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Search results for: Statistical time series methods
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Complex Monitoring of the Coastal Cliffs on the Example of Cliff in Jastrzebia Gora, Poland
PublicationThe cliff coasts, which are in total about 100 km long, are especially vulnerable to abrasion. The mean regression of the studied object which is the seacliff in Jastrzebia Gora depends on time. For example, from 1875 to 1937 the cliff regress 90 m in mean pace of 1.4 meter a year. Besides of natural factors causing the degradation, there is also an anthropogenic activity, which speeds up the abrasion process. Based on these informations,...
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Estimation of a Stochastic Burgers' Equation Using an Ensemble Kalman Filter
PublicationIn this work, we consider a difficult problem of state estimation of nonlinear stochastic partial differential equations (SPDE) based on uncertain measurements. The presented solution uses the method of lines (MoL), which allows us to discretize a stochastic partial differential equation in a spatial dimension and represent it as a system of coupled continuous-time ordinary stochastic differential equations (SDE). For such a system...
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Weather Hazard Avoidance in Modeling Safety of Motor-Driven Ship for Multicriteria Weather Routing
PublicationWeather routing methods find the most suitable ocean?s route for a vessel, taking into account changeable weather conditions and navigational constraints. In the multicriteria approach based on the evolutionary SPEA algorithm one is able to consider a few constrained criteria simultaneously. The approach applied for a ship with hybrid propulsions has already been presented by one of the authors on previous TransNav?2009. This time...
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Problemy modernizacji szpitali
PublicationStale dokonujący się rozwój technologii medycznych oraz postęp w możliwościach leczniczych w sposób zasadniczy wpływa na kształt szpitala. W obecnie realizowanych szpitalach maleje powierzchnia działów pielęgnacji chorych, natomiast zwiększa się powierzchnia działów diagnostyczno-zabiegowych. Skraca się średni czas pobytu pacjenta w szpitalu. Szpital staje się sprawną „maszyną” do diagnozowania, a następnie leczenia pacjenta w...
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Comparative analysis of switched reluctance motor control algorithms
PublicationПредмет исследования. Развитие микропроцессорной техники и силовой электроники позволило создавать недорогие и эффективные системы управления различными электромеханическими объектами, которые ранее широко не использовались из-за сложности управления. К таким устройствам можно отнести вентильно-индукторные электрические машины. Данные машины широко применяются в различных практических разработках, например, в тяговом электроприводе,...
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Comparative analysis of switched reluctance motor control algorithms
PublicationПредмет исследования. Развитие микропроцессорной техники и силовой электроники позволило создавать недорогие и эффективные системы управления различными электромеханическими объектами, которые ранее широко не использовались из-за сложности управления. К таким устройствам можно отнести вентильно-индукторные электрические машины. Данные машины широко применяются в различных практических разработках, например, в тяговом электроприводе,...
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Interactions of protons with furan molecules studied by collision-induced emission spectroscopy at the incident energy range of 50–1000 eV
PublicationInvestigations of the ion-molecule reactions provide insight into many fields ranging from the stellar wind interaction with interstellar media, up to medicine and industrial applications. Besides the applications, the understanding of these processes is itself a problem of fundamental importance. Thus, interactions of protons with the gas-phase furan molecules have been investigated for the first time in the energy range of 50–1000...
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Semicrystalline Polyesters Based on a Novel Renewable Building Block
PublicationIsohexides, like e.g. isosorbide, are well-known carbohydrate-based rigid diols which are capable of dramatically increasing the glass transition temperature of polyesters. However, their relatively low reactivity has thus far hampered large-scale industrial applications in the polymer field. Recently, with the aim to increase reactivity while at the same time retain rigidity, we have developed a new isoidide dicarboxylic acid...
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Unique agreement of experimental and computational infrared spectroscopy: a case study of lithium bromide solvation in an important electrochemical solvent
PublicationInfrared (IR) spectroscopy is a widely used and invaluable tool in the studies of solvation phenomena in electrolyte solutions. Using state-of-the-art chemometric analysis of a spectral series measured in a concentration-dependent manner, the spectrum of the solute-affected solvent can be extracted, providing a detailed view of the structural and energetic states of the solvent molecules influenced by the solute. Concurrently,...
