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Antimicrobial resistance of fecal indicators in muncipal wastewater treatment plant
PublicationAntimicrobial resistance of fecal coliforms (n = 153) and enterococci (n = 199) isolates was investigated in municipal wastewater treatment plant (WWTP) based on activated sludge system. The number of fecal indicators (in influent and effluent as well as in the aeration chamber and in return activated sludge mixture) was determined using selective media. Susceptibility of selected strains was tested against 19 (aminoglycosides,...
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The influence of food phytochemicals on cyclic phosphodiesterase 4 (PDE4) activity
PublicationCyclic phosphodiesterase 4 (PDE4) belongs to family of cyclic phosphodiesterases, which are expressed predominantly in inflammatory cells, airway smooth muscles, cardiovascular tissues and brain. Inhibitors of this family of enzymes found medicinal applications as antidepressants, antiinflamatory drugs (mainly in airway diseases) or antiasthmatics (Ibudilast). PDE4 inhibitors are also being tested for preventing the development...
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BIODIVERSITY OF YEASTS ISOLATED FROM CAVES OF THE POLISH TATRA MOUNTAINS, AND ITS BIOTECHNOLOGICAL POTENTIAL
PublicationMost of the Earth’s biosphere is permanently or periodically exposed to temperatures below 5°C. Cold habitats harbor a wide diversity of psychrophiles. For many years Antarctica has been the geographic area preferred for studying the diversity and properties of cold-adapted microorganisms. However, the non-Antarctic habitats like Himalayas or Alps are also extensively explored. The Tatra Mountains are Europe’s second-highest massif...
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Impact response of two-layered grouted aggregate fibrous concretecomposite under falling mass impact
PublicationTwo-layered Grouted Aggregates Fibrous Concrete Composite (TGAFCC) is a new category concrete which became popular recently and attracted the attention of researchers globally. Recent studies indicated that TGAFCC has notable improvement in mechanical properties, which has been sufficiently documented. However, the impact behaviour of TGAFCC when combined with Glass Fibre Mesh (GFM) and Textile Fibre Mesh (TFM) is still unexplored....
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The microbial community, its biochemical potential, and the antimicrobial resistance of Enterococcus spp. in Arctic lakes under natural and anthropogenic impact (West Spitsbergen)
PublicationThe sustainable management of small human communities in the Arctic is challenging. In this study, both a water supply system (Lake 1) under the natural impact of a bird-nesting area, and a wastewater receiver (Lake 2) were analysed in the vicinity of the Polish Polar Station on West Spitsbergen. Microbial community composition, abundance and activity were assessed in samples of the treated wastewater, lake water and sediments...
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The dependence of linear viscoelasticity limits of cold-recycled mixtures on time of curing and compaction method
PublicationCold-recycled mixtures are currently among the most widely used and investigated methods that enable recycling of old pavement structures in an environmentally friendly manner. Upon milling, the old pavement structure – whose gradation can be improved with addition of virgin aggregate – is mixed and compacted at ambient temperature. The main binding agents are bituminous emulsion and cement. Due to their dual binding behaviour,...
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Pilot study of the influence of thermoplastic starch based polymer packaging material on the growth of diatom population in sea water environment
PublicationNovel polymeric packaging materials susceptible to environmentally friendly decomposition appeared on the global market. The paper is devoted to an investigation of the impact of degradable polymer packaging on marine life. The chosen polymer was a commercial packaging based on thermoplastic starch (TPS over 85%). The microorganism chosen was Phaeodactylum tricornutum diatom (identified in many aquatic reservoirs, with a tendency...
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Elektrochemiczny czujnik na bazie cieczy jonowej do oznaczania par benzaldehydu
PublicationW pracy przedstawiono prototypowy, laboratoryjny, elektrochemiczny czujnik do oznaczania par benzaldehydu w argonie. Cieczą jonową testowaną jako elektrolit i środowisko reakcji redox była: bis(trifluorometylosulfonylo)imidek 1-butylo,3-metyloimidazolinowy ([BMIM][Tf2N]). W pomiarach użyto komercyjnych elektrod firm: DropSens Co. i BVT Technologies. Walidacji poddano dwa parametry metrologiczne czujnika: granicę wykrywalności i...
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Measurements of transmission properties of Acoustic Communication Channels
PublicationTough transmission properties of shallow water acoustic channels (SWAC) highly limit the use of underwater acoustic communication (UAC) systems. An adaptive matching of modulation and signaling schemes to instantaneous channel conditions is needed for reliabledata communications. This creates, however, unique challenges for designers when compared to radio transmission systems. When communication system elements are in move, the...
