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Search results for: DIRECT SAMPLE ANALYSIS
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Evaluation of Nanoporous Carbon Synthesized from Direct Carbonization of a Metal–Organic Complex as a Highly Effective Dye Adsorbent and Supercapacitor
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Particulate Emissions from European Vehicles Featuring Direct Injection Spark Ignition Engines Tested Under Laboratory Conditions
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Comparison of sono-direct and sono-alternate current electro-coagulation processes for removal of color and turbidity from domestic wastewater
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Neutrocyte-to-lymphocyte ratio predicts the presence of a replicative hepatitis C virus strand after therapy with direct-acting antivirals
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Direct measurements of odorous volatile organic compounds present in biosolids cakes by Proton Transfer Reaction – Mass Spectrometry Technique
PublicationThis paper show the results of investigation of concentration of odorous chemical compounds emitted upon ageing of anaerobically stabilised biosolids that could contribute to the overall odour character of nuisance emissions. Biosolids samples from wastewater treatment plant were collected in spring time. Concentrations of volatile organic compounds using a US EPA flux hood and Proton Transfer Reaction-Time of Flight-Mass Spectrometry...
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Deep eutectic solvent (DES) with silver nanoparticles (Ag-NPs) based assay for analysis of lead (II) in edible oils
PublicationThis paper presents an application of silver nanoparticles impregnated by Deep Eutectic Solvents (DES) as ultrasonication aided microextraction system for lead (II) determination in edible oils. The paper presents a systematic optimization of method parameters and examples of its application for analysis of real samples. Maximum recovery for lead (II) extraction was obtained for choline chloride and phenol with a 1:2 molar ratio....
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ANALYSIS OF BRACE STIFFNESS INFLUENCE ON STABILITY OF THE TRUSS
PublicationThe paper is devoted to the numerical and experimental research of stability of a truss with side elastic supports at the top chord. The structure is a model of a real roof truss scaled by factor ¼. The linear buckling analysis and non-linear static analysis were carried out. The buckling length factor for the compressed top chord was calculated and the limit load for the imperfect truss shell model with respect to brace stiffness...
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Dynamic mechanical thermal analysis of polyamide 6/thermoplastic polyurethane blends
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Authentication of whisky due to its botanical origin and way of production by instrumental analysis and multivariate classification methods
PublicationHeadspacemass-spectrometry (HS-MS), mid infrared (MIR) and UV–vis spectroscopywere used to authenticate whisky samples from different origins and ways of production ((Irish, Spanish, Bourbon, TennesseeWhisky and Scotch). The collected spectra were processed with partial least-squares discriminant analysis (PLS-DA) to build the classification models. In all cases the five groups ofwhiskieswere distinguished, but the best resultswere...
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Flow Analysis of a Kaplan Turbine
PublicationThis monograph is a guide to a method of experimental and numerical flow investigations for Kaplan - type turbines. The numerical calculations were compared with the test results of the model Kaplan turbine. The tests were carried out on the model test rig in the Gdańsk University of Technology. The turbine has been thoroughly experimentally investigated, resulting in the identification of optimum setting combination of the stator...
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Corrosion monitoring by harmonic analysis in aqueous environments
PublicationThis paper presents tests concerning the rate of corrosion in non-alloy steel (type S235JR) in an aqueous environment, with an additive of sodium chloride by means of polarization resistance measurements and harmonic analysis. The tests have been carried out for steel samples exposed to the testing environment for six weeks, in order to obtain a constant rate of corrosion in the function of time. The measurements have aimed at...
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The use of Markov chains in the social convergence analysis
PublicationThe main goal of this article is to analyze the social convergence process using Markov chains. In this research, term social convergence refers to the reduction of dispersion in the standard of living among countries. The use of Markov chains in the social convergence analysis allowed describing movements of observational units within the distribution and providing more details about the mechanism of the convergence process. A...
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Example of tension fabric structure analysis
PublicationThe aim of the work is to examine two variants of non-linear strain-stress relations accepted to description of architectural fabric. Discussion on the fundamental equations of the dense net model, used in description of coated woven fabric behaviour is presented. An analysis of tensile fabric structures subjected to the dead load and initial pretension is described.
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3D buckling analysis of a truss with horizontal braces
PublicationThe present research is devoted to the study of out-of-plane buckling of a truss with horizontal braces. The truss is a model of real roof truss scaled by factor ¼. A linear buckling and a non-linear analysis with geometric and material nonlinearity were carried out. The truss buckling and limit load for different stiffnesses and number of braces are found. Numerical analysis are verified by experiment. Threshold bracing stiffness...
