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Search results for: COMPOSED SYSTEMS
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Granulometric analysis to etimate influence of anionic surfactrant on activated sludge structure
PublicationThe work concerns the evaluation of the possibility of using laser diffraction analyzer to determine changes in the distribution of sludge floc size in the presence of anionic surfactant. As a model of surfactant linear alkylbenzyne sulphonate (LAS) was used. The granulometric analysis showed that the pure activated sludge was composed of particles with a size of 0,001 to 2 mm. The largest and fastest changes in the distribution...
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Robust identification of quadrocopter model for control purposes
PublicationThe paper addresses a problem of quadrotor unmanned aerial vehicle (so-called X4-flyer or quadrocopter) utility model identification for control design purposes. To that goal the quadrotor model is assumed to be composed of two abstracted subsystems, namely a rigid body (plant) and four motors equipped with blades (actuators). The model of the former is acquired based on a well-established dynamic equations of motion while the...
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On the low-cost design of abbreviated multisection planar matching transformer
PublicationA numerically demanding wideband matching transformer composed of three nonuniform transmission lines (NUTLs) has been designed and optimized at a low computational cost. The computational feasibility of the design has been acquired through the exploitation of low-fidelity NUTL models in most steps of the design procedure and an implicit space mapping optimization engine, providing high accuracy results with only a handful of EM...
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Active Learning Based on Crowdsourced Data
PublicationThe paper proposes a crowdsourcing-based approach for annotated data acquisition and means to support Active Learning training approach. In the proposed solution, aimed at data engineers, the knowledge of the crowd serves as an oracle that is able to judge whether the given sample is informative or not. The proposed solution reduces the amount of work needed to annotate large sets of data. Furthermore, it allows a perpetual increase...
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MODELLING OF CONCRETE FRACTURE AT AGGREGATE LEVEL USING DEM BASED ON X-RAY mu CT IMAGES OF INTERNAL STRUCTURE
PublicationThe paper describes two-dimensional meso-scale numerical results of fracture in notched concrete beams under quasi-static three-point bending. Concrete was modelled as a random heterogeneous 4-phase material composed of aggregate particles, cement matrix, interfacial transitional zones (ITZs) and air voids. As a numerical approach, the discrete element method (DEM) was used. The concrete micro-structure in calculations was directly...
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Mesoscopic simulations of crack propagation in concrete using cohesive elements
PublicationThe paper presents results of two-and three-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 3-phase material composed of aggregate grains placed in the cement matrix with Interfacial Transitional Zones (ITZs) between then. In 2D simulations macro-voids were also taken into account. The particle distribution was taken from real concrete beams...
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A new cold-active β-galactosidase from Arthrobacter sp. S3* - gene cloning, overexpression, purification and properties
PublicationA psychrotrophic bacterium producing a cold-active β-galactosidase was isolated from Spitsbergen soil and classified as Arthrobacter sp. S3*. The gene encoding β-galactosidase was isolated from the genomic DNA library, sequenced, cloned, expressed in Escherichia coli, purified by ion exchange chromatography and characterized. The Arthrobaster sp. S3* β-galactosidase is a homotrimeric enzyme composed of 74,4 kDa subunits. It is...
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Reconstruction of 3D structure of positive corona streamer by local methods
PublicationThe computer algorithms were used for reconstruction of streamer 3D structure. We propose the 3D tree structure model of corona discharge streamer composed with nodes and edges between chosen couples of nodes, which enables easy computation of some important parameters ofstreamers. The 3D model can be derived directly from two projection images by global methods like evolutionary searching or particle simulations. In this paper...
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Rigid finite elements and multibody modelling used in estimation and reduction of rod vibrations
PublicationIn the paper, a mechanical set composed of a robot (manipulator) and of an elastic beam is considered. The beam is fixed to the top of the robot structure. In most of the similar cases, undesired vibrations can be excited in the beam. They are especially significant, when dynamics in the robot braking period is examined. In the paper, estimation and modification of length of the braking period is proposed, in order to reduce the...
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Multistage treatment wetland for treatment of reject waters from digested sludge dewatering
PublicationThe paper presents the influence of sewage composition on treatment in pilot-scale facility for reject waters (RW) from sewage sludge centrifugation. The facility consisted of mechanical (two tanks with 10 d retention each) and biological parts composed of three subsurface flow reed beds working in batch. Two years of monitoring of the facility proved high efficiency removal of predominant pollutants: COD 75–80%, BOD 82.2–95.5%...
