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A MODEL FOR FORECASTING PM10 LEVELS WITH THE USE OF ARTIFICIAL NEURAL NETWORKS
PublicationThis work presents a method of forecasting the level of PM10 with the use of artificial neural networks. Current level of particulate matter and meteorological data was taken into account in the construction of the model (checked the correlation of each variable and the future level of PM10), and unidirectional networks were used to implement it due to their ease of learning. Then, the configuration of the network (built on the...
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Application of vibrational spectroscopy, thermal analyses and X-Ray diffraction in the rapid evaluation of the stability in solid-state of ranitidine, famotidine and cimetidine
PublicationThis paper reports the study on applicability of Fourier transform infrared (FTIR), near-infrared (NIR) and Raman spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) for the estimation of the chemical stability and photostability of histamine H2-receptor antagonist substances. Ranitidine hydrochloride (RAN), famotidine (FAM) and cimetidine (CIM) were tested and differences in sensitivity were measured...
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Entropy of water calculated from harmonic approximation: estimation of the accuracy of method
PublicationSome molecular dynamics simulations were performed for liquid TIP4P and SPC water at a constant density (1.00 g/cm(3)) and within the temperature range of 5-90 degrees C. By using harmonic approximation, both the entropy of water S-H and the specific heat c(v) were calculated, and the results were compared to literature data. It was found that harmonic approximation overestimates absolute entropy of TIP4P water by 5.6 J/mol K (similar...
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Complexation of amino acids derivatives in water by calix[4]arene phosphonic acids
PublicationSeries of the calix[4]arene phosphonic acids with various substituents at the lower rim was synthesized. Complexing properties of these receptors towards methyl esters of six amino acids strongly depended on the calix[4]arene conformation flexibility. The complex formation processes were monitored using 1H NMR spectroscopy (deuterated phosphate buffer at pD 7.3, 22 oC) and association constant values were evaluated. Inherently...
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Jakość popłuczyn z płukania sieci wodociągowej metodą ukierunkowanego przepływu
Publicationprzedmiotem analizy jest jakość popłuczyn z płukania 80 km sieci wodociągowej w biłgoraju metodą ukierunkowanego przepływu w 2008 r. analizie poddano wyniki badań laboratoryjnych około 300 próbek w zakresie suchej pozostałości i zawartości żelaza ogólnego. największe wartości wskaźników odnotowano w trakcie pierwszej wymiany wody wraz z tendencją malejącą w kolejnych cyklach. bilans usuniętych zanieczyszczeń wskazuje, że masa suchej...
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Physical models in the education of architectural history
PublicationIn this article, the authors present the long tradition and common use of physical models in the process of teaching the history of architecture in higher education institutions. The research described in the article is focused on the use of physical models and mock-ups as stimulants during architectural history classes to support lectures and increase the learning capabilities of students. The authors also cover the general use...
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Evolutionary Algorithm for Selecting Dynamic Signatures Partitioning Approach
PublicationIn the verification of identity, the aim is to increase effectiveness and reduce involvement of verified users. A good compromise between these issues is ensured by dynamic signature verification. The dynamic signature is represented by signals describing the position of the stylus in time. They can be used to determine the velocity or acceleration signal. Values of these signals can be analyzed, interpreted, selected, and compared....
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Imaging polarimeter with high-accuracy measuring principles in crystal optics
PublicationAn imaging polarimeter based on the principles of high-accuracy polarimetry well known in crystal optics is proposed. The application of scientific digital cameras for performance light measurements leads to precise data on polarizers quality, i.e., maps of extinction ratio and transmission axis. Processing of numerous images, acquired at various settings in the polarizer-sample-analyser system, allows to determine the two-dimensional...
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Investigation of the road noise source employing an automatic noise monitoring station
PublicationThe paper presents a pilot investigation of noise source models in two selected localizations in the context of future dynamic noise map creation. The experiments were carried out using the automatic noise monitoring station engineered at the Multimedia Systems Departmentof the Gda´nsk University of Technology. The results of the noise measurements employing monitoring stations and its comparison to the reference values are depicted....
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Diagnosis of Damage in a Steel Tank Model by Shaking Table Harmonic Tests
PublicationThe aim of the present paper is to show the results of the shaking table experimental study concerning the diagnosis of damage in a model of cylindrical steel tank with self-supported roof which is filled with liquid. During the tests, the base of the structure was excited under the harmonic loading with variable frequency. The tests were repeated for different stages of damage, which was introduced in the model by easing the bolts...
