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Search results for: VOLUME-DELAY FUNCTION
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Equivalence of equicontinuity concepts for Markov operators derived from a Schur-like property for spaces of measures
PublicationVarious equicontinuity properties for families of Markov operators have been – and still are – used in the study of existence and uniqueness of invariant probability for these operators, and of asymptotic stability. We prove a general result on equivalence of equicontinuity concepts. It allows comparing results in the literature and switching from one view on equicontinuity to another, which is technically convenient in proofs....
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The difficult heritage. The reuse of former prison buildings
PublicationIn recent years, there has been a trend to reuse abandoned buildings. Adaptive re-use allows preservation of the original structure and implements a new function to it. Such activity could help to preserve the historic value of buildings; moreover, many other advantages can be found in educational, ecological and economic fields. However, the question arises of whether every object can be freely adapted. This article examines the...
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The propagation of the waves in the CTO S.A. towing tank
PublicationThe paper presents the results of research focused on the wave propagation in the CTO S.A. deepwater towing tank. In the scope of paper, the wavemaker transfer function was determined for regular waves, based on the Biésel Transfer Function and further for irregular waves, based on Hasselman model of nonlinear energy transfer. The phenomena: wave damping, wave breakdown and wave reflection, were measured, analyzed and mathematically...
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Radioisotope measurements of the liquid-gas flow in the horizontal pipeline using phase method
PublicationThe paper presents application of the gamma-absorption method to a two-phase liquid-gas flow investigation in a horizontal pipeline. The water-air mixture was examined by a set of two Am-241 radioactive sources and two NaI(Tl) scintillation probes. For analysis of the electrical signals obtained from detectors the cross-spectral density function (CSDF) was applied. Results of the gas phase average velocity measurements for CSDF...
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Stability of softly switched multiregional dynamic output controllers with a static antiwindup filter: A discrete-time case
PublicationThis paper addresses the problem of model-based global stability analysis of discrete-time Takagi–Sugeno multiregional dynamic output controllers with static antiwindup filters. The presented analyses are reduced to the problem of a feasibility study of the Linear Matrix Inequalities (LMIs), derived based on Lyapunov stability theory. Two sets of LMIs are considered candidate derived from the classical common quadratic Lyapunov...
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Distributed representation of information on cyclic events
PublicationA representation of information on cyclic events has been proposed which is advantageous for computing environments where a distributed set of Receivers reacts to cyclic events generated by distributed sources. In such scenario no immanent central information repository exist on event timing or volume. Receivers are able to learn the event cycles without communicating with each other, merely on the basis of the fact that an event...
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Performance of the flat plate solar collector operated with water-Al2O3 nanofluid
PublicationThis paper shows the experimental results of the performance a flat plate solar collector with water-Al2O3 nanofluid as a working fluid. The weight fractions of nanoparticles were 0.1%, 0.2% and 0.4%. The volume flow rate of nanofluid varied from 60 l/h to 170 l/h. The results show that application of nanofluids instead of pure water resulted in higher efficiency of the tested flat plate solar collector for given range of thermal...
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Automatic Analysis System of TV Commercial Emission Level
PublicationThe purpose of the study was to determine whether the commercial emission level is higher than the emission level of a regular program and to check if the commercials broadcasters follow the recommended levels of loudness. The paper shortly reviews some chosen methods of volume measurements specified in the ITU and EBU recommendations. Then, it describes a prototype of a system implemented in Embarcadero C++ Builder 2010 which...
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Modeling Volunteer Based Systems
PublicationThere are two main approaches to processing tasks requiring high amounts of computational power. One approach is using clusters of mostly identical hardware, placed in dedicated locations [1, 2, 3]. The other approach is outsourcing computing resources from large numbers of volunteers connected to the Internet [7]. This chapter presents an application of a mathematical model of the volunteer computing presented in Volume 1 of this...
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Multianalyte Calibration Methods for Potentiometric Integrated Sensors System for Determination of Ions Concentration in a Body Fluids
PublicationIn recent years, integration and miniaturization of ion-selective electrodes (ISEs) have brought many benefits resulting in the possibility of simultaneous determination of the ions concentration in a small sample volume. One of the key problems related to the preparation of integrated sensors systems (ISSs) is a calibration procedure due to the necessity to calibrate each particular sensor separately. The main aim of the research...