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Functional Safety Analysis including Human Factors
PublicationIn this paper selected aspects of human factors are discussed that should be taken into account during the design of safety-related functions for a complex hazardous installation and its protections. The layer of protection analysis (LOPA) methodology is used for simplified risk analysis based on defined accident scenarios. To control the risk the safety instrumented functions (SIFs) are identified and their safety integrity levels...
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A Survey on Identifying and Addressing Business Analysis Problems
PublicationDespite the growing body of knowledge on requirements engineering and business analysis, these areas of software project are still considered problematic. The paper focuses on problems reported by business analysts and on applicability of available business analysis techniques as solutions to such problems. A unified set of techniques was developed on the basis of 3 industrial standards associated with IIBA, REQB and IREB certification...
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Uncertainty analysis of measuring system for instantaneous power research
PublicationThe paper presents a metrological analysis of the measurement system used for diagnosis of induction motor bearings, based on the analysis of the instantaneous power. This system was implemented as a set of devices with dedicated software installed on a PC. A number of measurements for uncertainty estimation was carried out. The results of the measurements are presented in the paper. The results of the aforementioned analysis helped...
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Sentiment Analysis of Facebook Posts:the Uber case
PublicationThis article analyses the sentiment of opinions, i. e. its classification as phrases with a neutral, positive and negative emotional tone. Data used as a basis for the analysis were opinions expressed by Facebook users about Uber and collected in the period between July 2016 and July 2017. The primary objective of the study was to obtain information about the perceptions of Uber over thirteen consecutive months. The study confirms...
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PLANNING AND ANALYSIS OF EARTHQUAKE DISASTER RELIEF WORK IN ETHIOPIA
PublicationThis paper addresses dynamic planning and analysis of earthquake disaster relief work by analysis the disaster throughout the technical and procedural method. And combine this analysis as continues assessment for better input to investigating planning disaster for discontinuous economic growth. This implemented, considering the vulnerability and hazard analysis as a procedural analysis disaster to estimating acceptance risk leveling...
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Thermal and dynamic mechanical analysis of cross-linked poly(esterurethanes)
PublicationW pracy przedstawiono wyniki badań termograwimetrycznych oraz termomechanicznych usieciowanch za pomocą styrenu i metakrylanu metylu poli(estrouretanów). Uzyskane wyniki pozwoliły stwierdzić, że stabilność termiczna poli(estrouretanów) jest wystarczająca do wielu zastosowań technicznych. Przeprowadzone analizy wykazały również, iż polimery sieciowane styrenem wykazują separację fazową.
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Thermal analysis and static strength of polyurethanes obtained from glycolysates
PublicationPrzeprowadzono analizę termiczną i zbadano właściwości wytrzymałościowe poliuretanów otrzymanych z glikolizatów o różnej budowie chemicznej. Glikolizaty pozyskiwano w procesie recyklingu surowcowego odpadów poliuretanowych o niskiej gęstości. Środkiem glikolizującym był propano-1,3-diol. Poliuretany z glikolizatów syntezowano metodą prepolimerową z MDI i BDO jako przedłużacza łańcuchów. Nie stosowano katalizatorów.
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FE analysis of reinforced concrete corbels with enhanced continuum models
PublicationW artykule pokazano wyniki MES symulacji wsporników żelbetowych. Zachowanie wsporników modelowano przy zastosowaniu 3 różnych modeli betonu: sprężysto-plastycznego, degradacji sprężystej i rozmytych rys. Modele rozszerzono o długość mikrostruktury przy zastosowaniu teorii nielokalnej. Wyniki numeryczne porównano z doświadczeniami z literatury.
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Structure analysis and thermal degradation characteristics of bio-based poly(propylene succinate)s obtained by using different catalyst amounts
PublicationLinear bio-based polyester polyols were prepared with the use of succinic acid and 1.3-propanediol (both with natural origin). As a catalyst was used tetraisopropyl orthotitanate (TPT). In order to determine the effect of various catalyst content on the thermal degradation characteristics, three different TPT amounts, as a 1.3-propanediol equivalent, were used, namely 0.1 mass% (PPS-0.1), 0.2 mass% (PPS-0.2) and 0.25 mass% (PPS-0.25)....
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3D Buckling Analysis of a Truss with Horizontal Braces
PublicationThe present research is devoted to the study of out–of–plane buckling of a truss with horizontal braces. The truss is a model of real roof truss scaled by factor 1=4. A linear buckling and a non–linear analysis with geometric and material non–linearity were carried out. The truss buckling and limit load for different stiffnesses and number of braces are found. Numerical analysis are verified by experiment. Threshold bracing stiffness condition...
