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Neural modelling of dynamic systems with time delays based on an adjusted NEAT algorithm
PublikacjaA problem related to the development of an algorithm designed to find an architecture of artificial neural network used for black-box modelling of dynamic systems with time delays has been addressed in this paper. The proposed algorithm is based on a well-known NeuroEvolution of Augmenting Topologies (NEAT) algorithm. The NEAT algorithm has been adjusted by allowing additional connections within an artificial neural network and...
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Autonomous Ship Utility Model Parameter Estimation Utilising Extended Kalman Filter
PublikacjaIn this paper, a problem of autonomous ship utility model identification for control purposes is considered. In particular, the problem is formulated in terms of model parameter estimation (one-step-ahead prediction). This is a complex task due to lack of measurements of the parameter values, their time-variability and structural uncertainty introduced by the available models. In this work, authors consider and compare two utility...
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A Power-Efficient Digital Technique for Gain and Offset Correction in Slope ADCs
PublikacjaIn this brief, a power-efficient digital technique for gain and offset correction in slope analog-to-digital converters (ADCs) has been proposed. The technique is especially useful for imaging arrays with massively parallel image acquisition where simultaneous compensation of dark signal non-uniformity (DSNU) as well as photo-response non-uniformity (PRNU) is critical. The presented approach is based on stopping the ADC clock by...
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Modelling of residential sales price with kriging using different distance metrics in different correlation functions
PublikacjaThe modelling and estimation of sales prices based on economical conditions are important for housing sector especially in developing countries. Analysts are focused on the subject to analyze price movements and estimate the future trend of the sales prices for housing sector. In this study, we tried to generate a robust and efficient model related to the subject. Firstly, we investigated economic variables affecting housing sales...
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Overview of the three multicriteria approaches applied to a global assessment of analytical methods
PublikacjaCritical and global evaluation of analytical methods should be one of the primary goals in analytical chemistry. A holistic approach, however, requires a look at the varied features: commonly discussed validation criteria, often underrated practical and economic aspects, and typically overlooked compliance with the principles of green analytical chemistry. Carrying out such an assessment in a critical and transparent way is extremely...
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Highly-Compact Dual-Band Bandpass Waveguide Filter Based on Cross-Shaped Frequency-Dependent Coupling
PublikacjaThis work reports the design of an original class of highly-compact dual-band bandpass filter based on dual-mode waveguide resonators inter-coupled through a novel type of frequency-dependent coupling (FDC). The devised FDC consists of a cross-shaped metallic structure placed in the broad wall of a rectangular waveguide. This FDC produces two additional poles and three extra transmission zeros (TZs). Specifically, each pole is...
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Simple smartphone-based methods for the determination of bioactive compounds in wine
PublikacjaA set of simple smartphone-based methods of bioactive compounds determination were developed for wine analysis. Procedures for smartphone-based determination of the total content of phenolic compounds, flavonoids, anthocyanins and biogenic amines, as well as measurement of antioxidant activity were developed and fully validated. The experimental setup is based on smartphone and 3D-printed device, though it is very simple and can...
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The Application of Fluidic Sealing in Shrouded Gas Turbine Blades
PublikacjaThis paper presents a study conducted on a new gas turbine designed to limit leakage in the labyrinth seal. The slots in the fin are used to generate a bypass flow, which obstructs the flow in the gap above the fin. The method was tested numerically and experimentally beforehand using a simplified model without rotation or blade passages. In this paper, the validation of the method using a model of a turbine stage is shown. Reynolds-averaged...
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Angle Tracking Observer for Filtering Rotor Position Estimates in Sensorless Electric Drives
PublikacjaSensorless electric drives use measurements of electrical quantities to estimate rotor position and speed. Measurement errors deteriorate the estimation accuracy, thus additional means are necessary to remove high-frequency components from estimated signals. This paper proposes to use an Angle Tracking Observer (ATO) for reducing noise in rotor position estimates, which is related to random errors in the measurements. A simplified,...
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Rapid multi-objective design optimisation of compact microwave couplers by means of physics-based surrogates
PublikacjaThe authors introduce a methodology for fast multi-objective design optimisation of miniaturised microwave couplers. The approach exploits the surrogate-based optimisation paradigm with an underlying low-fidelity model constructed from an equivalent circuit of the structure under consideration, corrected through implicit and frequency space mapping. A fast prediction tool obtained this way is subsequently optimised by a multi-objective...