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Structural and luminescent study of TeO2-BaO-Bi2O3-Ag glass system doped with Eu3+ and Dy3+ for possible color-tunable phosphor application
PublicationTellurite glass systems of 73TeO2-4BaO-3Bi2O3-1Ag:xEu2O3-(2-x)Dy2O3 (where x = 0.5, 1, 1.5, 2 in molar ratio) composition have been successfully synthesized. In order to acquire Ag nanoparticles, materials have been heat treated at 350 °C in the air atmosphere. Structural properties of obtained samples were evaluated with various techniques. X-Ray Diffraction (XRD) measurements indicated that obtained materials are amorphous in...
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Cost-Effective and Sufficiently Precise Integration Method Adapted to the FEM Calculations of Bone Tissue
PublicationThe technique of Young’s modulus variation in the finite element is not spread in biomechanics. Our future goal is to adapt this technique to bone tissue strength calculations. The aim of this paper is to present the necessary studies of the element’s integration method that takes into account changes in material properties. For research purposes, a virtual sample with the size and distribution of mechanical properties similar...
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Machine learning approach to packaging compatibility testing in the new product development process
PublicationThe paper compares the effectiveness of selected machine learning methods as modelling tools supporting the selection of a packaging type in new product development process. The main goal of the developed model is to reduce the risk of failure in compatibility tests which are preformed to ensure safety, durability, and efficacy of the finished product for the entire period of its shelf life and consumer use. This kind of testing...
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Predicting Performance of Lightweight Concrete with Granulated Expanded Glass and Ash Aggregate by Means of Using Artificial Neural Networks
PublicationLightweight concrete (LWC) is a group of cement composites of the defined physical, mechanical, and chemical performance. The methods of designing the composition of LWC with the assumed density and compressive strength are used most commonly. The purpose of using LWC is the reduction of the structure’s weight, as well as the reduction of thermal conductivity index. The highest possible strength, durability and low thermal conductivity...
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GNSS reference solution for permanent sition stability monitoring and geodynamical investigations - the ASG-EUPOS case study
PublicationThe aim of this paper is to present the strategy of determination of the reference solution for the ASG-EUPOS (ActiveGeodetic Network – European Position Determination System) coordinate monitoring system. ASG-EUPOS is a network of permanent GNSS (Global Navigation Satellite System) stations controlled by the Polish Head Office of Geodesy and Cartography (HOGC), which main role is to realize the ETRS89 (European Terrestrial Reference...
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Dekodowanie kodów iterowanych z użyciem sieci neuronowej
PublicationNadmiarowe kody iterowane są jedną z prostych metod pozyskiwania długich kodów korekcyjnych zapewniających dużą ochronę przed błędami. Jednocześnie, chociaż ich podstawowy iteracyjny dekoder jest prosty koncepcyjnie oraz łatwy w implementacji, to nie jest on rozwiązaniem optymalnym. Poszukując alternatywnych rozwiązań zaproponowano, przedstawioną w pracy, strukturę dekodera tego typu kodów wspomaganą przez sieci neuronowe. Zaproponowane...
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Molecular identification and genotyping of Staphylococci: genus, species, strains, colnes, lineages, and interspecies exchanges
PublicationStaphylococci are increasingly recognized as etiological agents of many opportunistic human and animal infections, emphasizing the need for a rapid and accurate identification, even to a genotypical level of these bacteria. In the recent years, there has been a significant progress in typing and phylogenetic study of Staphylococcus species. Here, we describe molecular methods used in taxonomy as well as staphylococci characterization....
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Testing Stability of Digital Filters Using Optimization Methods with Phase Analysis
PublicationIn this paper, novel methods for the evaluation of digital-filter stability are investigated. The methods are based on phase analysis of a complex function in the characteristic equation of a digital filter. It allows for evaluating stability when a characteristic equation is not based on a polynomial. The operation of these methods relies on sampling the unit circle on the complex plane and extracting the phase quadrant of a function...
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Detection of Bioactive Compounds in Organically and Conventionally Grown Asparagus Spears
PublicationIn the recent reports, there are contradictory conclusions about the nutritional and health properties of organic and conventionally growing vegetables. We hypothesized that organic cultivation system results in higher quality of asparagus (Asparagus officinalis L.) because of organic manure and effective organisms. Therefore, new analytical methods were applied in order to find the differences in bioactive compounds between the...
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Visually validated semi-automatic high-frequency oscillation detection aides the delineation of epileptogenic regions during intra-operative electrocorticography
PublicationOBJECTIVE: To test the utility of a novel semi-automated method for detecting, validating, and quantifying high-frequency oscillations (HFOs): ripples (80-200 Hz) and fast ripples (200-600 Hz) in intra-operative electrocorticography (ECoG) recordings. METHODS: Sixteen adult patients with temporal lobe epilepsy (TLE) had intra-operative ECoG recordings at the time of resection. The computer-annotated ECoG recordings were visually...