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Application of Maximum Lenght Sequence in Silent Sonar
PublicationSilent sonars are designed to reduce the distance over which their sounding pulses can be detected by intercept sonars. In order to meet this objective, we can use periodical sounding signals that have low power, a very long duration and wide spectrum. If used in the silent sonar's receiver, matched filtration ensures very good detection of motionless or slow moving targets. However, it is more difficult to detect echo signals...
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Alternative diagnostic method applied on marine diesel engines having limited monitoring susceptibility
PublicationThe paper presents a method of technical state evaluation of working spaces of a marine diesel engine at the limited control susceptibility. The method foresees making a diagnosis of the engine's working spaces on the basis of measurements of the exhaust gas pressure in the channels connecting engine cylinders with the turbocharger's turbine. Diagnostic measurements are carried out at representative (comparative) steady loads depending...
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Influence of a lipid bilayer on the conformational behavior of amphotericin B derivatives - A molecular dynamics study.
PublicationAmphotericin B (AmB) is an effective but very toxic antifungal antibiotic. In our laboratory a series of AmB derivatives of improved selectivity of action was synthesized and tested. To understand molecular basis of this improvement, comparative conformational studies of amphotericin B and its two more selectivederivatives were carried out in an aqueous solution and in a lipid membrane. These molecular simulation studies revealed...
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Testing of low temperature behaviour of asphalt mixtures in bending creep test
PublicationThe paper presents a method of bending beam test and its importance for evaluation of asphalt mixtures behaviour at low temperatures. Two types of asphalt mixtures: asphalt concrete AC with normal paving grade bitumen and stone mastic asphalt SMA with SBS-modified bitumen were tested. Long-term oven ageing (LTOA) test was also used in the laboratory according to SHRP procedure. The Burgers model was applied and rheological parameters...
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AN ALGORITHM FOR PORTAL HYPERTENSIVE GASTROPATHY RECOGNITION ON THE ENDOSCOPIC RECORDINGS
PublicationSymptoms recognition of portal hypertensive gastropathy (PHG) can be done by analysing endoscopic recordings, but manual analysis done by physician may take a long time. This increases probability of missing some symptoms and automated methods may be applied to prevent that. In this paper a novel hybrid algorithm for recognition of early stage of portal hypertensive gastropathy is proposed. First image preprocessing is described....
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Comparison of Single and Multi-Population Evolutionary Algorithm for Path Planning in Navigation Situation
PublicationIn this paper a comparison of single and multi-population evolutionary algorithm is presented. Tested algorithms are used to determine close to optimal ship paths in collision avoidance situation. For this purpose a path planning problem is defined. A specific structure of the individual path and fitness function is presented. Principle of operation of single-population and multi-population evolutionary algorithm is described....
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Detection of vehicles stopping in restricted zones in video from surveillance cameras
PublicationAn algorithm for detection of vehicles that stop in restricted areas, e.g. excluded by traffic rules, is proposed. Classic approaches based on object tracking are inefficient in high traffic scenes because of tracking errors caused by frequent object merging and splitting. The proposed algorithm uses the background subtraction results for detection of moving objects, then pixels belonging to moving objects are tested for stability....
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Strontium-based nanosized phosphates as anticorrosive fi llers of epoxy and polyurethane coating compositions
PublicationAnticorrosive epoxy and polyurethane coatings were compounded using zinc-free nanosized phosphates of strontium (SP) or strontium and aluminum (SAP). For comparison, a nanosized calcium aluminum ammonium phosphate (CAP) and a microsized zinc phosphate (ZP) were tested. Results of salts spray and cyclic corrosion tests revealed better anticorrosive properties of the SAP-based coatings...
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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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CONSTRUCTION TECHNOLOGY OF TIMBER-FRAME HOUSES RESISTANT TO DYNAMIC LOADS – STUDY ON MODELS OF EXTERIOR WALLS
PublicationThe aim of this paper is to show the numeric representation of experimental studies concerning the behaviour of exterior wall models of a timber-frame house under harmonic loading. A single wall model according to traditional technology of timberframe house walls (filling with mineral wool) was tested. The analysis was conducted for the following frequencies: 0.5 Hz, 1.0 Hz, 2.0 Hz and 5.0 Hz for various values of the specified...
