sample preparation method
PublicationThe intensive development of agriculture means that more and more toxic organic and inorganic compounds are entering the environment. Because of their widespread use, environmental stability, selective toxicity and bioaccumulative capability, pesticides belong to the most hazardous substances contaminating the environment. They are particularly dangerous in fruits and vegetables, because they are one of the reasons why people are...
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The Hough transform in the classification process of inland ships
PublicationThis article presents an analysis of the possibilities of using image processing methods for feature extraction that allows kNN classification based on a ship’s image delivered from an on-water video surveillance system. The subject of the analysis is the Hough transform which enables the detection of straight lines in an image. The recognized straight lines and the information about them serve as features in the classification...
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Accelerated simulation-driven design optimisation of compact couplers by means of two-level space mapping
PublicationIn this study, the authors discuss a robust and efficient technique for rapid design of compact couplers. The approach exploits two-level space mapping (SM) correction of an equivalent circuit model of the coupler structure under design. The first SM layer (local correction) is utilised to ensure good matching between the equivalent circuit and the electromagnetic model at the component level. Subsequent global correction allows...
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Method for the determination of carboxylic acids in industrial effluents using dispersive liquid-liquid microextraction with injection port derivatization gas chromatography–mass spectrometry
PublicationThe paper presents a new method for the determination of 15 carboxylic acids in samples of postoxidative effluents from the production of petroleum bitumens using ion-pair dispersive liquid-liquid microextraction and gas chromatography coupled to mass spectrometry with injection port derivatization. Several parameters related to the extraction and derivatization efficiency were optimized. Under optimized experimental conditions,the...
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Pilot Testing of Developed Multimodal Biometric Identity Verification System
PublicationThe bank client identity verification system developed in the course of the IDENT project is presented. The total number of five biometric modalities including: dynamic signature proofing, voice recognition, face image verification, face contour extraction and hand blood vessels distribution comparison have been developed and studied. The experimental data were acquired employing multiple biometric sensors installed at engineered...
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Multimodal system for diagnosis and polysensory stimulation of subjects with communication disorders
PublicationAn experimental multimodal system, designed for polysensory diagnosis and stimulation of persons with impaired communication skills or even non-communicative subjects is presented. The user interface includes an eye tracking device and the EEG monitoring of the subject. Furthermore, the system consists of a device for objective hearing testing and an autostereoscopic projection system designed to stimulate subjects through their...
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Decisional DNA (DDNA) Based Machine Monitoring and Total Productive Maintenance in Industry 4.0 Framework
PublicationThe entire manufacturing spectrum is transforming with the advent of Industry 4.0. The features of Set of Experience Knowledge Structure (SOEKS) and Decisional DNA (DDNA) were utilized for developing Virtual Engineering Objects (VEO), Virtual Engineering Process (VEP) and Virtual Engineering Factory (VEF), which in turn facilitate the creation of smart factories. In this study, DDNA based Machine Monitoring for Total Maintenance...
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Pursuing the Deep-Learning-Based Classification of Exposed and Imagined Colors from EEG
PublicationEEG-based brain-computer interfaces are systems aiming to integrate disabled people into their environments. Nevertheless, their control could not be intuitive or depend on an active external stimulator to generate the responses for interacting with it. Targeting the second issue, a novel paradigm is explored in this paper, which depends on a passive stimulus by measuring the EEG responses of a subject to the primary colors (red,...
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Problems of Measuring Gas Content in Oil in a Two-Phase Flow: A Review
PublicationIn view of the necessity of measuring the air content in oil in two-phase flows in the context of general industry, a review of the most popular methods of measuring the air content in oil was carried out. This review includes an assessment of their advantages and disadvantages and of whether they meet criteria such as the degree of filling, the size and number of bubbles, verification, the absence of additional pressure drops,...
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Digital phase-location system for marine applications
PublicationThis paper presents concept and implementation of digital phase-location system, designed as a navigational aid for marine applications. Main feature of proposed system is the ability to work in both synchronous mode, with one master station and set of slave stations synchronized with master, and in asynchronous mode with independent clocking of all stations.
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Critical behaviour of the smectic A*–C* phase transition and electroclinic effect of ferroelectric liquid crystals with terphenyl rigid core
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On Kinetic Nature of Hysteresis Phenomena in Stress-Induced Phase Transformations
PublicationA simplest model is developed which demonstrates that hysteresis phenomena in stress-induced phase transformations may have a kinetic nature and follow from the discrepancy between strain rate and characteristic rate of the new phase growth.