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Elektrochemiczny czujnik na bazie cieczy jonowej do oznaczania par benzaldehydu
PublikacjaW pracy przedstawiono prototypowy, laboratoryjny, elektrochemiczny czujnik do oznaczania par benzaldehydu w argonie. Cieczą jonową testowaną jako elektrolit i środowisko reakcji redox była: bis(trifluorometylosulfonylo)imidek 1-butylo,3-metyloimidazolinowy ([BMIM][Tf2N]). W pomiarach użyto komercyjnych elektrod firm: DropSens Co. i BVT Technologies. Walidacji poddano dwa parametry metrologiczne czujnika: granicę wykrywalności i...
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Expedited Design Closure of Antennas By Means Of Trust-Region-Based Adaptive Response Scaling
PublikacjaIn the letter, a reliable procedure for expedited design optimization of antenna structures by means of trust-region adaptive response scaling (TR-ARS) is proposed. The presented approach exploits two-level electromagnetic (EM) simulation models. A predicted high-fidelity model response is obtained by applying nonlinear frequency and amplitude correction to the low-fidelity model. The surrogate created this way is iteratively rebuilt...
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Ergonomic Aspects of Development of Architecture in the Context of Sanitary and Hygiene Safety
PublikacjaAbstract Ergonomics answers the need of safe development of space by creating spatial forms which help to implement the safety procedures and limit the threats involved both in ordinary use of the spaces and in case of unforeseen events. Using the knowledge of ergonomics and architecture on the basis of defining the routes of germ transmission, allows to limit the spread of those organisms. Ergonomics of developing architectural...
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Experimental investigation on straight and u-bend double tube heat exchanger with active and passive enhancement methods
PublikacjaAuthors in this work want to demonstrate the possibility to increase the heat transfer efficiency by using simple wire coil inserts to create turbulent flow in the boundary layer as well as air blowing into the annulus of the pipe. In the study, Wilson plot approach was applied in order to estimate heat transfer coefficients for all heat exchanger (HX) configurations. The study focuses on experimental values of heat transfer coefficient...
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Fast surrogate-assisted simulation-driven design of compact microwave hybrid couplers
PublikacjaThis work presents a robust methodology for expedited simulation-driven design optimization of compact microwave hybrid couplers. The technique relies on problem decomposition, and a bot-tom–up design strategy, starting from the level of basic building blocks of the coupler, and finishing with a tuning procedure that exploits a fast surrogate model of the entire structure. The latter is constructed by cascading local response surface...
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Crowdsourcing-Based Evaluation of Automatic References Between WordNet and Wikipedia
PublikacjaThe paper presents an approach to build references (also called mappings) between WordNet and Wikipedia. We propose four algorithms used for automatic construction of the references. Then, based on an aggregation algorithm, we produce an initial set of mappings that has been evaluated in a cooperative way. For that purpose, we implement a system for the distribution of evaluation tasks, that have been solved by the user community....
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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
PublikacjaThis 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,...
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Objective relaxation algorithm for reliable simulation-driven size reduction of antenna structure
PublikacjaThis letter investigates reliable size reduction of antennas through electromagnetic-driven optimization. It is demonstrated that conventional formulation of the design task by direct footprint miniaturization with imposing constraints on electrical performance parameters may not lead to optimum results. The reason is that—in a typical antenna structure—only a few geometry parameters explicitly determine the antenna footprint,...
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Single-phase, Five-level Inverter with SPWM-Based Neutral Point Voltage Balancing Scheme
PublikacjaMultilevel inverter topologies provide several advantages over two-level inverter configuration. These benefits are the reason for the growing interest in multilevel topologies among research society. One of the most popular topological concepts (diode and active switch clamping) requires neutral-point potential balancing due to series-connected capacitor banks across the input dc link in such derived inverter configurations. This...
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Electron-scattering cross sections for selected alkyne molecules: Measurements and calculations
PublikacjaWe report cross-section results from experimental and theoretical studies on electron collisions with 1-butyne (HC≡C–CH2CH3) and acetylene (HC≡CH) molecules and from computations for a propyne (HC≡C–CH3) molecule. Absolute grand -total electron-scattering cross sections (TCSs) were measured at impact energies ranging from about 0.5 to 300 eV using the linear electron-transmission method. The TCS energy curve for 1-butyne has a...