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Towards the boundary between easy and hard control problems in multicast Clos networks
PublicationIn this article we study 3-stage Clos networks with multicast calls in general and 2-cast calls, in particular. We investigate various sizes of input and output switches and discuss some routing problems involved in blocking states. To express our results in a formal way we introduce a model of hypergraph edge-coloring. A new class of bipartite hypergraphs corresponding to Clos networks is studied. We identify some polynomially...
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Surgical tool tracking by on-line selection of structural correlation filters
PublicationIn visual tracking of surgical instruments, correlation filtering finds the best candidate with maximal correlation peak. However, most trackers only consider capturing target appearance but not target structure. In this paper we propose surgical instrument tracking approach that integrates prior knowledge related to rotation of both shaft and tool tips. To this end, we employ rigid parts mixtures model of an instrument. The rigidly...
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Development of dynamic method for evaluation of inhibition efficiency on the example of 8-hydroxyquinolin
PublicationSelection of a proper inhibitor should be based on the evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character due to changing physicochemical conditions of the environment and corroding metal surface. Most of actually used methods are stationary or contain assumptions which highly influences obtained values. Development of new dynamic method, based on modified EIS, allows...
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A Linear Phase Filter in Quadruplet Topology With Frequency-Dependent Couplings
PublicationThis letter presents a design of a linear phase microwave bandpass filter. The filter is composed of four resonators arranged in the quadruplet topology. Making the cross and one direct coupling dispersive gives additional design flexibility. The first advantage of using frequency-dependent couplings is the possibility to chose an arbitrary location of a pair of complex transmission zeros (TZs) in the s-domain. The second one is...
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Simplified stability analysis of steel cylindrical silos with corrugated walls and vertical columns
PublicationIn the paper a simplified stability analysis of steel cylindrical silos composed of corru¬gated walls and vertical open-sectional columns was proposed. The whole 3D silo was modeled as a single column resting on elastic foundation provided by the silo walls. In proposed formula for the calculation of the foundation stiffness the curvature of the silo walls was taken into account. Three different analyses were carried out using...
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Rigid finite elements and multibody modeling in analyses of a robot shaped elastic/plastic deformations of a beam
PublicationDynamics analysis of a system composed of a parallel manipulator and of an elastic beam is presented in the paper. Classic 3RRR parallel manipulator is considered and used to deform the beam. Elasto-plastic deformations are investigated. Rigid-finite-elements technique is employed to deal with dynamics of the beam. A multibody structure is associated with the introduced hybrid system in order to model its dynamics. Idea of the...
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Catena-Poly[{[mu]-[eta]5:[eta]5-1-[2-(dimethylamino)ethyl-[kappa]N]cyclopentadienyl}-lithium(I)-([mu]-1,1,3,3-tetra-tert-butyltriphosphane-[kappa]3P2:P1,P3)lithium(I)]
PublicationThe title compound, [Li2(C9H14N)(C16H36P3)]n, is a by-product of the reaction of [Cp(C5H4CH2CH2NMe2)ZrCl2]n with tBu2P-P(SiMe3)Li in toluene. It is a coordination polymer composed of infinite chains running along [010]. One Li(I) atom is chelated by the cyclopentadienyl ring and and the N atom of the scorpionate ligand and a P atom, whereas the other Li(I) atom is coordinated by the backside of the cyclopentadienyl ring and two...
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Identification and non-integer order modelling of synchronous machines operating as generator
PublicationThis paper presents an original mathematical model of a synchronous generator using derivatives of fractional order. In contrast to classical models composed of a large number of R-L ladders, it comprises half-order impedances, which enable the accurate description of the electromagnetic induction phenomena in a wide frequency range, while minimizing the order and number of model parameters. The proposed model takes into account...
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FINITE GROUND CPW-FED UWB ANTENNA OVER THE METALLIC CYLINDRICAL SURFACES
PublicationThe investigation of finite ground coplanar fed ultra-wideband (UWB) antenna and the influence of its curvature and the proximity of circular metallic screen on the reflection coefficients and radiation characteristics is presented. The antenna is composed of two circular coplanar strips which enclose slot aperture of similar shape and is designed on a thin and flexible substrate which allows its bending. The antenna configuration...
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Ionic liquids in the microextraction techniques: the influence of ILs structure and properties
PublicationIonic liquids (ILs) are composed entirely of ions thus they possess unique properties, including negligible volatility, a liquid state in a broad range of temperatures and ability to change them depending on the chosen type of anion and cation, which make ILs unique and useful for many applications in sample preparation techniques. A deeper understanding of the nature of ILs and the impact of their structure on their parameters...