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A new diagnostic method for evaluation of cardiosurgery wound healing
PublicationOne of important and still unsolved problems in medicine is the question of objective and quantitative evaluation of post-surgery wound healing. The aim of this research is to analyse possibility and value of using the newly elaborated infrared imaging procedure – Active Dynamic Thermography (ADT) – for quantitative description of wound healing processes in cardiosurgery. Both, classical thermal figures of merit as well as ADT...
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EVALUATION OF THE SEMIVARIOGRAM SELECTION ON THE KRIGING INTERPOLATION
PublicationThe aim of the paper is to present the possibilities of geostatistical interpolation kriging method using in the process of generating digital terrain models (DTM). The source of data is a direct measurements realized with a precision GNSS positioning kinematic measurement technique RTN. Kriging algorithm was analysed, especially in the meaning of a semivariogram every step. Theoretical semivariogram selection influence on the...
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Synthesis and biological evaluation of novel analogues of batracylin with synthetic amino acids and adenosine: an unexpected effect on centromere segregation in tumor cells through a dual inhibition of topoisomerase IIa and Aurora B
PublicationIn the search for new anticancer agents we designed and synthesized batracylin derivatives with linking synthetic amino acid side chains of different lengths and adenosine. Unexpectedly, we have found that in water and the culture media adenosine–amino acid–BAT conjugates form supramolecular structures and this prevents these compounds from entering cells. Consequently, these compounds exerted no biological activity when tested...
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Effect of plasma sprayed and laser re-melted Al2O3 coatings on hardness and wear properties of stainless steel
PublicationCommercially available austenic stainless steel substrate was coated with commercially available, raw Al2O3 powder applied by means of plasma spraying method and then re-melted with CO2 laser beam of various parameters. Tribological and mechanical properties of the 120 J/mm and 160 J/mm laser re-melted coatings were compared with the tribological and mechanical properties of the “as-sprayed” coating. The influence of the laser...
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Isolation and characterization of Acid Soluble Collagen from the Skin of African Catfish (Clarias gariepinus), Salmon (Salmo salar) and Baltic cod (Gadus morhua)
PublicationAcid-soluble collagen (ASC) from the fish skin of African catfish (Clarias gariepinus), Salmon (Salmo salar) and Baltic cod (Gadus morhua) was extracted and characterized. The ASC extraction yield was 75%, 73% and 68%, respectively. The denaturation and melting temperatures of African catfish ASC (29.3°C and 100.0°C) were significantly higher than ASC of Salmon and Baltic cod (20.6°C and 90.5°C; 15.2°C and 86.7°C, respectively), assessed...
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Performance of Noise Map Service Working in Cloud Computing Environment
PublicationIn the paper a noise map service designated for the user interested in environmental noise subject is presented. It is based on cloud computing. Noise prediction algorithm and source model, developed for creating acoustic maps, are working in cloud computing environment. In the study issues related to noise modeling of sound propagation in urban spaces are discussed with a special focus on road noise. Examples of results obtained...
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Determination of dryout localization using a five-equation model of annular flow for boiling in minichannels
PublicationDetailed studies have suggested that the critical heat flux in the form of dryout in minichannels occurs when the combined effects of entrainment, deposition, and evaporation of the film make the film flow rate go gradually and smoothly to zero. Most approaches so far used the mass balance equation for the liquid film with appropriate formulations for the rate of deposition and entrainment respectively. It must be acknowledged...
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Measurements of flicker noise in supercapacitor cells
PublicationFlicker noise (1/f-like noise) is often used to assess the quality of various materials and devices. This phenomenon has been observed in different electrochemical devices or reactions (e.g., smart windows, pitting corrosion events). In our exploratory studies we consider how to measure and utilize 1/f noise for the quality assessment of supercapacitors. This task requires special attention because of enormous capacitance of the...
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Evaluation of Gas Chromatography Stationary Phases Based on Morpholinium Ionic Liquids by McReynolds Constants and Activity Coefficients at Infinite Dilution
PublicationIn this work, four ionic liquids (ILs) based on the N-alkyl-N-methylmorpholinium cation ([Mor1,R], in which R = 2, 4, 8, or 10) and bis (trifluoromethanesulfonyl)imide anion were synthesized. Using GLC, a number of parameters describing the sorption properties of the investigated ILs were determined. The values of Kovats indices, McReynolds constants, and activity coefficients at infinite dilution were the basis for the evaluation...
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Detection system for optical coherence tomography: Czerny-Turner spectrometer
PublicationResearch methods based on spectral analysis have powerful impact on development in many field of science. Signal spectrum can be a source of useful and important data. It enables to obtain information about physical and chemical properties of tested materials. This paper has been devoted to describe optical design for high resolution spectrometer, which is significant element of optical coherence tomography (OCT) systems. Designed...