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Simulating propagation of coherent light in random media using the Fredholm type integral equation
PublicationStudying propagation of light in random scattering materials is important for both basic and applied research. Such studies often require usage of numerical method for simulating behavior of light beams in random media. However, if such simulations require consideration of coherence properties of light, they may become a complex numerical problems. There are well established methods for simulating multiple scattering of light (e.g....
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Badanie i analiza efektywności alokacji strumieni danych w heterogenicznej sieci WBAN
PublicationW niniejszej dysertacji doktorskiej poddano dyskusji efektywność alokacji strumieni danych w heterogenicznej radiowej sieci WBAN (Wireless Body Area Networks). Biorąc pod uwagę dynamiczny rozwój nowoczesnych sieci radiokomunikacyjnych piątej generacji (5G), którego część stanowią radiowe sieci działające w obrębie ciała człowieka, bardzo ważnym aspektem są metody maksymalizujące wykorzystanie dostępnych zasobów czasowo –częstotliwościowych...
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Use of structural equation modeling in quantitative research in the field of management and economics: A bibliometric analysis in the systematic literature review
PublicationPURPOSE: This paper aims to provide a comprehensive review of scholarly research focusing on using quantitative methods and particularly structural equation modeling (SEM) in management and economics studies, as well as provide a bibliometric agenda including the time horizon of individual publications, the highest citation rate, geographic and industry areas, methodological context, and keywords. METHODOLOGY: A systematic literature...
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Rapid Assays for Specific Detection of Fungi of Scopulariopsis and Microascus Genera and Scopulariopsis brevicaulis Species
PublicationPurpose Fungi of Scopulariopsis and Microascus genera cause a wide range of infections, with S. brevicaulis being the most prevalent aetiological agent of mould onychomycosis. Proper identification of these pathogens requires sporulating culture, which considerably delays the diagnosis. So far, sequencing of rDNA regions of clinical isolates has produced ambiguous results due to the lack of reference sequences in publicly available...
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Performance analysis of mobility protocols and handover algorithms for IP-based networks
PublicationA rapid growth of IP-based networks and services has created the vast collection of resources and functionality available to users by means of a universal method of access - an IP protocol. At the same time, advances in design of mobile electronic devices have allowed them to reach utility level comparable to stationary, desktop computers, while still retaining their mobility advantage. Following this trend multiple extensions...
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Degradation of the Concrete Railway Track Bed Located in the Vicinity of the Loading Wharf
PublicationThe following article describes the damages of the concrete railway track bed at the place of unloading petroleum products located in the immediate vicinity of the cargo berth. The concrete of the track bed has been a subject to degradation as a result of many years of exploitation resulting, inter alia, in its cyclical flooding of petroleum products during the unloading and loading of rail tankers. Repairs carried out in the previous...
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Analiza wyników monitoringu odbieraków prądu w warunkach ruchowych na linii kolejowej
PublicationOmówiono metodę ciągłego monitorowania stanu odbieraków prądu na linii kolejowej w oparciu o pomiar uniesienia przewodów jezdnych sieci trakcyjnej w czasie przejazdu pociągu. Omówiono zasadę działania wdrożonego stanowiska monitoringu. Opisano algorytmy analizy danych pomiarowych - w szczególności oszacowania siły statycznej odbieraka prądu - i przyjęte kryteria oceny odbieraka. W analizie bierze się pod uwagę także prędkość pociągu...
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INFLUENCE OF MEASURING CONDITIONS ON TYRE/ROAD NOISE
PublicationA decisive factor for the development of tyres and road surfaces is the ability to conduct representative and reproducible measurements of selected characteristics related to the interaction of tyres and road surfaces. In terms of tyre/road noise measurements in Europe two methods described in ISO/FDIS 11819-2 and ECE Regulation No.117 are used. The latter is compulsory for assigning the tyre noise labels. The methodologies differ...
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Structural motifs in the Cu(II), Mn(II) and Zn(II) complexes based on N,N,N-donor dipodal or N,N,N,N-donor tripodal ligands obtained in situ: Synthesis, crystal structures and xanthine oxidase inhibition properties
PublicationA series of four novel transition metal complexes, [Cu(NCS)2L1] (1), [Mn(NCS)2L1] (2) where L1 = bis(1-(3,5-dimethylpyrazolyl)methyl)amine, [Mn(NCS)2L2] (3) and [Zn(NCS)L2]2[Zn(NCS)4] (4) where L2 = tris(1-(3,5-dimethylpyrazolyl)methyl)amine, has been obtained in situ by a one-step, one-pot synthetic path starting from 1-hydroxymethyl-3,5-dimethylpyrazole (L). The isolated complexes were fully characterised by elemental analysis,...