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New Design of Axial Piston Pump with Displaced Swash Plate Axis of Rotation for Hydro-Mechanical Transmissions
PublicationThis paper presents a prototype design of an axial piston pump with displaced swash plate axis of rotation in two directions of discharge with electronic control intended for installation on a hydraulic-mechanical gearbox dedicated to working machines. The effect of displacement of the swash plate rotation axis on dead space volume and volumetric efficiency is presented. The construction and principle of operation of the capacity...
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Acoustic Processor of the MCM Sonar
PublicationThis paper presents the concept of an acoustic processor of the mine countermeasure sonar. Developed at the Department of Marine Electronics Systems, Gdansk University of Technology, the acoustic processor is an element of the MG-89, a modernised underwater acoustic station. The focus of the article is on the modules of the processor. They are responsible for sampling analogue signals and implementing the algorithms controlling...
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QoS Extensions for Flow-Awareness Networks
PublicationThe paper contains a description and research results of the proposal for distributed QoS extensions for Flow-Based Networking. These QoS extensions let the network accept or reject flows based on current network load and QoS promises for each of the flows. Proposed solution consists of two distributed components, each of them performing in every node, measurement system and access control. The solution could be applied in any...
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The unstable thermoelectric effect in non-stoichiometric Cu2Se during the non-equilibrium phase transition
PublicationThe superionic α ↔ β phase transition in Cu1.96Se thermoelectric material is investigated by means of thermal analysis (DSC) and measurements of Seebeck coefficient and electrical conductivity. Results of the DSC measurements with 1–10 K/min heating and cooling rates show that the material is close to the equilibrium phase composition during the transformation. However, the kinetic limitation of the process exists, which is indicated...
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Measurement of Impulse Response of Shallow Water Communication Channel by Correlation Method
PublicationPerformances of underwater acoustic communication (UAC) systems are strongly related to specific propagation conditions of the underwater channel; conditions that can additionally change in time due to the movement of the acoustic system transmitter and receiver or to reflection by underwater objects of the transmitted signal. The time-varying impulse response is a comprehensive description of dynamically changing transmission...
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The Influence of Stretch Rod Speed on the Relationship between Preblown Bottle Aesthetic Quality and Final Blown Bottle Thickness Profile in Stretch Blow Molding from Preform Process
PublicationFrom a mechanical point of view, the aesthetic quality of preblown PET bottles and thickness profile of final blown PET bottles manufactured in ISBM process are determined by mechanical and thermal response of blown preforms. From the microscopic point of view the biggest influence on the mechanical and thermal properties of PET bottles have orientation and crystallization processes. From a technological point of view, the aesthetic...
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Dew Formation and Chemistry Near a Motorway in Poland
PublicationIn this study, the influence of traffic intensity on dewformation efficiency and chemistry is presented. The measurementswere conducted near the A4 motorway in SW Poland in almost flatland relief with intense agricultural activity. The dew/hoarfrost wascollected by means of insulated plain passive radiative condensersat three sites: AN and AS located in the close vicinity of themotorway (30 m) on the opposite sides of the road,...
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Solvation of ionic liquids based on N-methyl-N-alkyl morpholinium cations in dimethylsulfoxide – volumetric and compressibility studies
PublicationThe density and sound velocity of the 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-octyl-morpholinium bis(trifluoromethanesulfonyl)imide and N-decyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide in dimethylsulfoxide were measured at T = (298.15 to 318.15)...
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Role of quantitative chest perfusion computed tomography in detecting diabetic pulmonary microangiopathy
PublicationAims: Aimof the study was to determine the role of perfusion chest computed tomography(pCT) in evaluation of pulmonary diabetic angiopathy.Methods: 18 never-smoking patients (10 diabetic patients and 8 healthy controls) underwentchest high resolution CT (HRCT) and then pCT scanning. In both groups, blood tests,biochemical analysis, fibrinogen, HbA1c, spirometry, diffusion capacity for carbonmonoxide(DLCO) and body pletysmography...
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Optimization of vortex-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction for quantification of niclosamide in real samples
PublicationIn this manuscript, a green and fast vortex-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction (VA-HMDES-DLPME) method was developed for the selective extraction and determination of niclosamide in read samples, including rice, medicine tablets, and water samples. Here, hydrophobic magnetic deep eutectic solvents were used as the extracting solvent without requiring any centrifugation...
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An optimal designed experiment for the alkaline hydrolysis of feather keratin
PublicationFeathers, burdensome waste from the poultry industry, can be a cheap source of keratin, a protein with excellent physico- chemical, biological, and mechanical properties. Acid and alkaline hydrolyses are usually adopted for isolation of keratin from its natural resources. This study aimed at assessing the statistically significant effect of input variables in the alkaline hydrolysis of keratin from chicken feathers on the process...