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Numerical estimation of the pile toe and shaft unit resistances during the installation process in sands
PublikacjaNumerical simulations of a pile jacking were carried out. A Coupled Eulerian–Lagrangian (CEL) formulation was used to treat with large deformation problems. An Abaqus, a commercial Finite Element Method software suit, was used as a computing environment. The Mohr–Coulomb constitutive model was applied and the Coulomb model of friction was used to describe pile-soil interaction. Calculations were made for three different pile diameters....
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The elasto-plastic numerical study of crack initiation in notched PMMA specimens under uniaxial loading conditions – Tension and torsion
PublikacjaThis paper presents the results of FEM numerical calculations aimed at describing the plastic strain and stress fields under critical loading conditions: tensile force or torsional moment. The calculations were carried out with reference to the results of experimental tensile and torsional tests of flat PMMA specimens weakened with V-notches of different root radii: 0.5, 2 and 10 mm. The procedure for conducting nonlinear numerical...
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Validation and Regulatory Issues for Sample Preparation
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Numerical and experimental propeller noise investigations
PublikacjaThe standard propeller has been investigated in model scale, using medium size cavitation tunnel. The hydroacoustic characteristics of propellers under different loading conditions have been investigated. Additionally the presented experimental results have been used for the verification of applied numerical approach. During both numerical and experimental analyses non-uniform inflow propeller’s conditions have been adapted. Good...
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Numerical studies on the influence of selected construction features and road conditions on the performance of road cable barriers
PublikacjaCable barriers are commonly used on Polish roads, including motorways and local roads. Their main elements are pre-stressed wire ropes, which are usually anchored at two ends in concrete blocks buried in the soil. In this work numerical studies concerning the influence of selected construction features and parameters of the vehicle motion on the performance of cable barriers were performed. Numerical simulations are a useful tool...
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Numerical simulation of hardening of concrete plate
PublikacjaThe paper presents a theoretical formulation of concrete curing in order to predict temperature evolution and strength development. The model of heat flow is based on a well-known Fourier equation. The numerical solution is implemented by means of the Finite Difference Method. In order to verify the model, the in situ temperature measurements at the top plate of a road bridge were carried out. A high agreement between numerical...
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Ab initio and density functional theory calculations of proton affinities for volatile organic compounds
PublikacjaThe Hatree-Fock method with 6-311G** split-valence molecular orbitals basis sets and the density function theory-B3LYP have been applied to geometrical optimizations and calculations of total electronic, zero point vibrational energies and proton affinities at 298 K for volatile organic compounds. Calculated values of proton affinities are compared with experimental data.
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Numerical crash analysis of the cable barrier
PublikacjaSafety barriers are used to increase road safety. Their basic task is to prevent the errant vehicle from getting off the road in places which are potentially dangerous for vehicle passengers. Barriers, which are used on European roads, must fulfill the requirements of EN 1317 standards by passing appropriate crash tests. Because of their high cost, numerical simulations are increasingly used to evaluate the properties of safety...
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Computed vibrational excitation ofCF4by low-energy electrons and positrons: Comparing calculations and experiments
PublikacjaQuantum calculations for the excitation of the asymmetric modes of the CF4 target gas, ν3 and ν4, by impact of low-energy electrons and positrons are carried out in the energy range around 1 eV and are compared with recent experimental findings. The similarities and differences between the two types of projectiles, and the two different modes, are analyzed and discussed vis à vis the present accord with the experimental results.
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Investigations of size effect in concrete at aggregate level - experiments and calculations results using discrete element method
PublikacjaSize effect is a fundamental phenomenon in concrete. It is characterised by decreasing strength and increasing brittleness of concrete with increasing size. The thesis includes experimental and theoretical elements. The main goal of the thesis were investigations of a size effect at the aggregate level by taking fracture into account with the discrete element method (DEM) for various failure modes. Comprehensive experiments on...
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Numerical Simulations for Transonic Flow in Control Valve
PublikacjaResults of numerical simulations for transonic flow in control valve are presented. The valve is the main part of an adaptive pneumatic shock absorber. Flow structure in the valve domain and the influence of the flow non-uniformity in the valve on a mass flow rate is investigated. Numerical simulation results are compared with experimental data.