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Structure and the space vector modulation for a medium-voltage power-electronic-transformer based on two seven-level cascade H-bridge inverters
PublicationThis study presents the structure and the space vector pulse-width modulation (SVPWM) for power electronic transformer (PET) based on two seven-level cascade H-bridge (CHB) inverters. The DC links of CHB inverters are coupled with nine dual-active bridge (DAB) converters with medium-frequency transformers. The DC-link voltages are equalised with two methods – through the control of DAB voltages...
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Modelling Signalised Intersections Reliability of Functioning
PublicationThe article addresses a fundamental aspect of traffic, i.e. the operation of traffic signals at intersections, in reference to the reliability theory. In many cases, when intersections carry substantial amounts of traffic, selecting control parameters to produce satisfactory traffic conditions is quite difficult. Design methods do not cover all possible situations which are the result of intersection geometry and location...
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Adaptive system for recognition of sounds indicating threats to security of people and property employing parallel processing of audio data streams
PublicationA system for recognition of threatening acoustic events employing parallel processing on a supercomputing cluster is featured. The methods for detection, parameterization and classication of acoustic events are introduced. The recognition engine is based onthreshold-based detection with adaptive threshold and Support Vector Machine classifcation. Spectral, temporal and mel-frequency descriptors are used as signal features. The...
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Ground lemon and stevia leaves as renewable functional fillers with antioxidant activity for high-density polyethylene composites
PublicationThe development of new sustainable material solutions in the processing of thermoplastic polymers concerns both the application of biopolymers and the use of valorized plant derivatives as fillers and modifiers of petrochemical polymers. Herein, the possibility of using unprocessed raw parts of two commonly used in the food industry leaves, i.e., lemon (LL) and stevia (ST), as active and functional fillers for high-density polyethylene...
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Thermodynamic, Anticoagulant, and Antiproliferative Properties of Thrombin Binding Aptamer Containing Novel UNA Derivative
PublicationThrombin is a serine protease that plays a crucial role in hemostasis, fibrinolysis, cell proliferation, and migration. Thrombin binding aptamer (TBA) is able to inhibit the activity of thrombin molecule via binding to its exosite I. This 15-nt DNA oligonucleotide forms an intramolecular, antiparallel G-quadruplex structure with a chair-like conformation. In this paper, we report on our investigations on the influence of certain...
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LS-DYNA simulations of the impacts of a 38-ton Heavy Goods Vehicle into a road cable barrier
PublicationNowadays, more and more attention is being paid to safety on roads and motorways. It is due to the continuous development of road and motorway network and a significant increase of the number of vehicles on roads. To meet the expectations of improving road safety in Poland, the Road Innovations Development (RID) research programme was implemented in 2016. The aim of the RID 3A - Road Safety Equipment (RoSE) project is a comprehensive...
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Thermal utilization of meat and bone meals. Performance analysis in terms of drying process, pyrolysis and kinetics of volatiles combustion
PublicationA development of technology of thermal utilization requires a thorough knowledge of the physicochemical properties, as well as kinetics of combustion of volatiles and char. Due to waste management regulations the meat and bone meal (MBM) is regarded as biofuel constituting one of the alternatives to fossil fuels in the energy market. MBM is a heterogeneous material that may consist of several different fractions. The extensive...
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Degradation of ferritic X10CrAlSi18 stainless steel caused by slurry
PublicationThe slurry erosion tests of ferritic X10CrAlSi18 steel were carried out using a slurry pot device. In order to investigate the erosion process, two series of tests were performed: first one with a constant impact velocity of 5 m/s, 7 m/s and 9 m/s and the second one, during which the impact velocity was changed after every exposure. During each test, an influence of test conditions on volume loss, surface hardness and roughness...
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Experimental and Numerical Investigation of Mechanical Properties of Lightweight Concretes (LWCs) with Various Aggregates
PublicationHigh requirements for the properties of construction materials and activities directed at environment protection are reasons to look for new solutions in concrete technology. This research was directed at solutions affecting the reduction of energy consumption and CO2 emissions. The use of lightweight concretes (LWCs) allows one to meet both conditions at the same time. The purpose of the research presented in this paper was to...
