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Search results for: PROPOSED SNSFD SCHEMESTABILITY ANALYSIS OF SCHEMECONSISTENCY OF SCHEMEEXACT SOLUTIONSSTOCHASTIC GROSS–PITAEVSKII EQUATION (SGPE)SSE TECHNIQUEMERF TECHNIQUE
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Post-failure fracture surface analysis of notched steel specimens after bending-torsion fatigue
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An Analysis of Elliptical-Rectangular Patch Structure on Multilayer Elliptic Cylinders
PublicationThe resonance frequency problem of an ellipticalrectangular patch mounted on multilayered dielectric coated elliptic conducting cylinder, is investigated in this paper. A fullwave analysis and a moment-method calculation are employed. The analysis is carried out considering the expansion of the field as a series of Mathieu functions. An additional theorem for Mathieu functions is utilized to investigate the non-confocal ellipse...
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PREDICTING CORPORATE BANKRUPTCIES IN POLAND AND LITHUANIA – COMPARATIVE ANALYSIS
PublicationThe research on predicting bankruptcies of enterprises constitutes one of the most important areas of financial management. In developed countries, the first publications on the subject appeared in the early 20th century. The situation is different in the countries of Eastern Europe, which introduced the market system already at the beginning of the 1990s, which resulted in first corporate bankruptcies. The article...
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Use of numerical methods in the analysis of traction energy systems—an overview of the practical examples
PublicationA characteristic feature of trolleybus transport is the random nature of traffic caused by congestion. It predestinates statistical and numerical methods for the analysis of trolleybus energy system. There are presented 3 methods of trolleybus traction system analysis: simulation of supply system based on Monte Carlo method, analysis of energy recovery potential based on statistical data analysis and benchmark of trolleybus supply...
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COMPUTER ANALYSIS OF HYDRAULIC CONDITIONS IN A SANITARY CHAMBER
PublicationThis paper presents analysis of hydraulic conditions of sewage flow down the slipway (ramp) in the collecting sanitary chamber connecting 3 collectors on the inlet: ⌀600, ⌀800 and ⌀1400 and one on the outlet ⌀1600 mm, with a maximum difference of elevation 5 m. The mathematical model has been made and hydraulic calculations were carried out in steady flow conditions. Then wastewater surface elevation, energy grade line elevation,...
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Comparative analysis of different numerical models of a steel radial gate
PublicationHydrotechnical structures are important components in water management system and general flooding safety. Their reliability should be ensured since potential damage might lead to catastrophic consequences. Weir gates are considered to be highly vulnerable elements of each hydro power plant, with regard to its dynamic resistance. The aim of the paper is to compare different numerical models and their influence on the results of...
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Timber frame houses resistant to dynamic loads - seismic analysis
PublicationThe aim of the article is to present results of seismic analysis results of two real-sized timber frame buildings subjected to seismic excitations. The first model was insulated with mineral wool, the second one with polyurethane foam. Technology and specifications involved in both models construction is based on the previously conducted experimental research on timber frame houses, including wall panels tests, wall numerical models...
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The Application of Satellite Image Analysis in Oil Spill Detection
PublicationIn recent years, there has been an increasing use of satellite sensors to detect and track oil spills. The satellite bands, namely visible, short, medium infrared, and microwave radar bands, are used for this purpose. The use of satellite images is extremely valuable for oil spill analysis. With satellite images, we can identify the source of leakage and assess the extent of potential damage. However, it is not yet clear how to...
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Application of multicriteria decision analysis in solvent type optimization for chlorophenols determination with a dispersive liquid–liquid microextraction
PublicationThis study presents a novel support tool for the optimization and development of analytical methods. The tool is based on multi-criteria decision analysis (MCDA), namely the Technique for Order of Preference by Similarity to the Ideal Solution (TOPSIS), that allows users to rank possible solutions according to their requirements. In this study, we performed rankings of pairs of eight extraction and three dispersive solvents used...