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Optical fiber aptasensor for label-free bacteria detection in small volumes
PublicationHighly sensitive devices for fast bacteria detection are sought to be developed with the task of quantifying the worldwide problem of pathogenic bacteria and thus helping to take control over spreading bacterial infections. This work concerns a sensing solution based on microcavity in-line Mach-Zehnder interferometer (μIMZI) induced in an optical fiber. Such a device exhibits ultrahigh sensitivity to refractive index changes...
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Influence of lightweight structures used in swimming pools and water parks objects on their functionality, building form and spatial-visual effects indoors.
PublicationSpeaking about architecture of swimming facilities and water parks we have in mind their form, function , design and detail, texture and color. A particularly important element of the architecture of these buildings was and still is the structure.
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Evaluation of the Macro- and Micro-Economic Factors Affecting the Financial Energy of Households
PublicationThis paper is an evaluation of the common macro-economic, micro-economic, and social factors affecting households’ financial situations. Moreover, the author’s objective was to develop a fuzzy logic model for forecasting fluctuations in the number of nonperforming consumer loans in a country using the example of Poland. This study represents one of the first attempts in the global literature to develop such a forecasting model...
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On Dynamic Boundary Conditions Within the Linear Steigmann-Ogden Model of Surface Elasticity and Strain Gradient Elasticity
PublicationWithin the strain gradient elasticity we discuss the dynamic boundary conditions taking into account surface stresses described by the Steigmann–Ogden model. The variational approach is applied with the use of the least action functional. The functional is represented as a sum of surface and volume integrals. The surface strain and kinetic energy densities are introduced. The Toupin–Mindlin formulation of the strain gradient elasticity...
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Infrastruktura ładowania pojazdów elektrycznych
PublicationW artykule przedstawiono przegląd zagadnień z zakresu infrastruktury ładowania pojazdów elektrycznych. Przeanalizowano wpływ dużej liczby pojazdów EV na system elektroenergetyczny. W analizie uwzględniono zarówno wzrastające zapotrzebowanie na moc jak też na zapewnienie wysokiej jakości energii elektrycznej. Pokazano ideę wykorzystania pojazdów EV jako magazynów energii w systemie elektroenergetycznym. Zaprezentowano podstawowe...
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Electro-thermal buckling of elastically supported double-layered piezoelectric nanoplates affected by an external electric voltage
PublicationPurpose Thermal buckling of double-layered piezoelectric nanoplates has been analyzed by applying an external electric voltage on the nanoplates. The paper aims to discuss this issue. Design/methodology/approach Double-layered nanoplates are connected to each other by considering linear van der Waals forces. Nanoplates are placed on a polymer matrix. A comprehensive thermal stress function is used for investigating thermal buckling....
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Global Complex Roots and Poles Finding Algorithm Based on Phase Analysis for Propagation and Radiation Problems
PublicationA flexible and effective algorithm for complex roots and poles finding is presented. A wide class of analytic functions can be analyzed, and any arbitrarily shaped search region can be considered. The method is very simple and intuitive. It is based on sampling a function at the nodes of a regular mesh, and on the analysis of the function phase. As a result, a set of candidate regions is created and then the roots/poles are verified...
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Shape Optimisation of Kaplan Turbine Blades Using Genetic Algorithms
PublicationThis monograph is a comprehensive guide to a method of blade profile optimisation for Kaplan-type turbines. This method is based on modelling the interaction between rotor and stator blades. Additionally, the shape of the draft tube is investigated. The influence of the periodic boundary condition vs. full geometry is also discussed. Evolutionary algorithms (EA) are used as an optimisation method together with artificial neural...
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Classifying the transformation products (TPs) of emerging contaminants (ECs) for prioritizing research into their impact on the environment and human health
PublicationOne of the first books to cover transformation products, rather than primary compounds, Transformation Products of Emerging Contaminants in the Environment gathers, specifies, synthesizes, and advances existing knowledge of the most important transformation product (TPs) of the main groups of emerging contaminants with potential concern to human health and the environment. This two-volume set for researchers and professionals covers...