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Evaluation of high-frequency roughness measurement errors for composite and ceramic surfaces after machining
PublicationPrecise characterisation of surface topography is of the greatest importance since many factors directly affect the accuracy of the whole measurement process. In this paper, the variety of surface topographies from machined composite and ceramic workpieces was studied with a special emphasis on the measurement results. Surfaces were subjected to the ground diamond, honing and milling processes. Measurement results were analysed...
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Autistic Employees’ Technology-Based Workplace Accommodation Preferences Survey—Preliminary Findings
PublicationBackground: There has been an increase in the number of research studies focused on the design of accommodations aimed at improving the well-being and work performance of autistic employees. These accommodations took various forms; some of them were based on modification of management practices, for example, support in the area of effective communication, or involved modifications to the physical working environment aimed at limiting...
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Detection of the First Component of the Received LTE Signal in the OTDoA Method
PublicationIn a modern world there is a growing demand for localization services of various kinds. Position estimation can be realized via cellular networks, especially in the currently widely deployed LTE (Long Term Evolution) networks. However, it is not an easy task in harsh propagation conditions which often occur in dense urban environments. Recently, time-methods of terminal localization within the network have been the focus of attention,...
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Privacy-Preserving, Scalable Blockchain-Based Solution for Monitoring Industrial Infrastructure in the Near Real-Time
PublicationThis paper proposes an improved monitoring and measuring system dedicated to industrial infrastructure. Our model achieves security of data by incorporating cryptographical methods and near real-time access by the use of virtual tree structure over records. The currently available blockchain networks are not very well adapted to tasks related to the continuous monitoring of the parameters of industrial installations. In the database...
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ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT
PublicationThe possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections...
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Hybridization of the FDTD method with use of the discrete Green's function
PublicationIn this contribution, a hybrid technique is presented which combines the finite-difference time-domain (FDTD) method and the discrete Green's function (DGF) formulation of this method. FDTD is a powerful technique for the analysis of complex penetrable objects but its application is not efficient when the computational domain includes many free-space cells. Therefore, the hybrid method was developed which is applicable to complex...
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Electricity demand prediction by multi-agent system with history-based weighting
PublicationEnergy and load demand forecasting in short-horizons, over an interval ranging from one hour to one week, is crucial for on-line scheduling and security functions of power system. Many load forecasting methods have been developed in recent years which are usually complex solutions with many adjustable parameters. Best-matching models and their relevant parameters have to be determined in a search procedure. We propose a hybrid...
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Multi-sensor monitoring of the corrosion rate and the assessment of the efficiency of a corrosion inhibitor in utility water installations
PublicationThis paper presents an implementation of the monitoring of the corrosion rate and the assessment of the efficiency of a corrosion inhibitor in a utility water installation using an automated corrosion monitoring system. Due to the fact that the corrosion inhibitor was added to water intended for human consumption, it was necessary to build a multi-sensor monitoring system. In order to implement corrosion monitoring using a linear...
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Algorithms for testing security in graphs
PublicationIn this paper we propose new algorithmic methods giving with the high probability the correct answer to the decision problem of security in graphs. For a given graph G and a subset S of a vertex set of G we have to decide whether S is secure, i.e. every subset X of S fulfils the condition: |N[X] \cap S| >= |N[X] \ S|, where N[X] is a closed neighbourhood of X in graph G. We constructed a polynomial time property pseudotester based...
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Computer-assisted assessment of learning outcomes in the laboratory of metrology
PublicationIn the paper, didactic experience with broad and rapid continuous assessment of students’ knowledge, skills and competencies in the Laboratory of Metrology, which is an example of utilisation of assessment for learning, is presented. A learning management system was designed for manage, tracking, reporting of learning program and assessing learning outcomes. It has ability to provide with immediate feedback, which is used by the...
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Comparative analysis of IP-based mobility protocols and fast handover algorithms in IEEE 802.11 based WLANs
PublicationA rapid growth of IP-based networks and services created the vast collection of resources and functionality available to users by means of an uniform method of access - an IP protocol. At the same time, advances in design of mobile electronic devices allowed them to reach utility level comparable to stationary, desktop computers, while still retaining their mobility advantage. Unfortunately, the base IP protocol does not perform...
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Green aspects of techniques for the determination of pesticides in fruits and vegetables
PublicationApplied all over the world, pesticides are some of the most dangerous pollutants of the environment because of their stability, mobility, their ability to accumulate in the environment and their consequent long-term adverse effects on living organisms in general and human health in particular. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical...
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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...