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Sensitivity analysis in design process of sandwich U-shaped composite footbridge
PublicationThe structure of the sandwich composite footbridge of a 14 metre span length and U-shaped cross-section was analysed. Sensitivity analysis was performed to support the design process of this innovative object. Linear discrete sensitivity analysis was performed by means of finite element method. The influence of vari-ation of several design variables i.e. thicknesses of inner and outer laminates on the mid-span deflection, as-sumed...
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The smoothness test for a density function
PublicationThe problem of testing hypothesis that a density function has no more than μ derivatives versus it has more than μ derivatives is considered. For a solution, the L2 norms of wavelet orthogonal projections on some orthogonal ‘‘differences’’ of spaces from a multiresolution analysis is used. For the construction of the smoothness test an asymptotic distribution of a smoothness estimator is used. To analyze that asymptotic distribution,...
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Application of autoencoder to traffic noise analysis
PublicationThe aim of an autoencoder neural network is to transform the input data into a lower-dimensional code and then to reconstruct the output from this code representation. Applications of autoencoders to classifying sound events in the road traffic have not been found in the literature. The presented research aims to determine whether such an unsupervised learning method may be used for deploying classification algorithms applied to...
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Analog modelling in qualitative analysis of vibration propagation
PublicationThe theory of dynamic systems is usually used to model the real systems. The models are based on solving ordinary differential equations, partial or difference, which enable obtaining the relation between input signal and the system response (output signal). The analogy between those models and generalized dynamic systems or control systems can be practically used. Vibration propagation can be described in a similar way as the...
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Human Factors and Cognitive Engineering in Functional Safety Analysis
PublicationHuman factors and cognitive engineering are considered nowadays as important multidisciplinary domains that focus on improving the relations between humans, technology and systems to be supervised and operated. The industrial automation and control systems (IACS) in hazardous plants are increasingly computerized and perform various safety functions. These are usually designed and implemented according to the functional safety requirements....
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Stability Analysis of Shunt Active Power Filter with Predictive Closed-Loop Control of Supply Current
PublicationThis paper presents a shunt active power filter connected to the grid via an LCL coupling circuit with implemented closed‐loop control. The proposed control system allows selective harmonic currents compensation up to the 50th harmonic with the utilization of a model‐based predictive current controller. As the system is fully predictive, it provides high effectiveness of the harmonic reduction, which is proved by waveforms achieved...
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Behavior Analysis and Dynamic Crowd Management in Video Surveillance System
PublicationA concept and practical implementation of a crowd management system which acquires input data by the set of monitoring cameras is presented. Two leading threads are considered. First concerns the crowd behavior analysis. Second thread focuses on detection of a hold-ups in the doorway. The optical flow combined with soft computing methods (neural network) is employed to evaluate the type of crowd behavior, and fuzzy logic aids detection...
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Numerical modal analysis of a vertical rising steel water gate
PublicationVertical rising steel water gates are very common not only in Poland and Germany but also in other countries of the world. Their popularity is mainly attributed to their simplicity of construction, which makes their production process cheaper and faster when compared to other solutions. The aim of this paper is to conduct a numerical modal analysis to examine the eigenvalues and eigenmodes of a vertical rising steel gate. Two cases...
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FEM ANALYSIS AND EXPERIMENTAL TESTS OF RIGID RISER HANGING SYSTEM
PublicationThe article presents the analysis, project, and experimental examination of an original rigid riser for Coil Tubing Pipes. The principle of riser operation is based on the use of friction forces. The research included the FEM analysis of the designed riser, calculations of the required bolt tensions, and checking the effect of the clamping force on stress distribution in the pipeline. The results of computer simulation were verified...
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Analysis and interpretation of radiometric signals in a liquid-gas bubble flow
PublicationThe article presents the analysis of signals from a radiometric system consisting of two scintillation probes and two gamma radiation sealed sources. Calculations and interpretation were carried out for the bubble flow of the water-air mixture in the horizontal pipeline. The analysis of the obtained signals was done in time and frequency domain. In the frequency domain, a range of usable frequencies was identified, which were associated...