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Speech Intelligibility Measurements in Auditorium
PublicationSpeech intelligibility was measured in Auditorium Novum on Technical University of Gdansk (seating capacity 408, volume 3300 m3). Articulation tests were conducted; STI and Early Decay Time EDT coefficients were measured. Negative noise contribution to speech intelligibility was taken into account. Subjective measurements and objective tests reveal high speech intelligibility at most seats in auditorium. Correlation was found between...
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VOF-DEM-FEM combined model of the reef breakwater collapse
PublicationZespolony model numeryczny (metoda modelowania przepływu ze swobodną powierzchnią rozdziału faz ciekłej i gazowej w siatce nieruchomej (ang. Volume of Fluid - VOF, metoda elementów dyskretnych (ang. Distinct Element Method, metoda elementów skończonych (MES)) został wykorzystany do zbadania odkształceń falochronu narzutowego i jego piaszczystego podłoża w wyniku oddziaływania falowania powierzchniowego. Wyniki analizy numerycznej...
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Digitalization Process and Its Impact on Economic Growth A Panel Data Study for Developing Countries
PublicationThis book analyses the impact of Information and Communication Technologies (ICTs) on economic development. It contains theoretical and empirical studies, including panel studies on various issues facing developing countries, such as education, corruption, economic growth, government expenditure, financial inclusion, foreign direct investment, infrastructure, economic and social welfare, and inequality. Each chapter offers a well-conceived...
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Young’s modulus distribution in the FEM models of bone tissue
PublicationThis paper presents how differences of Young’s modulus in adjacent finite elements typical for organic materials such as bone tissue, influence stress calculating. Emphasizing high computational cost of variable Young’s modulus in parts of the model, where the number of finite elements has been raised, the authors wants to prove that new model of finite element which has variable Young’s modulus in its volume needs to be created....
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Simulation of the remanence influence on the transient states in a single-phase multiwinding transformer
PublicationThis paper presents the mathematical model of a single-phase multi-winding core type transformer taking into account magnetic hysteresis phenomenon based on the feedback Preisach model (FPM). The set of loop differential equations was developed for a K-th winding transformer model where the flux linkages of each winding includes flux Φ common to all windings as a function of magneto motive force Θ of all windings. The first purpose...
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Second-order Stark effect and polarizability of a relativistic two-dimensional hydrogenlike atom in the ground state
PublicationThe second-order Stark effect for a planar Dirac one-electron atom in the ground state is analyzed within the framework of the Rayleigh-Schrödinger perturbation theory, with the use of the Sturmian series expansion of the generalized Dirac-Coulomb Green's function. A closed-form analytical expression for the static dipole polarizability of that system is found. The formula involves the generalized hypergeometric function ${}_{3}F_{2}$...
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A high-accuracy method of computation of x-ray waves propagation through an optical system consisting of many lenses
PublicationThe propagation of X-ray waves through an optical system consisting of many X-ray refractive lenses is considered. Two differential equations are contemplated for solving the problem for electromagnetic wave propagation: first – an equation for the electric field, second – an equation derived for a complex phase of an electric field. Both equations are solved by the use of a finite-difference method. The simulation error is estimated...
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SFEM Analysis of Beams with Scaled Lengths including Spatially Varying and Cross-Correlated Concrete Properties
PublicationThis paper presents the results obtained for plain concrete beams under four-point bending with spatially varying material properties. Beams of increasing length but constant depth were analyzed using the stochastic finite element method. Spatial fluctuation of a uniaxial tensile strength, fracture energy and elastic modulus was defined within cross-correlated random fields. The symmetrical Gauss probability distribution function...
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Impact of rotor geometry optimization on the off-design ORC turbine performance
PublicationThe paper describes the method of CFD based Nelder-Mead optimization of a 10 kW single-stage axial turbine operating in an ORC system working on R7100. The total-to-static isentropic efficiency is defined as an objective function. Multi-point linear regression is carried out to determine the significance of the objective function arguments and to pick up the set of particular variables and characteristic quantities (e.g. flow angles)...
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Clinical anatomy of the spatial structure of the right ventricular outflow trac
PublicationBackground. The right ventricular outflow tract (RVOT) is located above the supraventricular crest and reaches the level of the pulmonary valve. Detailed knowledge of the RVOT spatial structure and its morphology is extremely important for cardiac invasive therapeutic procedures. Objectives. To examine the spatial structure of the RVOT using virtual models of the right ventricle (RV) interior obtained post mortem. Material and...