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Detection of apple in orange juice using ultra-fast gas chromatography
PublicationThe determination of authenticity is an increasingly important issue for food quality and safety. The use of an electronic nose based on ultra-fast gas chromatography technique ensures rapid analysis of the volatile compounds from food products. Due to the fact that this technique enables chemical profiling of agricultural products, it can be an effective tool for authentication when combined with chemometrics. In this article...
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Alternative diagnostic method applied on marine diesel engines having limited monitoring susceptibility
PublicationThe paper presents a method of technical state evaluation of working spaces of a marine diesel engine at the limited control susceptibility. The method foresees making a diagnosis of the engine's working spaces on the basis of measurements of the exhaust gas pressure in the channels connecting engine cylinders with the turbocharger's turbine. Diagnostic measurements are carried out at representative (comparative) steady loads depending...
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Problems of analytical determination of journal bearing bush fatigue strength estimates
PublicationProblems connected with determination of stress distribution in sliding layer of thinwalled bearing bushes, investigated in bearing fatigue test rigs, have been presented. Using an example of plain bearings tested in the fatigue machine SMOK (built at the Gdask University of Technology) problems with obtaining a convergence of iterative procedure for determining the fatigue strength estimators of bearing alloy surface layer are...
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Multibeam sonar data processing for seafloor characterisation
PublicationThe approach to seafloor characterisation was investigated. It relies on calculation of several descriptors (parameters) related to seabed type using three types of multibeam sonar data obtained during seafloor sensing: 1) the grey-level sonar images of seabed, 2) the 3D model of the seabed surface which consist of (x, y, z) points, 3) the set of time domain echo envelopes corresponding to several beams. The proposed method has...
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Combined method of multibeam sonar signal processing and image analysis for seafloor classification
PublicationThe combined approach to seafloor characterisation was investigated. It relies on calculation of several descriptors (parameters) related to seabed type using three types of multibeam sonar data obtained during seafloor sensing: 1) the grey-level sonar images (echograms) of seabed, 2) the 3D model of the seabed surface which consists of bathymetric data, 3) the set of time domain bottom echo envelopes received in the consecutive...
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On degradation of glass/polyester laminate immersed in water
PublicationMechanical behaviour was compared for glass/ polyester laminates manufactured in the boatbuilding plant using three methods: hand lay-up, vacuum bagging, infusion. Specimens were tested in dry condition and following accelerated water immersion test (70°C- corresponding to the exposure of 30 years at 19°C). In three point bending test 40-50% reduction in laminate strength was observed due to water immersion. The highest degradation...
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Multibeam data processing for 3D object shape reconstruction
PublicationThe technology of hydroacoustic scanning offers an efficient and widely-used source of geospatial information regarding underwater environments, providing measurement data which usually have the structure of irregular groups of points known as point clouds. Since this data model has known disadvantages, a different form of representation based on representing surfaces with simple geometric structures, such as edges and facets,...
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Influence of the ionic strength on the amyloid fibrillogenesis of hen egg white lysozyme
PublicationThe study investigates the role of the electrostatic interactions in the fibrillation of the hen egg white lysozyme (HEWL). In order to achieve this aim the influence of the cations Na+, Mg2+ and Al3+ on the amyloid fibril formation and amorphous aggregation was tested. The amyloids are formed in the solution without added salt but the Thioflavin T fluorescence gives the false-negative result. In these conditions, the HEWL fibrils...
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Bimodal classification of English allophones employing acoustic speech signal and facial motion capture
PublicationA method for automatic transcription of English speech into International Phonetic Alphabet (IPA) system is developed and studied. The principal objective of the study is to evaluate to what extent the visual data related to lip reading can enhance recognition accuracy of the transcription of English consonantal and vocalic allophones. To this end, motion capture markers were placed on the faces of seven speakers to obtain lip...
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Experimental investigation on straight and u-bend double tube heat exchanger with active and passive enhancement methods
PublicationAuthors in this work want to demonstrate the possibility to increase the heat transfer efficiency by using simple wire coil inserts to create turbulent flow in the boundary layer as well as air blowing into the annulus of the pipe. In the study, Wilson plot approach was applied in order to estimate heat transfer coefficients for all heat exchanger (HX) configurations. The study focuses on experimental values of heat transfer coefficient...