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GIS Solution for Weather Forecast Data Analysis
PublicationIn this paper authors present the GIS system for the analysis of the numerical weather prediction data. This kind of data has multidimensional character (three dimensions and time) and its analysis should consider all the available factors. Proposed GIS system consists of RASDAMAN application with implemented OLAP cube mechanism, which enables the user to process data in the spatial-time domain. It also simplifies the meteorological...
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Analysis of Historic Brick Walls' Strengthening Methods
PublicationAnalysis of the behavior of historical brick walls is difficult and complicated. However, computer calculations are being increasingly used in the evaluation of cultural heritage buildings and some of their elements. The aim of this paper is to analyze the historic brick walls reinforcement. Different methods of strengthening are compared and discussed. Numerical analysis, based on finite element method, was conducted on the assumption...
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Exhaled breath analysis by resistive gas sensors
PublicationBreath analysis has attracted human beings for centuries. It was one of the simplest methods to detect various diseases by using human smell sense only. Advances in technology enable to use more reliable and standardized methods, based on different gas sensing systems. Breath analysis requires the detection of volatile organic compounds (VOCs) of the concentrations below individual ppm (parts per million). Therefore, advanced detection...
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Using Synchronously Registered Biosignals Dataset for Teaching Basics of Medical Data Analysis – Case Study
PublicationMedical data analysis and processing strongly relies on the data quality itself. The correct data registration allows many unnecessary steps in data processing to be avoided. Moreover, it takes a certain amount of experience to acquire data that can produce replicable results. Because consistency is crucial in the teaching process, students have access to pre-recorded real data without the necessity of using additional equipment...
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Detection and time/frequency analysis of electric fields in the ground
PublicationThis paper sets out to detect and characterize electric fields in the ground (such as stray current fields) using a tandem time/frequency method of signal analysis. Results were obtained from investigations performed in the presence of a generated electric field with controlled variable characteristics, and in the presence of an electric field generated by a tramline. The analysis of measurement registers was performed using Short‐Time...
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A LABORATORY STAND FOR THE ANALYSIS OF DYNAMIC PROPERTIES OF THERMOCOUPLES
PublicationIn the present elaboration, problems connected with measurements of high variable temperatures of gases are introduced and the impact of dynamic properties of different construction solutions of thermoelements on the accuracy of the measurements is considered. A laboratory stand built within research under doctoral thesis, destined for analysis of dynamic properties of thermocouples is also described. Results of numerical simulation...
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Export diversification and economic development: a dynamic spatial data analysis
PublicationThis paper contributes to the empirical literature on the relationship between ‘export variety’ (export diversification) and economic development by relaxing the assumption of cross-country independence and allowing for spatial diffusion of shocks in observed and unobserved factors. Export variety is measured for a balanced panel of 114 countries (1992-2012) using very detailed information on their exports (HS 6-digit product...
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Multimodal Particle Swarm Optimization with Phase Analysis to Solve Complex Equations of Electromagnetic Analysis
PublicationIn this paper, a new meta-heuristic method of finding roots and poles of a complex function of a complex variable is presented. The algorithm combines an efficient space exploration provided by the particle swarm optimization (PSO) and the classification of root and pole occurrences based on the phase analysis of the complex function. The method initially generates two uniformly distributed populations of particles on the complex...
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Analytical applications of smartphones for agricultural soil analysis
PublicationSoil is one of the most important farming resources. Appropriate managing of its quality promotes productive and sustainable agriculture. The valuable farm practice in soil quality managing is based on regular soil analysis with the aim to determine the exact amount of nutrients or other chemical, physical and biological soil properties. Soil analysis usually requires samples collection at desired sampling depth following by samples...
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NON-LINE ANALYSIS OF STIFFNESS IN COMPRESSION CONDITIONS
PublicationThe analyzes were aimed at demonstrating the influence of parameters describing the deformation of the structure on the uncertainty of critical force, and the impact of technological imperfections on stress uncertainty in compression conditions. In a linear buckling analysis, the problem is considered only for the initial, permanent state of the stiffness matrix. In the case of demonstrating the influence of initial deformations...
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Detection of the Bee Queen Presence Using Sound Analysis
PublicationThis work describes the system and methods of data analysis we use for beehive monitoring. We present overview of the hardware infrastructures used in hive monitoring systems and we describe algorithms used for analysis of this kind of data. Based on acquisited signals we construct the application that is capable to detect an absence of honey bee queen. We describe our method of signal analysis and present results that allow us...