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Perturbation analysis of electric field around objects in sea water
PublicationThe paper presents an analytical approach to the perturbation analysis of electric field distribution caused by a sphere and an ellipsoid placed in a uniform electric field.
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Analysis of wave propagation in a bolted steel joint
PublicationThe paper presents results of numerical and experimental investigations of elastic wave propagation in a bolted single-lap joint. The research was carried out for both symmetric and antisymmetric Lamb wave modes. In experimental studies the PZT transducers were used to excite and register wave propagation signals. The controlled value of the torque during measurements was ensured by the use of high precision torque wrenches. Numerical...
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Implementation of Hermite-Ritz method and Navier’s Technique for Vibration of Functionally Graded Porous Nanobeam Embedded in Winkler-Pasternak Elastic Foundation Using bi-Helmholtz type of nonlocal elasticity
PublicationPresent study is devoted to investigating the vibration characteristics of Functionally Graded (FG) porous nanobeam embedded in an elastic substrate of Winkler-Pasternak type. Classical beam theory (CBT) or Euler-Bernoulli beam theory (EBT) has been incorporated to address the displacement of the FG nanobeam. Bi-Helmholtz type of nonlocal elasticity is being used to capture the small scale effect of the FG nanobeam. Further, the...
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Analysis of the Impact of Galileo Observations on the Tropospheric Delays Estimation
PublicationIn this study we present analysis of the impact of Galileo observations on the ZTD and tropospheric gradients estimation. The tropospheric parameters were obtained in various scenarios, which differ from each other only in used satellite systems: Galileo-only, GPS-only, GPS/Galileo, GPS/GLONASS and GPS/GLONASS/Galileo. Then, comparative analysis between Galileo-only solution and the other ones, was carried out. As a reference,...
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Analysis of allophones based on audio signal recordings and parameterization
PublicationThe aim of this study is to develop an allophonic description of English plosive consonants based on recordings of 600 specially selected words. Allophonic variations addressed in the study may have two sources: positional and contextual. The former one depends on the syllabic or prosodic position in which a particular phoneme occurs. Contextual allophony is conditioned by the local phonetic environment. Co-articulation overlapping...
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Structural changes in the polish economy- the analysis of input-output
Publicationthis paper analyses the structure of polish economy using three input-output tables for years 1995, 2000 and 2004. applying the traditional methods proposed by rasmussen the sector's backward and forward linkages are identified. industries with large backward and forward linkages are named "key sectors" and play an important role in the development strategy of a country, so the outcome of the paper may be used for the development...
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Stress analysis of the bridge hangers in terms of the fatigue verification
PublicationThe paper presents the results of numerical stress analysis of the bridge rod hangers. Two types of hangers were taken into account, i.e. the bolted hanger and the welded hanger. A detailed FEM shell models of the connection area between the hanger and the bridge span have been developed. Local stress concentration effects have been investigated in terms of fatigue verification.
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Analysis of radiometric signal in sedimentating suspension flow in open channel
PublicationThe article discusses issues related to the estimation of the sedimentating solid particles average flow velocity in an open channel using radiometric methods. Due to the composition of the compound, which formed water and diatomite, received data have a very weak signal to noise ratio. In the process analysis the known determining of the solid phase transportation time delay the classical cross-correlation function is the most...
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Selected concentration techniques for gas chromatographic analysis of environmental samples
PublicationThe paper describes the role and tasks of environmental analysis and monitoring. It emphasises the leading role played by gas chromatography, especially when coupled with suitable sample preparation. This is demonstrated by some literature evidence and mainly by the author's original work on the design of sample preparation apparatus and development of GC-based methods of determination of a wide variety of organic pollutants in...