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Investigation of solid polymer electrolyte gas sensor with different electrochemical techniques
PublicationIn this work solid polymer electrolyte (SPE) amperometric sulphur dioxide sensor is investigated. Nafion was used as a membrane electrode and 1M sulphuric acid as an internal electrolyte. Sensor response to sulphur dioxide was measured. Besides traditional constant voltage amperometry also different electrochemical techniques were used. Results obtained by these methods are compared.
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Open-Phase Fault Detection Method for Sensorless Five-Phase Induction Motor Drives with an Inverter Output Filter
PublicationThe paper presents the sensorless five-phase induction motor drive implementation with an inverter output filter with third harmonic injection. For the sensorless operation, the required observers are presented for the first and third harmonics with consideration of the inverter output filter. Moreover, the interaction of the observers and the control system is capable to handle a deactivation of one or two phases, which improves...
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CeCu2O4 as a functional layer on solid oxide fuel cells for synthetic biogas reforming
PublicationSolid Oxide Fuel Cells (SOFC) are one of the most promising electrochemical devices, which can convert chemical energy to the electrical energy these days. Their ability to work with different kind of fuel makes them noteworthy. SOFC can work with biogas. The problem arises when solid carbon starts to be deposited in anode. That leads to degradation of fuel cell. Simple solution is to apply catalytic functional layer, which is...
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Investigation of thin perovskite layers between cathode and doped ceria used as buffer layer in solid oxide fuel cells
PublicationIn this paper, thin perovskite layers between cathode material of solid oxide fuel cells and gadolinia-doped ceria buffer layer are investigated. Thin layers made of LaNi0.6Fe0.4O3-δ (LNF), La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), or SrTi0.65Fe0.35O3-δ (STF) were symmetrically deposited by spin coating method from metallo-organic polymer precursors on a Ce0.8Gd0.2O2-δ (CGO) substrate. Porous and about 40-μm-thick LNF cathodes were deposited...
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Influence of the air phase on water flow in dikes
PublicationNumerical models are often used to describe flow and deformation processes occurring in dikes during flood events. Modeling of such phenomena is a challenging task, due to the complexity of the system, consisting of three material phases: soil skeleton, pore water and pore air. Additional difficulties are transient loading caused by variable in time water levels, heterogeneity of the soil or air...
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Electrochemical performance of Co3O4/CeO2 electrodes in H2S/H2O atmospheres in a proton-conducting ceramic symmetrical cell with BaZr0.7Ce0.2Y0.1O3 solid electrolyte
PublicationThe electrochemical performance of Co3O4/CeO2 mixed oxide materials as electrodes, when exposed to H2S/H2O atmospheres, was examined employing a proton conducting symmetrical cell, with BaZr0.7Ce0.2Y0.1O3 (BZCY72) as the solid electrolyte. The impact of temperature (700–850 °C) and H2S concentration (0–1 v/v%) in steam-rich atmospheres (90 v/v% H2O) on the overall cell performance was thoroughly assessed by means of electrochemical...
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Ammonia Gas Sensors: Comparison of Solid-State and Optical Methods
PublicationHigh precision and fast measurement of gas concentrations is important for both understanding and monitoring various phenomena, from industrial and environmental to medical and scientific applications. This article deals with the recent progress in ammonia detection using in-situ solid-state and optical methods. Due to the continuous progress in material engineering and optoelectronic technologies, these methods are among the most...
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A modern solid waste management strategy – the generation of new by-products
PublicationTo benefit the environment and society, EU legislation has introduced a ‘zero waste’ strategy, in which waste material should be converted to resources. Such legislation is supported by the solid waste hierarchy concept, which is a set of priorities in waste management. Under this concept, municipal solid waste plants (MSWPs) should be equipped with sorting and recycling facilities, composting/incineration units and landfill prisms...
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Extended non-linear relations of elastic shells undergoing phase transitions
PublicationThe non-linear theory of elastic shells undergoing phase transitions was proposed by two first authors in J. Elast. 79, 67-86 (2004). In the present paper the theory is extended by taking into account also the elastic strain energy density of the curvilinear phase interface as well as the resultant forces and couples acting along the interface surface curve itself. All shell relations are found from the variational principle of...
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Image Segmentation of MRI image for Brain Tumor Detection
Publicationthis research work presents a new technique for brain tumor detection by the combination of Watershed algorithm with Fuzzy K-means and Fuzzy C-means (KIFCM) clustering. The MATLAB based proposed simulation model is used to improve the computational simplicity, noise sensitivities, and accuracy rate of segmentation, detection and extraction from MR...