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Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction Using Deep Eutectic Solvents (DESs) for Neutral Red Dye Spectrophotometric Determination
PublicationDeep eutectic solvents (DES), which have low toxicity and are low cost, biodegradable, and easily synthesized, were used for the extraction of neutral red (NR) dye before its spectrophotometric analysis. DES, containing choline chloride as a hydrogen bond acceptor and phenol as a hydrogen bond donor with a molar ratio of 1:2, was used for the extraction of NR dye from aqueous media. The possible interaction of different DESs with...
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Morphology and internal structure of small-scale washovers formed in the coastal zone of the semi-enclosed tideless basin, Gulf of Gdańsk, Baltic Sea
PublicationThis study explores the morphological features and internal structure of small-scale washovers along the southeastern Baltic Sea coast, providing insights into these most widespread yet often neglected deposits in the recent research of geomorphological and sedimentary record of storm surges. A 15-year-long record of morphological changes of the coast was acquired from regional orthophotos to analyse their geometry and spatial...
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Engineering TADF, Mechanochromism, and Second Harmonic Up- conversion Properties in Regioisomeric Substitution Space
PublicationThis research article explores the distinct TADF efficiency of three donor-acceptor based regio-isomers: DPAOCN (ortho- isomer), DPAMCN (meta-isomer), and DPAPCN (para-isomer). DPAPCN exhibits maximum TADF efficiency in both solution and solid-state with an impressive reverse inter-system crossing (RISC) rate of ~ 106 s-1; the underlying cause being the minimum singlet-triplet splitting energy or ∆EST and maximum SOC (spin-orbit...
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A Self-Equalized Waveguide Filter With Frequency-Dependent (Resonant) Couplings
PublicationThis letter presents a design of a fifth-order linear phase filter with frequency-dependent couplings. The filter is composed of a triplet that is directly coupled to two resonators at the input and output. To provide group delay flattening a cross-coupling in the trisection has a strongly dispersive character with a negative slope parameter. To achieve this, an E-plane stub with a septum was used. To further improve the filter...
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Investigation of the 16-year and 18-year ZTD Time Series Derived from GPS Data Processing
PublicationThe GPS system can play an important role in activities related to the monitoring of climate. Long time series, coherent strategy, and very high quality of tropospheric parameter Zenith Tropospheric Delay (ZTD) estimated on the basis of GPS data analysis allows to investigate its usefulness for climate research as a direct GPS product. This paper presents results of analysis of 16-year time series derived from EUREF Permanent Network...
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Time versus space trade-offs for randezvous in trees
PublicationTwo identical (anonymous) mobile agents start from arbitrary nodes of an unknown tree and have to meet at some node. Agents move in synchronous rounds: in each round an agent can either stay at the current node or move to one of its neighbors. We consider deterministic algorithms for this rendezvous task. The main result of this paper is a tight trade-off between the optimal time of completing rendezvous and the size of memory...
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Simulation model for evaluation of packet sequence changed order of stream in DiffServ network
PublicationCurrent packet networks use a large variety of mechanisms which should support QoS (Quality of Service). One of those mechanisms is routing (calculating connection paths for incoming service requests). The most effective mechanism in QoS context is dynamic routing, which is based on the current network state described by the offered traffic matrix and link states. After switching between calculated available paths, connection...
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High-Speed Binary-to-Residue Converter Design Using 2-Bit Segmentation of the Input Word
PublicationIn this paper a new approach to the design of the high-speed binary-to-residue converter is proposed that allows the attaining of high pipelining rates by eliminating memories used in modulo m generators. The converter algorithm uses segmentation of the input binary word into 2-bit segments. The use and effects of the input word segmentation for the synthesis of converters for five-bit moduli are presented. For the number represented...
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Representation of magnetic hysteresis in tape wound core using feedback Preisach model
PublicationThis paper presents a mathematical model for the hysteresis phenomenon in ferromagnetic tape wound core. The feedback scalar Preisach model of hysteresis is used to simulate magnetic behavior of the grain oriented silicon strip of ET114-27 type. Determination of B-H hysteretic curve is based on measurement of the initial magnetization curve and the main hysteresis loop. The Preisach distribution function (PDF) of ET114-27 material...
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Arm EMG Wavelet-Based Denoising System
PublicationThese paper presents research results of muscle EMG signal denoising. In the same time two muscles were examined - an adductor muscle (biceps brachii) and an abductor muscle (tricpeps brachii). The EMG signal was filtered using the wavelet transform technique, having selected the crucial parameters as: wavelet basis function (Daubechies 4), 10 th decomposition level, threshold selection algorithm (Heurestic) and a sln rescaling...