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Analysis of degaussing process of ferromagnetic objects
PublicationResults of the analytical and numerical analysis of the degaussing process phenomena of ferromagnetic objects were presented in this paper. The screening effectiveness of the electromagnetic field of magnetic screens in most cases depends on thickness, conductivity, magnetic permeability of the screen and angular frequency of degaussing currents. The magnetic field inside thin-layer ferromagnetic object was presented in this paper....
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Usage of concentrated spectrogram for analysis of acoustical signals
PublicationA novel precise method of signal analysis in the time-frequency domain is presented. A signal energy distribution is estimated by discard and displacement of energy parts of the classical spectrogram. A channelized instantaneous frequency and a local group delay are used in order to energy replacement. Additionally, newly introduced representations such as: a channelized instantaneous bandwidth and a local group duration are used...
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Macromodeling techniques for accelerated finite element analysis
PublicationThis paper deals with the Model Order Reduction applied locally in the Finite Element Method (FEM) analysis. Due to the reduction process, blocks of FEM system matrices associated with selected subregions of the computational domain are projected onto the subspaces spanned by the vectors of suited orthogonal projection basis. In effect, large and sparse FEM matrices are replaced with small and dense ones, called macromodels. This...
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A novel hybrid adaptive framework for support vector machine-based reliability analysis: A comparative study
PublicationThis study presents an innovative hybrid Adaptive Support Vector Machine - Monte Carlo Simulation (ASVM-MCS) framework for reliability analysis in complex engineering structures. These structures often involve highly nonlinear implicit functions, making traditional gradient-based first or second order reliability algorithms and Monte Carlo Simulation (MCS) time-consuming. The application of surrogate models has proven effective...
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Modal analysis of a steel grandstand
PublicationAmong the issues related to the idea of sustainable society is the safety of civil engineering structures devoted to satisfy different needs of people. One of the types of structures devoted to satisfy recreational needs are grandstands, which are used during sport events or music concerts. It is obligatory to consider interaction between structure and crowd load especially when the crowd movement involves rhythmic jumping, dancing,...
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Differential analysis of dynamic immittance spectra
PublicationThis work presents a new approach to the analysis of immittance spectrograms of systems characterised by non-stationarity. The possibility of linking the evolution of the immittance response with changes in the parameters describing the system is achieved by introducing a spectrum in differential form. By using the above procedure, it becomes possible to separate elements with a dependence (or lack thereof) from an independent...
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Numerical analysis of crack propagation in silicone nitride
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. 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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Diagnostic Analysis of Exhaust Gas with A Quick-Changing Temperature from a Marine Diesel Engine Part II / Two Factor Analysis
PublicationThe article presents a continuation of research carried out to determine the effect of input parameters (changes in engine structure parameters) on selected output parameters (diagnostic measures), based on quickly changing exhaust gas temperature. A method of determining the simultaneous influence of two input factors (the structure parameter and the engine load) on one output factor was presented, as well as an evaluation...
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Application of the DSC analysis of thermoplastic polyurethane elastomers to a comparative study of their technological properties
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Failure analysis and modernization of high-pressure hydraulic press for drilling tubes testing
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Analysis of Interspike-Intervals for the General Class of Integrate-and-Fire Models with Periodic Drive
PublicationWe study one-dimensional integrate-and-fire models of the general type x˙=F (t, x) and analyze properties of the firing map which iterations recover consecutive spike timings. We impose very week constraints for the regularity of the function F (t, x), e.g. often it suffices to assume that F is continuous. If additionally F is periodic in t, using mathematical study of the displacement sequence of an orientation preserving circle...
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Experimental and numerical analysis of the modified TB32 crash tests of the cable barrier system
PublicationRoad restraint systems, including safety barriers, are one of the means used to improve road safety. Currently, they can be allowed to general use after passing the specific crash tests. However, it is always important and desirable to evaluate their performance under various realistic conditions, which can happen on the roads. In this study, the behaviour of the cable barrier system in impact conditions different than assumed...
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Direct use of point clouds in real-time interaction with the cultural heritage in pandemic and post-pandemic tourism on the case of Kłodzko Fortress
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Rapid and sensitive determination of acrylamide in potato crisps using reversed-phase direct immersion single drop microextraction-gas chromatography
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Direct QSPR: the most efficient way of predicting organic carbon/water partition coefficient (log K OC) for polyhalogenated POPs
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