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Mobility and bioavailability of mercury in sediments of the southern Baltic sea in relation to the chemical fractions of iron: Spatial and temporal patterns
PublicationMarine sediments play a significant role as reservoirs for mercury (Hg), a bioaccumulative toxic pollutant that poses risks to human and ecosystem health. Iron (Fe) has been recognized as an influential factor in the complexation and bioavailability of Hg in sediments. However, limited studies have investigated the interactions between the chemical fractions of these elements in natural settings. This study aims to examine the...
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Thermodynamic Efficiency of an Advanced 4th Generation VHTR Propulsion Engine for Large Container Ships
PublicationIn response to global initiatives to reduce greenhouse gas emissions, the maritime industry must adopt green propulsion solutions. This paper analyses the operational potential of very high-temperature reactors (VHTRs) as an innovative propulsion source for large container ships. Calculations are carried out for ships produced between 2018 and 2020 with a capacity of more than 20,000 TEU. For these ships, the average power of the...
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Treatment of Odontogenic Maxillary Sinusitis with the Use of Growth Factors in Advanced Platelet-Rich Fibrin for Immediate Closure of Oro-Antral Communication: A Case Report
PublicationChronic odontogenic maxillary sinusitis (COMS), a prolonged inflammation of the maxillary sinus lasting over 12 weeks, is often a result of periapical lesions, marginal periodontitis, and complications like oro-antral communication (OAC) and fistula (OAF). OAC, commonly emerging post-teeth extraction in the lateral maxilla, lacks documented treatments using advanced platelet-rich fibrin (A-PRF). This study evaluates A-PRF’s efficacy...
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A magnetic imprinted polymer nano-adsorbent with embedded quantum dots and mesoporous carbon for the microextraction of triazine herbicides
PublicationA magnetic molecularly imprinted polymer (MMIP) adsorbent incorporating amino-functionalized magnetite nanoparticles, nitrogen-doped graphene quantum dots and mesoporous carbon (MIP@MPC@NGQDs@ Fe3O4–NH2) was fabricated to extract triazine herbicides from fruit juice. The embedded magnetite nanoparticles simplified the isolation of the adsorbent from the sample solution. The N-GQDs and MPC enhanced adsorption by affinity binding...
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Multitaper-Based Post-processing of Compact Antenna Responses Obtained in Non-anechoic Conditions
PublicationThe process of developing antenna structures typically involves prototype measurements. While accurate validation of far-field performance can be performed in dedicated facilities like anechoic chambers, high cost of construction and maintenance might not justify their use for teaching, or low-budget research scenarios. Non-anechoic experiments provide a cost-effective alternative, however the performance metrics obtained in such...
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A Novel IoT-Perceptive Human Activity Recognition (HAR) Approach Using Multi-Head Convolutional Attention
PublicationTogether with fast advancement of the Internet of Things (IoT), smart healthcare applications and systems are equipped with increasingly more wearable sensors and mobile devices. These sensors are used not only to collect data, but also, and more importantly, to assist in daily activity tracking and analyzing of their users. Various human activity recognition (HAR) approaches are used to enhance such tracking. Most of the existing...
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Playback detection using machine learning with spectrogram features approach
PublicationThis paper presents 2D image processing approach to playback detection in automatic speaker verification (ASV) systems using spectrograms as speech signal representation. Three feature extraction and classification methods: histograms of oriented gradients (HOG) with support vector machines (SVM), HAAR wavelets with AdaBoost classifier and deep convolutional neural networks (CNN) were compared on different data partitions in respect...
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Assessing Acute Toxicity of Selected Packages Internal Layers Extracts using Microtox®
PublicationIn the scientific literature related to the widely understood issue of packaging materials designed to have contact with food (food contact materials), there is much information on raw materials used for their production, as well as their physiochemical properties, types and parameters. Unfortunately, not much attention is given to the issues concerning migration of toxic substances from packaging and its actual influence on the...
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Utilization of rapeseed pellet from fatty acid methyl esters production as an energy source
PublicationRapeseed pellet – crushed seed residue from oil extraction is a by-product of fatty acid methyl esters production process. As other types of biomass, it can either be burned directly in furnaces or processed to increase its energetic value. Biomass is renewable, abundant and has domestic usage; the sources of biomass can help the world reduce its dependence on petroleum products, fossil coal and natural gas. Energetically effective...