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Cost‐efficient performance‐driven modelling of multi‐band antennas by variable‐fidelity electromagnetic simulations and customized space mapping
PublikacjaElectromagnetic (EM) simulations have become an indispensable tool in the design of contemporary antennas. EM‐driven tasks, for example, parametric optimization, entail considerable computational efforts, which may be reduced by employing surrogate models. Yet, data‐driven modelling of antenna characteristics is largely hindered by the curse of dimensionality. This may be addressed using the recently reported domain‐confinement...
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NUMERICAL ANALYSIS OF SPECIES DIFFUSION AND METHANOL DECOMPOSITION IN THERMOCATALYTIC REACTOR BASED ON THE INTERMETALLIC PHASE OF Ni3Al FOR LOW REYNOLDS NUMBERS
PublikacjaNumerical modelling of hydrogen production by means of methanol decomposition in a thermocatalytic reactor using corrugated foil made of the Ni3Al intermetallic phase is shown in the paper. Experimental results of the flow analysis of mixtures containing helium and methanol in a thermocatalytic reactor with microchannels were used for the initial calibration of the CFD calculations (calculations based on the Computational Fluid...
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Numerical analysis of crack propagation in silicone nitride
PublikacjaThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. The influence of ring crack size on rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculation...
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Numerical analysis of a temporary steel grandstand
PublikacjaThe purpose of this paper is to present the results of the numerical analysis focused on the response of the temporary steel scaffolding grandstand subjected to human-induced vibrations due to jumping. Shell as well as beam elements have been used in the numerical model. Its first stage has involved conducting modal analysis in order to determine the modes of free vibrations and the corresponding natural frequencies for the empty...
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Numerical Modelling of Shear Localization in Granular Bodies using MPM and Non-local Hypoplasticity
PublikacjaThe paper deals with modelling of shear localization in granular bodies by means of an enhanced hypoplastic constitutive model and material point method (MPM). The calculations were carried out for plane strain compression of non-cohesive sand. In order to properly capture the width and inclination of shear zones, the constitutive model was enriched by a characteristic length of micro-structure by means of a non-local theory....
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Electroelastic biaxial compression of nanoplates considering piezoelectric effects
PublikacjaIn the present theoretical work, it is assumed that a piezoelectric nanoplate is connected to the voltage meter which voltages have resulted from deformation of the plate due to in-plane compressive forces whether they are critical buckling loads or arbitrary forces. In order to derive governing equations, a simplified four-variable shear deformation plate theory has been employed using Hamilton’s principle and Von-Kármán...
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Evaluation of excessive noise effects on hearing employing psychoacoustic dosimetry
PublikacjaResearch results regarding the noise impact on hearing applying the concept of the Psychoacoustic Noise Dosimetry (PND) are presented. The general characteristics of the PND algorithm are discussed. Additionally, the results of hearing examinations conducted in the laboratory conditions are shown. The main objective of the research was to determine the time needed for the Temporary Threshold Shift to reverse. The results were used...
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Influence of Properties of Hydraulic Fluid on Pressure Peaks in Axial Piston Pumps’ Chambers
PublikacjaThe article concentrates on the research of the pressure peaks in a working chamber of an axial piston pump. The main focus of the article is the influence of fluid properties on the pressure peaks value. Experimental and analytical methods were used to determine the impact of the fluid density, viscosity, compressibility and aeration. The article describes the pressure peak generation process and explains the theoretical basis...
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Assurance Case Patterns On-line Catalogue
PublikacjaAssurance case is an evidence-based argument demonstrating that a given property of a system (e.g. safety, security) is assured. Assurance cases are developed for high integrity systems, as in many industry domains such argu-ment is explicitly required by regulations. Despite the fact that each assurance case is unique, several reusable argument patterns have been identified and pub-lished. This paper reports work on development...
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INFLUENCE OF BISMUTH CONTENT ON COMPLEX IMMITTANCE CHARACTERISTICS OF PRESSURELESS SINTERED BiNbO4 CERAMICS
PublikacjaGoal of the present research was to study immittance properties of BiNbO4 ceramics fabricated by the solid state reaction route followed by pressureless sintering. Four sets of samples were examined, namely the one fabricated from the stoichiometric mixture of oxides, viz. Bi2O3 and Nb2O5 as well as the ones with an excess of 3%, 5% and 10% by mole of Bi2O3. The immittance properties were studied by impedance spectroscopy. Measurements...