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Inline Microstrip Bandpass Filter With Two Transmission Zeros and Increased Order Using Spurious Resonance of Frequency-Dependent Inverter
PublicationA design method for a class of fourth-order inline microstrip bandpass filter with two transmission zeros and 20% fractional bandwidth is presented. The filter consists of two quarter-wavelength transmission-line resonators coupled by a frequency-dependent inverter. The inverter is composed of two open-ended stubs that are connected by an interdigital capacitor and introduces two poles and two transmission zeros in the filter response....
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Molecular Umbrella as A Nanocarrier for Antifungals
PublicationA molecular umbrella composed of two O‐sulfated cholic acid residues was applied for the construction of conjugates with cispentacin, containing a “trimethyl lock” (TML) or o‐dithiobenzylcarbamoyl moiety as a cleavable linker. Three out of five conjugates demonstrated antifungal in vitro activity against C. albicans and C. glabrata but not against C. krusei, with MIC90 values in the 0.22–0.99 mM range and were not hemolytic. Antifungal...
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Hydrogen Bonds in Blends of Poly(N-isopropylacrylamide), Poly(N-ethylacrylamide) Homopolymers, and Carboxymethyl Cellulose
PublicationRecently, it was reported that the physical crosslinking exhibited by some biopolymers could provide multiple benefits to biomedical applications. In particular, grafting thermoresponsive polymers onto biopolymers may enhance the degradability or offer other features, as thermothickening behavior. Thus, different interactions will affect the different hydrogen bonds and interactions from the physical crosslinking of carboxymethyl...
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Negative result about the construction of genuinely entangled subspaces from unextendible product bases
PublicationUnextendible product bases (UPBs) provide a versatile tool with various applications across different areas of quantum information theory. Their comprehensive characterization is thus of great importance and has been a subject of vital interest for over two decades now. An open question asks about the existence of UPBs, which are genuinely unextendible, i.e., they are not extendible even with biproduct vectors. In other words,...
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Buckling of simplified models of silo with corrugated walls and vertical stiffeners
PublicationThe paper deals with buckling of cylindrical silos composed of corrugated sheets and vertical stiffeners (columns). Comprehensive finite element analyses were carried out for a perfect silo by means of a linear buckling approach. Corrugated walls were simulated as an equivalent orthotropic shell and vertical thin-walled columns as beam elements. Calculations for perfect silos with different numbers of columns made it possible to...
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Proportional-Derivative and Model-Based Controllers for Control of a Variable Mass Manipulator
PublicationIn the paper, numerical analysis of dynamics of a variable mass manipulator is presented. A revolute joints composed manipulator is considered. Payload of the gripper is considered as the only element characterized by unknown value of its mass (variable between subsequent operations). As in other cases of the revolute joints composed manipulators, its behaviour dependents significantly on the pose of the manipulator. When the manipulator...
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Application of the neural networks for developing new parametrization of the Tersoff potential for carbon
PublicationPenta-graphene (PG) is a 2D carbon allotrope composed of a layer of pentagons having sp2- and sp3-bonded carbon atoms. A study carried out in 2018 has shown that the parameterization of the Tersoff potential proposed in 2005 by Ehrhart and Able (T05 potential) performs better than other potentials available for carbon, being able to reproduce structural and mechanical properties of the PG. In this work, we tried to improve the...
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Pollutants removal effectiveness in hydrophyte filters with sequential vertical and horizontal flow
PublicationThe object of investigations was the constructed wetland in Wiedersberg in Saxonia in Germany supplied with domestic sewage from 145 inhabitants. The biological part was composed of sequential reed beds with vertical and horizontal flow of sewage. It in one of new solutions, because up till now configuration with vertical bed situated at front of biological part of treatment was applied.The evaluation of object performance was...
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Buckling Analysis of Cold Formed Silo Column
PublicationThe paper is devoted to stability analysis of different models of steel cold formed silo column. The steel cylindrical silos are often composed of corrugated walls and vertical open-sectional columns uniformly placed along the silo circumference. Both the whole 3D silo, a simplified model consisting of one column with a part of the silo walls, and a single column resting on elastic foundation provided by the silo walls were analyzed....
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Reduction of Tire Rolling Resistance by Optimization of Road Surfaces and Tires
PublicationDuring interaction between tire and road surface three very important phenomena are always in effect. One of them (very desirable) is friction that is important for traction, braking and cornering. Two other phenomena are not desirable at all, that is rolling resistance and noise. This paper discusses relations between road surface and tire parameters versus tire rolling resistance. Road surface texture, porosity, impedance, strength...