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Product Graph Invariants with Applications in the Theory of Information
PublicationThere are a large number of graph invariants. In the paper, we consider some of them, e.g. the independence and chromatic numbers. It is well know that we cannot efficiently calculate these numbers for arbitrary graphs. In the paper we present relations between these invariants and concepts from the theory of information. Concepts such as source coding and transmission over a noisy channel with zero probability of error are modeled...
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Grade of service determination methodology in IP networks with SIP protocol
PublicationAlthough Grade of Service is very important in VoIP providers evaluation, We wasn't able to find any paper regarding the topic of measuring GoS variables for IP networks utilizing SIP, which are defined like for PSTN/ISDN/GSM networks (post-selection delay, answering delay, release delay, or probability of end-to-end blocking). Due to the lack of research in this field, it was necessary to start from defining measures and cover...
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Computer animation system based on rough sets and fuzzy logic
PublicationA fuzzy logic inference system was created, based on the analysis of animated motion features. The objective of the system is to facilitate the creation of high quality animation by analyzing personalized styles contained in numerous animations. Sequences portraying a virtual character acting with a differentiating personalized style (natural or exaggerated) and various levels of fluidity were prepared and subjectively evaluated....
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Pesticide residues levels in honey from apiaries located of Northern Poland
PublicationConcentration levels of 30 pesticide residues were measured in honey samples collected from apiaries in northern part of Poland (Pomerania) using method based on the QuEChERS extraction followed by liquid chromatography-tandem mass spectrometry with electron spray ionization (LC-ESI-MS/MS). In 29% of the samples were found positive for at least some of the target compounds. Concentration of bifenthrin, fenpyroximate, methidathion,...
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Influence of Antimony Substitution on Spontaneous Strain and Thermodynamic Stability of Lanthanum Orthoniobate
PublicationThe analysis of the antimony substitution influence on temperature dependence of unit cell distortion has been done. The values of spontaneous strain and Landau order parameter for three different antimony contents varied had been calculated. The phase transition occurring for antimony substituted lanthanum orthoniobate was found to be second order. The high temperature solution calorimetry method has been used to investigate...
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Formation enthalpies of LaLn׳O3 (Ln׳=Ho, Er, Tm and Yb) interlanthanide perovskites
PublicationHigh-temperature oxide melt solution calorimetry using 3Na2O·MoO3 at 802 °C was performed for interlanthanide perovskites LaLn׳O3 (Ln׳=Ho, Er, Tm and Yb) and lanthanide oxides (La2O3, Ho2O3, Er2O3, Tm2O3 and Yb2O3). The enthalpies of formation of these interlanthanide perovskites from binary lanthanide oxides at room temperature (25 °C) were determined to be −8.3±3.4 kJ/mol for LaHoO3, −9.9±3.0 kJ/mol for LaErO3, −10.8±2.7 kJ/mol...
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An Overview of Image Analysis Techniques in Endoscopic Bleeding Detection
PublicationAuthors review the existing bleeding detection methods focusing their attention on the image processing techniques utilised in the algorithms. In the article, 18 methods were analysed and their functional components were identified. The authors proposed six different groups, to which algorithms’ components were assigned: colour techniques, reflecting features of pixels as individual values, texture techniques, considering spatial...
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Magnetizability of the relativistic hydrogenlike atom in an arbitrary discrete energy eigenstate: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationThe Sturmian expansion of the generalized Dirac--Coulomb Green function [R.\/~Szmytkowski, J.\ Phys.\ B 30 (1997) 825; erratum 30 (1997) 2747] is exploited to derive a closed-form expression for the magnetizability of an arbitrary discrete state of the relativistic one-electron atom with a point-like, spinless and motionless nucleus of charge $Ze$. The result has the form of a double finite sum involving the generalized hypergeometric...
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Apparent Molar Volumes and Expansivities of Ionic Liquids Based on N-Alkyl-N-methylmorpholinium Cations in Acetonitrile
PublicationDensities of some acetonitrile solutions of ionic liquids based on N-alkyl-N-methyl-morpholinium cations, N-ethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, N-butyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, N-methyl-N-octylmorpholinium bis(trifluoromethanesulfonyl)imide and N-decyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide were measured at T = (298.15− 318.15) K and at atmospheric pressure....
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Analysis of balancing of four stroke V6 engines
PublicationAnalysis of balance of V6 engines with a common-pin crankshaft depending on a cylinder bank angle and the crank radius to connecting rod length ratios , based on the relations derived, is presented in the paper. The bank angles providing the lowest moment of inertia forces in reciprocating motion, for selected values, were determined. The position of the plane of the main counterweights in order to maximum balance of the moment...