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Monolithic polydimethylsiloxane-modified silica composites prepared by a low-temperature sol–gel micromolding technique for controlled drug release
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Impact of sensitization on dissolution process of AISI 304 stainless steel during intergranular corrosion evaluated using DEIS technique
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Impact of sensitization on dissolution process of AISI 304 stainless steel during intergranular corrosion evaluated using DES technique
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Application of passive sampling technique for monitoring of BTEX concentration in urban air: Field comparison of different types of passive samplers
PublicationW efekcie przeprowadzonych badań potwierdzono przydatności techniki dozymetrii pasywnej wykorzystywanej na etapie izolacji i wzbogacania analitów do uzyskania informacji o poziomie stężeń zanieczyszczeń z grupy BTEX w powietrzu atmosferycznym na terenie aglomeracji Trójmiejskiej. Dodatkowo, porównano wyniki oznaczeń uzyskanych z wykorzystaniem dwóch typów dozymetrów pasywnych.
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Verification of the homogeneity of the matrix/analyte mixture on sample plate using MALDI-MS technique and new ionic liquid matrices
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Purification and recovery of laccase produced by submerged cultures of Trametes versicolor by three-phase partitioning as a simple and highly efficient technique
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Estimation of platinum in environmental water samples with solid phase extraction technique using inductively coupled plasma mass spectrometry
PublicationZoptymalizowano metodykę oznaczania śladowych poziomów stężeń platyny (IV) w oparciu o technikę ekstrakcji do fazy stałej w połączeniu ze spektrometrią mas z plazmą wzbudzoną indukcyjnie. Na etapie wzbogacania platyny wykorzystano żel krzemionkowy modyfikowany grupami aminopropylowymi. Ilościowy odzysk platyny uzyskano poprzez wykorzystanie 1.0 mol L-1 roztworu tiomocznika jako eluenta. Odchylenie standardowe wyników (RSD) było...
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Identification of predicted genes expressed differentially in pituitary gland tissue of young growing bulls revealed by cDNA-AFLP technique
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Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a neonatal unit: control of an outbreak using a new ADSRRS technique
PublicationSzczepy Klebsiella pneumoniae (EPKP)produkujące beta-laktamazy o rozszerzonym spektrum substratowym (ESBL)stanowią często problem zakażeń na oddziałach noworodkowych. Izolaty od 149 pacjentów poddano typowaniu nową metodą opartą na zjawisku supresji PCR, ADSRRS-fingerprinting, wykazując pochodzenie klonalne badanych szczepów. Użyteczność techniki ADSRRS-finerprinting została potwierdzona innymi metodami - RAPD i PFGE.
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On the Handling of Outliers in the GNSS Time Series by Means of the Noise and Probability Analysis
PublicationThe data pre-analysis plays a significant role in the noise determination. The most important issue is to find an optimum criterion for outliers removal, since their existence can affect any further analysis. The noises in the GNSS time series are characterized by spectral index and amplitudes that can be determined with a few different methods. In this research, the Maximum Likelihood Estimation (MLE) was used. The noise amplitudes...
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Thermal Images Analysis Methods using Deep Learning Techniques for the Needs of Remote Medical Diagnostics
PublicationRemote medical diagnostic solutions have recently gained more importance due to global demographic shifts and play a key role in evaluation of health status during epidemic. Contactless estimation of vital signs with image processing techniques is especially important since it allows for obtaining health status without the use of additional sensors. Thermography enables us to reveal additional details, imperceptible in images acquired...
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Neutralising Responsibility: A Critical Analysis of an Airline’s Climate Disclosures
PublicationSustainability reporting provides companies with a medium through which they can communicate their non-financial impacts to stakeholders. The airline industry has been much at the centre of the climate change debate in recent years, which is why it is hardly surprising that airlines seek to take a proactive stance in such reporting. This study critically assesses how an airline based in the Scandinavian region constructs sustainability...