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Longitudinally magnetized left-handed cylindrical ferrite coupled line junction for nonreciprocal devices
PublicationThis paper presents investigations of longitudinally magnetized left-handed cylindrical ferrite coupled line junction for nonreciprocal devices. The proposed junction is formed as a quasi periodic arrangement of N unit cells. Each unit cell is realized as a cascade of short cylindrical ferrite coupled lines with reactance circuit composed of series capacitors and parallel inductors. The left-handed cylindrical junction with π/4...
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In uence of Low-Level Features Extracted from Rhythmic and Harmonic Sections on Music Genre Classi cation
PublicationWe present a comprehensive evaluation of the infuence of 'harmonic' and rhythmic sections contained in an audio file on automatic music genre classi cation. The study is performed using the ISMIS database composed of music files, which are represented by vectors of acoustic parameters describing low-level music features. Non-negative Matrix Factorization serves for blind separation of instrument components. Rhythmic components...
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Mathematical model of pennate muscle
PublicationThe purpose of this study is to create a new mathematical model of pennate striated skeletal muscle. This new model describes behaviour of isolated flat pennate muscle in two dimensions (2D) by taking into account that rheological properties of muscle fibres depend on their planar arrangement. A new mathematical model is implemented in two types: 1) numerical model of unipennate muscle (unipennate model); 2) numerical model of...
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Does offshoring affect industry employment? Evidence from a wide European panel countries
Publicationis paper contributes to the literature on the possible impact of international outsourcing on domestic labour markets. We focus on off shoring-employment relationship. Th e analysis is performed for a wide European panel, composed of 27 EU countries and 13 manufacturing sectors, observed in the period 1995-2009. Th anks to the use of input-output tables from the WIOD project, we measure the intensity of off shoring in the sectors,...
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Dynamic soil improvement by hybrid technologies
PublicationHybrid method of subsoil improvement for road embankment foundation is described. This method is composed of two wellknown methods: dynamic replacement (DR) and microblasting (DDC) one (Deep Dynamic Compaction). The method was used for both the strengthening of the fully saturated organic subsoil as well as for acceleration of the consolidation of the organic layers. The practice ensures the expected results. A proper example on...
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Bioactive core material for porous load-bearing implants
PublicationSo far state of knowledge on biodegradable materials is reviewed. Among a variety of investigated materials, those composed of polymers and ceramics may be considered as only candidates for a core material in porous titanium alloy. The collagen and chitosan among natural polymers, polyhydroxy acids among synthetic polymers, and hydroxyapatite and tricalcium phosphate among ceramics are proposed for further research. Three essential...
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Frequency-dependent coupling model for microwave band-pass filter
PublicationThe goal of this work was to create a circuit model which represents frequency-dependent coupling between microwave resonators. Our models are designed for in-line filters. The frequency-dependent coupling enables one to realize a transmission zero which is not possible in classical approach with frequency independent inverters. In addition, the proposed model allows us to observe out-of-band behavior, e.g. spurious resonance....
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THE INTERACTION BETWEEN STEEL COLUMN CHORD AND CLOSELY SPACED REINFORCEMENT.
PublicationNowadays, more often than before, civil engineering designers are willing to use steel build-up members composed of single or doubled cold-formed chords interconnected using different mechanical connectors. This paper subject is an analysis of cooperation of a closely spaced built-up cold-formed chord interconnected with series of bolts that are located along the length of the member in a specific spacing. This distance along the...
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Numerical modelling of 3D printout using line (1D) elements
PublicationA proposition of some numerical modelling of the 3D printout is presented in the paper. The proposed model is composed of some 1D elements. The resulting numerical model of the infill consist of beam, spring and rigid elements. Obtained results confirm correctness of the proposed modelling method. Two methods of estimation of the spring parameters are proposed in the paper. In the first method, mechanical properties of the connecting...
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Correlation between natural frequencies and buckling load in a stiffened shell
PublicationThe paper deals with correlation between natural frequencies and buckling load of a stiffened shell composed of corrugated sheets and vertical stiffeners (columns). The simplified shell segment represents the buckling behaviour of a whole silo with sparsely distributed columns. The paper covers variants of linear buckling anal-yses, dynamic eigenvalue analyses and geometrically non-linear analyses of a segment modelled with shell...