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Stereo image visualization for a VISROBOT system
PublicationThe article describes a novel approach to robotic vision in mobile robot systems. The system implements a Visrobot system which implements a generic idea of using mobile robots for exploring an indoor environment. The task of such a robot is to visualize a stereo image properly for an operator. The system uses different stereo baseline values. Variable baseline can result in increasing depth resolution for distant objects. We assume...
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Mathematical modelling of implant in an operated hernia for estimation of the repair persistence
PublicationThis paper presents mathematical modelling of an implanted surgical mesh used in the repair process of the abdominal hernia. The synthetic implant is simulated by a membrane structure. The author provides a material modelling of the implant based on the dense net model appropriate for technical fabrics. The accuracy of the proposed solution is evaluated by comparing the simulations of the dynamic behaviour of the system with the...
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Applicability of an effective conductivity approach in modeling thoracic impedance changes
PublicationThis paper describes numerical simulations of the influence of conductivity changes inside a volume conductor on impedance changes measured on its surface. A simple model based on the finite element method has been developed to estimate an applicability of the effective conductivity theory in human chest modeling. The model consisted of a cylinder with two concentric spheres inside. Simulations were performed for two cases: first...
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The Impact of Organizational Culture on Bicycle Commuting Frequency: The Research Based on Example of Three IT companies
PublicationThis chapter describes a study on work-related factors affecting employees’ decision on bicycle commuting. Employees’ transport choices are related to organizational culture. This chapter refers to E. Schein’s definition of organizational culture model. The study was made in order to determine the impact of specific levels of organizational culture on the transport behavior of employees. It is based on a survey performed in three...
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The Magnetic Fluid Seals Research Results vs. Kelvin-Helmholtz (K-H) instability and Preliminary Conclusions
PublicationIn the article a magnetic-fluid seals durability research and the tests results are presented. The tests were made with three magnetic fluids using various magnets quantity in magnetic assemblies. If values obtained in the repeated test deviated by more than 10 % from results of the first test an additional control test was made for final characteristics. The characteristics are: critical pressure, critical motion velocity and...
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The determinants of morphology and properties of the nanohydroxyapatite coating deposited on the Ti13Zr13Nb alloy by electrophoretic techniqe
PublicationThe titanium and its alloys belong at present to the most preferred and commonly applied biomaterials for load- bearing implants. The surfaces of biomaterials are subjected to modification, including the hydroxyapatite coatings deposited in order to ensure corrosion resistance and better joining between an implant and a bone through the possibility of ingrowth bone into the coating. In this paper, the morphology and properties...
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Lightweight glass and metal roof structures in the 19th century. Architecture and construction.
PublicationThe 19th century brought new construction possibilities. The usage of metal elements in mesh structures, filled in with glass, resulted in creating entirely new types of objects. They have distinguished themselves in architecture and technical solutions. The envelope structures giving spatial interiors were arising very quickly. They have been enabling large light penetration, triggering them extremely bright. Thus these building...
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Identification of continuous systems - Practical issues of insensitivity to perturbations
PublicationIn this paper the issue of continuous systems estimation, insensitive to certain perturbations, is discussed. Such an approach has rational advantages, especially when robust schemes are used to assist a target system responsible for industrial diagnostics. This requires that estimated model parameters are generated on-line, and their values are reliable and to a great extent accurate. Practical hints are suggested to challenge...
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Identification of Continuous Systems - Practical Issues of Insensitivity to Perturbations
PublicationIn this paper the issue of continuous systems estimation, insensitive to certain perturbations, is discussed. Such an approach has rational advantages, especially when robust schemes are used to assist a target system responsible for industrial diagnostics. This requires that estimated model parameters are generated on-line, and their values are reliable and to a great extent accurate. Practical hints are suggested to challenge...
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From Linear Classifier to Convolutional Neural Network for Hand Pose Recognition
PublicationRecently gathered image datasets and the new capabilities of high-performance computing systems have allowed developing new artificial neural network models and training algorithms. Using the new machine learning models, computer vision tasks can be accomplished based on the raw values of image pixels instead of specific features. The principle of operation of deep neural networks resembles more and more what we believe to be happening...