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A Diagnostic Method Based on Deflection Analysis for Monitoring Post-elastic Response of Beams
PublicationA non-destructive diagnostic method based on deflection analysis for monitoring the post-elastic response of beams was developed, and a diagnostic indicator was proposed. The indicator was defined as the second moment of the normalised curvature function about the mid-span, where the curvature was computed from the normalised deflection function. Elastic reference values of the indicator were computed for simply supported beams...
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FEM analysis of composite materials failure in nonlinear six field shell theory
PublicationThe monography deals with the problem of failure initiation in thin laminated composites. Known techniques of laminate structures modelling are briefly characterised. Eventually, shell based approach is chosen for the purpose of the description of the composite structures behaviour, as it predicts their deformation and states of stress effectively in a global sense. The nonlinear six parameter shell theory (6p theory) with asymmetric...
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Thermogravimetric analysis/ pyrolysis of used tyres and waste rubber
PublicationThe process of pyrolysis is investigated in this paper. The pyrolysis results of two samples: waste tyres and rubber at different heating rates (10, 20, 50 K/min), were compared. In other experiments the degradation of two pyrolysis products, char and oil was examined. The kinetic study using the thermogravimetry equipment (TG) was done, which allowed determination of the kinetic mechanism of the process. The elemental analysis...
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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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A model-based approach to analysis of authentication protocols.
PublicationW referacie przedstawiono zintegrowane podejście do analizy protokołów uwierzytelniania o nazwie Object-oriented Formal Authentication Protocol Security Analysis Framework (OF-APSAF). Podejście to jest zaprojektowane na bazie sprawdzonej metody formalnej CSP wraz z narzędziami ją wspierającymi: Casper oraz FDR. Jego integralną częścią jest półformalna zorientowana obiektowo technika modelowania protokołów, ich kontekstu oraz wymagań...
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Thermal analysis of copper(II) complexes of general formula [Et4N]2[CuBrnCl4-n]
PublicationBadano dekompozycję termiczną związków składających sie z anionów: [CuBrnCl4-n]2- (n=0-4) i kationów tetrametyloamoniowych. Stosowano następujące metody badawcze: TG-FTIR, TG-MS, DTA i DTG. Pomiary przeprowadzono w atmosferze argonu i powietrza w zakresie temperatur od 293 K do 1073 K. Produkty dekompozycji identyfikowano metoda spektroskopii w podczerwieni (IR i FIR) oraz metodą dyfrakcji promieniowania rentgenowskiego.
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Topological-numerical analysis of a two-dimensional discrete neuron model
PublicationWe conduct computer-assisted analysis of a two-dimensional model of a neuron introduced by Chialvo in 1995 [Chaos, Solitons Fractals 5, 461–479]. We apply the method of rigorous analysis of global dynamics based on a set-oriented topological approach, introduced by Arai et al. in 2009 [SIAM J. Appl. Dyn. Syst. 8, 757–789] and improved and expanded afterward. Additionally, we introduce a new algorithm to analyze the return times...
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Advanced sensitivity analysis of the impact of the temporal distribution and intensity of rainfall on hydrograph parameters in urban catchments
PublicationKnowledge of the variability of the hydrograph of outflow from urban catchments is highly important for measurements and evaluation of the operation of sewer networks. Currently, hydrodynamic models are most frequently used for hydrograph modeling. Since a large number of their parameters have to be identified, there may be problems at the calibration stage. Hence, sensitivity analysis is used to limit the number of parameters....
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Empirical analyses of robustness of the square Msplit estimation
PublicationThe paper presents Msplit estimation as an alternative to methods in the class of robust M-estimation. The analysis conducted showed that Msplit estimation is highly efficient in the identification of observations encumbered by gross errors, especially those of small or moderate values. The classical methods of robust estimation provide then unsatisfactory results. Msplit estimation also shows high robustness to single gross errors...
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Analysis of Ceramic Elements with Ring-Crack Defects in Lubricated Rolling Contact
PublicationThe 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. Surface ring cracks on lubricating 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 calculations...