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Multivariate analysis of impedance data obtained for coating systems of varying thickness applied on steel
PublicationElectrochemical impedance spectroscopy (EIS) has proven to be a valuable test method for the electrochemical characterization of protective coatings on metals. The common way of analysis in impedance spectroscopy is to model the impedance spectrum by means of an equivalent circuit and to extract the quantity of interest using optimization techniques. A model, corresponding to the behavior of the sample under testing, is important...
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Development of potential candidate reference materials for drugs in bottom sediment, cod and herring tissues
PublicationRegular use of a reference material and participation in a proficiency testing program can improve the reliability of analytical data. This paper presents the preparation of candidate reference materials for the drugs metoprolol, propranolol, carbamazepine, naproxen, and acenocoumarol in freshwater bottom sediment and cod and herring tissues. These reference materials are not available commercially. Drugs (between 7 ng/g and 32...
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Selected issues related to the toxicity of ionic liquids and deep eutectic solvents—a review
PublicationGreen Chemistry plays a more and more important role in implementing rules of sustainable development to prevent environmental pollution caused by technological processes, while simultaneously increasing the production yield. Ionic liquids (ILs) and deep eutectic solvents (DESs) constitute a very broad group of substances. Apart from many imperfections, ILs and DESs have been the most promising discoveries in the world of Green...
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Modeling of a Quasi-Resonant DC Link Inverter Dedicated to Common-Mode Voltage and Ground Current Reduction
PublicationIn this paper, the modeling methodology of the AC drive system with a Parallel Quasi-Resonant DC Link Inverter (PQRDCLI) is described. A presented modeling approach is an attractive tool used for the effective evaluation of a common-mode (CM) voltage and grounds current reduction methods. Designed models of inverter, induction machine (IM), and cable are simple, thus the methods for parameter extraction are not complicated. Verification...
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Optical flow method for measuring deformation of soil specimen subjected to torsional shearing
PublicationIn this study optical flow method was used for soil small deformation measurement in laboratory tests. The main objective was to observe how the deformation distributes along the whole height of cylindrical soil specimen subjected to torsional shearing (TS test). The experiments were conducted on dry non-cohesive soil specimens under two values of isotropic pressure. Specimens were loaded with low-amplitude cyclic torque to analyze...
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An integral-differential method for impedance determination of the hydrogen oxidation process in the presence of carbon monoxide in the proton exchange membrane fuel cell
PublicationThe impedance of a proton exchange membrane fuel cell powered by hydrogen contaminated with carbon monoxide, ranging from 150 to 300 ppb, is measured and discussed. The tested range of CO concentration complied with the fuel standard specified in the ISO standards. Studies of influence of CO contamination on operation of PEMFC are crucial for further development and commercialization of fuel cells for automotive applications. Based...
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Seafloor Characterisation Using Underwater Acoustic Devices
PublicationThe problem of seafloor characterisation is important in the context of management as well as investigation and protection of the marine environment. In the first part of the paper, a review of underwater acoustic technology and methodology used in seafloor characterisation is presented. It consists of the techniques based on the use of singlebeam echosounders and seismic sources, along with those developed for the use of sidescan...
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A magnetic stir bar sorbent of metal organic frameworks, carbon foam decorated zinc oxide and cryogel to enrich and extract parabens and bisphenols from food samples
PublicationA porous composite magnetic stir bar adsorbent was fabricated for the extraction and enrichment of parabens and bisphenols from selected beverage samples. The adsorbent comprised a metal organic framework, carbon foam decorated zinc oxide and magnetic nanoparticles embedded in polyvinyl alcohol cryogel. The porous composite stir bar adsorbent could adsorb parabens and bisphenols via hydrogen bonding, π-π and hydrophobic interactions....
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Granulometric characterization of Arctic driftwood sawdust from frame sawing process
PublicationArctic driftwood can be used as an alternative source of wood as construction timber and furniture material, especially in Iceland and Greenland. The use of Arctic driftwood can help in the fight against climate change, by developing land reforestation processes and reducing the volume harvested wood from forests and sustainability of harvesting processes. In this paper the results of an analysis of the effect of long-term residence...
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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublicationSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...
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Experimental Determination of Limit Adhesive Shear Strtess between Solid Wall and Liquid
PublicationTheoretically slip of a fluid with respect to the solid wall should occur even at a very low velocity of motion. However theoretical analysisand some empirical data suggest that there must be a limit value of shear stress, below which the slip does not appear. A simple metyhod of this stress determination was proposed in the paper.