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Multibody models for gait analysis
PublikacjaThe aim of this study was to create multibody biomechanical models to analyze a normal gait of the human. Proposed models can be used to identify joint moments of the lower limbs during normal gait in the single and double support phases. Applying Newton-Euler formulation, following planar models were developed: 1) a mathematical 6DOF model describing a gait in the sagittal plane of the body for single support phase and double...
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Measurements of Path Loss in Off-Body Channels in Indoor Environments
PublikacjaThis paper presents a measurements of the path loss for validation of a statistical model for off-body radio channels in an indoor multipath environment, which considers the distance dependent mean path loss, and describes body shadowing and fast fading components in a statistical way. The measurement equipment and propagation indoor environment have been presented. Two different bodies and five static and two walking scenarios...
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Comparison of High Performance Liquid Chromatography Methods with Different Detectors for Determination of Steroid Hormones in Aqueous Matrices
PublikacjaThis paper presents the development and comparison of procedures for the qualitative and quantitative determination of five estrogenic compounds (17-a-ethynylestradiol, estrone, estradiol, estriol, and progesterone) in drinking water and wastewater samples. Five extraction columns and two disks were tested for their efficiency. The C18 columns were superior on the basis of cost for solid phase extraction of drinking water or sewage....
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Rapid multi-objective antenna design using point-by-point Pareto set identification and local surrogate models
PublikacjaAntenna design is inherently a multicriterial problem.Determination of the best possible tradeoffs between conflicting objectives (a so-called Pareto front), such as reflection response, gain, and antenna size, is indispensable from the designer’s point of view, yet challenging when high-fidelity electromagnetic (EM) simulations are utilized for performance evaluation. Here, a novel and computationally...
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Natura i dziedzictwo – Cele Zrównoważonego Rozwoju (SDG) jako czynniki integracji społecznej w przestrzeniach osiedli mieszkaniowych. Studium Zaspy./ Nature and heritage – Sustainable Development Goals (SDG) as factors of social integration in the space of housing estates. Study of Zaspa
PublikacjaThis article introduces the topic of revitalising outdoor common spaces in existing housing developments. The aim of the research is to present universal design models by analysing nature and heritage as dominant values, complementing perceived natural and cultural deficiencies. For this purpose, the Sustainable Development Goals (SDG), UNESCO (UNESCO, 2015) and the Research Through Design (RTD) method were used. The Zaspa housing...
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Topography measurement methods evaluation for entire bending-fatigued fracture surfaces of specimens obtained by explosive welding
PublikacjaIn this paper, the methods of compensation of differences in the results of entire bending-fatigued fracture surface topographies were presented. The roughness evaluation was performed with a focus variation microscope and confocal surface topography measurement techniques. The differences in the ISO 25178 roughness parameters were investigated and procedures for their compensation were studied. It was found that various types...
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APPLICATION OF ULTRAFAST GAS CHROMATOGRAPHY TO RECOGNIZE ODOR NUISANCE
PublikacjaPotentialities of ultrafast gas chromatography applied to periodical monitoring of odor nuisance originating from a municipal landfill have been examined. The results of investigation on classification of the atmospheric air samples collected in a vicinity of the landfill during winter and summer season have been presented. The investigation was performed using ultrafast gas chromatography of Fast/Flash GC type HERACLES II by Alpha...
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Comparison of the Measurement Techniques Employed for Evaluation of Ambient Air Odour Quality Influenced by Operation of Industrial Sewage Treatment Plant
PublikacjaThe paper presents the results of investigation on ambient air quality evaluation with respect to concentration of odorants in a vicinity of a sewage treatment plant of the LOTOS Group S.A. petroleum plant. The investigation was performed during winter season using a prototype of electronic nose and the Nasal Ranger field olfactometers. The prototype was equipped with a set of six semiconductor sensors by FIGARO Co. and one PID-type...
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Monitoring of odour nuisance in the Tricity Agglomeration
PublikacjaThe paper describes a principle of operation of odour nuisance monitoring network, which is being designed in the Tricity Agglomeration. Moreover, it presents the preliminary results of an investigation on ambient air quality with respect to odour nuisance in a vicinity of the municipal landfill. The investigation was performed during spring-winter season using a prototype of electronic nose and the Nasal Ranger field olfactometers. The...