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Detection of moving objects in images combined from video and thermal cameras
PublicationAn algorithm for detection of moving objects in video streams from the monitoring cameras is presented. A system composed of a standard video camera and a thermal camera, mounted in close proximity to each other, is used for object detection. First, a background subtraction is performed in both video streams separately, using the popular Gaussian Mixture Models method. For the next processing stage, the authors propose an algorithm...
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Generalized Chebyshev Bandpass Filters With Frequency-Dependent Couplings Based on Stubs
PublicationThis paper presents an accurate synthesis method for inline and cross-coupled generalized Chebyshev bandpass filters with frequency-dependent couplings implemented via open and short stubs. The technique involves the synthesis of a lumped-element prototy pe in the form of a coupling matrix with a frequency-dependent term and the conversion of this prototype to a distributed-element mode l composed of sections of TEM lines. This...
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Effectiveness of toluene separation from gas phase using supported ammonium ionic liquid membrane
PublicationAmmonium ionic liquids (ILs) are relatively cheap in synthesis and environmentally benign and despite that they have been very rarely used in gas separation. In this research we used several ammonium ILs as liquid membranes for removal of residual toluene from gas phase. Ionic liquids used in this study were composed of bis(trifluoromethylsulfonyl)imide anion [Tf2N] and trimethylbutylammonium [N1114], trietylbutylammonium [N2224],...
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Visualization of a lifeboat motion during lowering along ship’s side
PublicationThis paper presents description of a computer program for motion visualization of a lifeboat lowered along ship’s side. The program is a post-processor which reads results of numerical calculations of simulated objects’ motions. The data is used to create scene composed of 3D surfaces to visualize mutual spatial positions of a lifeboat, ship’s side and water waving surface. Since the numerical data contain description of a simulation...
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Biological properties of chitosan/Eudragit E 100 and chitosan/poly(4-vinylpyridine) coatings electrophoretically deposited on AgNPs-decorated titanium substrate
PublicationThe objective of the study was the determination of the response, in contact with human osteoblast-like MG-63 cells, of electrophoretically deposited coatings composed of chitosan (CS), Eudragit E 100 (EE100), or poly(4- vinylpyridine) (P4VP) on a silver nanoparticle (AgNPs)-decorated titanium substrate. Before deposition, the substrate was coated with silver by electro-reduction of silver nitrate. The coatings deposition was carried...
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Modification of structured bio‑carbon derived from spongin-based scaffolds with nickel compounds to produce a functional catalyst for reduction and oxidation reactions: Potential for use in environmental protection
PublicationThree different 3D fibrous-like NiO/Ni(OH)2/Ni‑carbonized spongin-based materials were prepared via a simple sorption–reduction method. Depending on the support used, the catalysts were composed of carbon, nickel oxide, nickel hydroxide and zero-valent nickel, with the surface content of the nickel-containing phase in the range 15.2–26.0 wt%. Catalytic studies showed promising activity in the oxidation of phenolic compounds in water...
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Single-phase power electronics transformer with active functions for smart grid
PublicationThis paper presents the control of one cell of a modular single-phase power electronics transformer with active functions for meeting the smart grid concept. In this way, the converter could be used not only as a conventional transformer but also for grid such as reactive power, harmonic elimination and energy storage. The topology of the cell is composed by a bidirectional converter with three stages: a half bridge in the input...
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Flood Classification in a Natural Wetland for Early Spring Conditions Using Various Polarimetric SAR Methods
PublicationAbstract--- One of the major limitations of remote sensing flood detection is the presence of vegetation. Our study focuses on a flood classification using Radarsat-2 Quad-Pol data in a natural floodplain during leafless, dry vegetation (early spring) state. We conducted a supervised classification of a data set composed of nine polarimetric decompositions and Shannon entropy followed by the predictors' importance estimation to...
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Two-dimensional simulations of concrete fracture at aggregate level with cohesive elements based on X-ray lCT images
PublicationThe paper presents results of two-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 4-phase material composed of aggregate grains placed in the cement matrix, interfacial transitional zones (ITZs) and macro-voids. The particle distribution was taken from real concrete beams on the basis of X-ray lCT images. Comprehensive numerical analyses were carried...
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Study on polymer modified road asphalt mixture
PublicationThe formulation of ternary asphalt-additives blend composed of crumb rubber : low-density polyethylene (CR : LDPE) and crumb rubber : textile fiber (CR : TF) couples, and quaternary asphalt additives-blend composed of (CR : LDPE : TF) triplets on the virgin asphalt to optimize the asphalt basic and rheological properties and to use the extrusion process of two or three additives to obtain composite materials of them, as well as...