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TERMODYNAMIC CALCULATIONS OF TURBINE STEAM PARAMETERS
PublicationIn this work a heat balance was made for the nominal conditions of a block working with 18K370 turbine. For the parameters obtained, the thermal-flow calculations of the steam turbine were performed, maintaining the actual geometry of its flow system. Based on the nominal values obtained, iterative thermal and flow calculations were made for both the heat cycle of the power plant block and the steam turbine itself, seeking to obtain...
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Timber Frame Houses with Different Insulation Materials - Seismic Analysis
PublicationThe aim of this article is to present results of a dynamic numerical analysis focused on the response of two timber frame building structures exposed to seismic excitations. The first structure was insulated with mineral wool, while the second one with polyurethane foam. Specifications and technology involved in the models' construction are based on the previously conducted experimental study, upon which numerical structural models...
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Determination of terpene profiles in potential superfruits
PublicationThe aim of this work was to characterize and compare the profiles of volatile terpenes in four potential superfruits. These profiles were determined using headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography linked to time-of-flight mass spectrometry. The proposed technique allowed the separation and identification of 79 terpenes present in cape gooseberry, crabapple, cherry silver...
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A self-optimization mechanism for generalized adaptive notch smoother
PublicationTracking of nonstationary narrowband signals is often accomplished using algorithms called adaptive notch filters (ANFs). Generalized adaptive notch smoothers (GANSs) extend the concepts of adaptive notch filtering in two directions. Firstly, they are designed to estimate coefficients of nonstationary quasi-periodic systems, rather than signals. Secondly, they employ noncausal processing, which greatly improves their accuracy and...
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Numerical Modeling of Cone Penetration Test in Slightly Overconsolidated Clay with Arbitrary Lagrangian-Eulerian Formulation
PublicationIn this paper the results of the cone penetration test (CPT) modeling with the arbitrary Lagrangian-Eulerian (ALE) formulation provided by Abaqus software package have been presented. The study compares the cone resistance and sleeve friction obtained in numerical analysis with values measured in soundings performed in the uniform layer of clayey soil in the Koszalin area. The clay layer was found to be slightly overconsolidated...
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Evaluation of adhesive forces and the specific surface energy of zirconia stabilized by yttria with alumina additions ceramic by AFM method
PublicationThe adhesive forces and the specific surface energy of ceramic material surfaces are very important for further tribological and biomedical applications of ceramics. Partially stabilized zirconia (zirconium oxide) is popular for manufacturing various medical products. ZrO2 stabilized by Y2O3 with additions of 5 wt% alumina was produced by slip casting method with a subsequent sintering. Structure and chemical composition of ceramic...
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High Temperature Drying Process of Beech Wood (Fagus sylvatica L.) with Different Zones of Sapwood and Red False Heartwood
PublicationThis study examined the changes in the properties of beech wood (Fagus sylvatica L.) after intense drying. Beech wood with false red heartwood was selected as the test specimen. The test samples had dimensions of 50 mm thickness, 180 mm width, and 350 mm length. The specimens were divided into two groups, false red heartwood and sapwood. These specimens were selected with different angles of the growth rings (radial and tangential)....
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A Conformal Circularly Polarized Series-Fed Microstrip Antenna Array Design
PublicationA conformal circularly polarized series-fed microstrip array design for broadside radiation is presented. The array aperture under design is conformal to a cylindrical surface of a given radius. The approach we present primarily addresses focusing of the circularly polarized major lobe of the conformal array by proper dimensioning of the aperture spacings. The proposed analytical models yield the values of the element spacings...
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Remarks on the Subject of Back-Up Protection of Residual Current Devices
PublicationResidual current devices without integral overcurrent protection (RCCBs) are back-up protected by fuses or miniature circuit-breakers (MCBs). If the latter are used, special attention must be given to the coordination between an RCCB and an MCB. This paper indicates probable cases of the aforementioned devices coordination, in which back-up protection of the RCCB is not adequate. A laboratory test has shown that depending on the...
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RSS-Based DoA Estimation for ESPAR Antennas Using Support Vector Machine
PublicationIn this letter, it is shown how direction-of-arrival (DoA) estimation for electronically steerable parasitic array radiator (ESPAR) antennas, which are designed to be integrated within wireless sensor network nodes, can be improved by applying support vector classification approach to received signal strength (RSS) values recorded at an antenna's output port. The proposed method relies on ESPAR antenna's radiation patterns measured...
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A novel heterogeneous model of concrete for numerical modelling of ground penetrating radar
PublicationThe ground penetrating radar (GPR) method has increasingly been applied in the non-destructive testing of reinforced concrete structures. The most common approach to the modelling of radar waves is to consider concrete as a homogeneous material. This paper proposes a novel, heterogeneous, numerical model of concrete for exhaustive interpretation of GPR data. An algorithm for determining the substitute values of the material constants...