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Nanoparticles displacement analysis using optical coherence tomography
PublicationOptical coherence tomography (OCT) is a versatile optical method for cross-sectional and 3D imaging of biological and non-biological objects. Here we are going to present the application of polarization sensitive spectroscopic OCT system (PS-SOCT) for quantitative measurements of materials containing nanoparticles. The PS-SOCT combines the polarization sensitive analysis with time-frequency analysis. In this contribution the benefits...
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Hardware cryptography coprocessor for system on chip soft processor
PublicationW artykule przedstawiono realizację sprzętową i programową szyfrującejo i deszyfrującego algorytmu AES.Obydwie implementacje zostały zralizowane z wykorzystaniem układu Virtex II i przetestowane. Jako kryterium porónawcze wybrano zużycie zasobów układu oraz wydajność. Realizacja sprzętowa wykonuje operację szyfrowania 2 dekady szybcie niż wersja programowa, ale wymaga pięciokrotnie więcej zasobówIn this paper hardware and software...
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The influence of the motor filtrers on harmonic current emmision in the pro-ective connection of drive systems.
PublicationThis paper contains detailed analysis of currents in protective wire in engine supplied from frequency converter without any external filters added. It was found that the peak value of current in protective conductor of engine was about 1500 mA at frequencies 5 Hz 50 Hz. In the continuation of research the dU/dt type motor filter and the sinusoidal filter were tested. It was found that the current in protective wire decreased...
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Emotions and Their Relation with Knowledge Risks in Organizations
PublicationThe aim of this chapter is to analyze and present knowledge risks from the perspective of emotions. Every year, new studies are published, where novel aspects of knowledge management field are examined and tested. One of such aspects that is worth examination and exploration is the role of emotions (both positive and negative) experienced by employees and managers that can contribute to their behaviors concerning knowledge risks...
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High Efficiency Dual-Active-Bridge Converter with Triple-Phase-Shift Control for Battery Charger of Electric Vehicles
PublicationAn optimal modulation scheme with triple-phase-shift (TPS) control could increase the efficiency in the entire load range for a dual-active-bridge (DAB) converter under wide output voltage range conditions. Therefore, this study proposes a convergent approach to TPS mode selection, coupled with an optimal modulation scheme, ensuring the circuit’s efficiency over the entire range in the realm of a high-power and high-efficiency...
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Numerical Determination of the Load-Bearing Capacity of a Perforated Thin-Walled Beam in a Structural System with a Steel Grating
PublicationThis article presents the results of numerical simulations of a structural system consisting of steel perforated thin-walled beams and a steel grating. The simulations were conducted using the finite element method. The analysis took into account physical and geometric nonlinearity as well as the contact between the steel grating and the beams. The main goal of the research was to develop load-bearing curves for the main beam in...
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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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Quasistatic and fatigue behavior of an AISI H13 steel obtained by additive manufacturing and conventional method
PublicationThis work aims to compare the mechanical behavior of an AISI H13 steel obtained by additive manufacturing with that obtained by conventional manufacturing methods. The average values of the ultimate tensile strength (UTS) and ductility obtained for the specimens produced by the conventional method were equal to 658 MPa and 18%, respectively, which compares with 503 MPa and 0.75% registered for the selective laser melting (SLM)...
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Effect of convection and microwave heating on the retention of bioactive components in human milk
PublicationBioactive substances are very important components of human milk (HM), especially for premature newborns. The effects of convection (CH) and microwave heating (MWH) at 62.5 and 66 °C, on the level of selected bioactive components of HM: lysozyme (LZ), lactoferrin (LF), secretory immunoglobulin A (sIgA), basal lipase (BL), cytokine TGF-2, vitamin C and total antioxidant capacity (TAC) was compared. Regardless of the used heating methods...
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A model of the response of the MGS-6 gravity sensor to tilting
PublicationThe reliable interpretation of the measurements made by the Micro-g marine gravimetric system (MGS-6) depends on how the temporary changes of the scale coefficients such as gravimeter scale factor, vertical cross-coupling (VCC) effect, tiltmeter cross and tiltmeter long are compensated for during the signal analysis. The listed coefficients cannot be determined from readings during the measurements or by analysing the final data....
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Synthesis of a state feedback controller for an averaging tank with variable filling
PublicationIn paper, a nonlinear averaging tank with variable filling is considered. The main purpose of this research work was the modelling and control system synthesis of an averaging tank. The control objectives included ensuring stability and zero steady-state error of the system and achieving settling time as short as possible, while maintaining a minimal overshoot. In order to achieve the intended purpose, firstly a mathematical model...