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Biotrickling filtration of n-butanol vapors: process monitoring using electronic nose and artificial neural network
PublicationBiotrickling filtration is one of the techniques used to reduce odorants in the air. It is based on the aerobic degradation of pollutants by microorganisms located in the filter bed. The research presents the possibility of using the electronic nose prototype combined with artificial neural network for biofiltration process monitoring in terms of reduction in n-butanol concentration and odour intensity of treated air. The study...
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2-Coloring number revisited
Publication2-Coloring number is a parameter, which is often used in the literature to bound the game chromatic number and other related parameters. However, this parameter has not been precisely studied before. In this paper we aim to fill this gap. In particular we show that the approximation of the game chromatic number by the 2-coloring number can be very poor for many graphs. Additionally we prove that the 2-coloring number may grow...
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Dynamic Bankruptcy Prediction Models for European Enterprises
PublicationThis manuscript is devoted to the issue of forecasting corporate bankruptcy. Determining a firm’s bankruptcy risk is one of the most interesting topics for investors and decision-makers. The aim of the paper is to develop and to evaluate dynamic bankruptcy prediction models for European enterprises. To conduct this objective, four forecasting models are developed with the use of four different methods—fuzzy sets, recurrent and...
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The interaction parameters for solutions of n-butylurea in aqueous solutions of N-methylacetamide – The volumetric and compressibility studies between 288.15 K and 308.15 K
PublicationDensities and speed of sound were measured for solutions of n-butylurea in aqueous solution of Nmethylacetamide 2, 4, 6 and 8 (mol/kg) at T = (288.15, 298.15 and 308.15) K. From these data the apparent molar volumes, Vf, the apparent molar isentropic compressions, KSf, of the solute were determined. The concentration dependencies of the calculated quantities have been used to obtain the standard partial molar parameters. The latter...
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Capacitance Enhancement by Incorporation of Functionalised Carbon Nanotubes into Poly(3,4-Ethylenedioxythiophene)/Graphene Oxide Composites
PublicationThis paper reports on the role of oxidised carbon nanotubes (oxMWCNTs) present in poly-3,4-ethylenedioxytiophene (PEDOT)/graphene oxide (GOx) composite. The final ternary composites (pEDOT/GOx/oxMWCNTs) are synthesised by an electrodeposition process from the suspension-containing monomer, oxidised carbon nanotubes and graphene oxide. Dissociated functional groups on the surface of graphene oxide play a role of counter-ions for the...
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Polarimetric studies of L-arginine-doped potassium dihydrogen phosphate single crystals
PublicationConoscopic interference patterns, channelled spectra and polarimetric techniques have been used for the characterization of pure and doped (with L-arginine amino acid) potassium dihydrogen phosphate (KDP) single crystals. Experimental polarimetric data have been obtained for the frequently used wavelength of 633 nm and for two close wavelengths of 532 and 543 nm in a high-accuracy dual-wavelength polarimeter. The measurement of...
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Resistant to correlated noise and outliers discrete identification of continuous non-linear non-stationary dynamic objects
PublicationIn this article, specific methods of parameter estimation were used to identify the coefficients of continuous models represented by linear and nonlinear differential equations. The necessary discrete-time approximation of the base model is achieved by appropriately tuned FIR linear integral filters. The resulting discrete descriptions, which retain the original continuous parameterization, can then be identified using the classical...
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Resistant to correlated noise and outliers discrete identification of continuous non-linear non-stationary dynamic objects
PublicationIn this study, dedicated methods of parameter estimation were used to identify the coefficients of continuous models represented by linear and nonlinear differential equations. The necessary discrete-time approximation of the base model is achieved by appropriately tuned FIR linear integral filters. The resulting discrete descriptions, which retain the original continuous parameterization, can then be identified using the classical...
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Evaluation of the influence of the opening pressure of a marine Diesel engine injector on the results of numerical simulation of the working cycle and their comparison with the results of the laboratory experiment
PublicationThe article presents the results of a numerical simulation of the working process carried out in a diesel engine. In the applied utility program DIESEL-RK, the laboratory engine Farymann Diesel type D10 was implemented. A selected inoperability of its functional fuel supply system - reduced opening pressure of the injector pinj - was introduced. The values of adequate diagnostic parameters were determined: working gas temperature...