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Thin-walled cross section shape influence on steel member resistance.
PublikacjaThis work describes why trending thin-walled technology is achieving popularity in steel construction sector. A purpose of this article is to present the influence of the cold-formed element cross-section shape on an axial compression and a bending moment resistance. The authors have considered four different shapes assuming constant section area and thickness. Calculations were based on three different steel grades taking into...
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IoT for healthcare applications
PublikacjaThis chapter summarizes IRACON contributions related to the application of IoT in healthcare. It consists of the following three sections. Section 8.1 presents the measurement campaigns and the related statistical analysis to obtain various channel models for wearable and implantable devices. In addition, the importance of physical human-body phantoms used for channel, Specific Absorption Rate (SAR), and Electromagnetic (EM) exposure...
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An Analysis of Cylindrical Posts of Arbitrary Convex Cross Sections Located in Waveguide Junctions with the Use of Field Matching Method
PublikacjaA problem of electromagnetic wave scattering from cylindrical posts of arbitrary cross section located in waveguide junction is presented. The method of analysis is based on the direct field matching technique. Multimode scattering matrices of every section of waveguide junction are calculated and cascading procedure is utilized to investigate the whole structure. The results are verified by comparing them with those obtained from...
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Cognitum Ontorion: Knowledge Representation and Reasoning System
PublikacjaAt any point of human activity, knowledge and expertise are a key factors in understanding and solving any given problem. In present days, computer systems have the ability to support their users in an efficient and reliable way in gathering and processing knowledge. In this chapter we show how to use Cognitum Ontorion system in this areas. In first section, we identify emerging issues focused on how to represent and inference...
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Impact of maintenance of floodplains of the Vistula River on high water levels on the section from Włocławek to Toruń
PublikacjaThis article describes the methodology of hydraulic calculations to estimate the water levels in open channels for steady gradually varied flow. The presented method has been used to analyse the water level on the Vistula River from Włocławek cross-section to Toruń cross-section. The HEC-RAS modelling system has been used for parameterization of the river channel and floodplains, as well as for flow simulation. The results obtained...
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Innovative Cold-formed GEB Section under Bending
PublikacjaThis paper is concerned with the numerical bending capacity study of the innovative cold-formed GEB sections. Both linear buckling analysis and non-linear static analysis incorporating geometric and material nonlinearity were carried out employing a shell structural model. The magnitudes of buckling load and limit load with respect to GEB section depth and thickness were obtained. The opened cold-formed section was tested assuming...
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Innovative cold-formed GEB section under compression
PublikacjaCold-formed steel sections extensively affect the modern steel construction industry. Not only are they used as secondary elements like purlins or sheeting, but also they can serve as primary load-bearing members in fabricated steel panels and trusses. A new cross-section called shortly a GEB may serve as that member. However, its existence of the metal building structures industry depends on the exact, optimal dimensional parameters...
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Cross section calculations for electron scattering from platinum chemotherapeutic compounds
PublikacjaCross section for electron impact ionization of carboplatin, C6H12N2O4Pt, and oxaliplatin, C8H14N2O4Pt, have been calculated within binary-encounter-Bethe model for energies from the ionization threshold up to 5000 eV. Cross section for elastic electron scattering from carboplatin and oxaliplatin molecules have also been derived using independent atom method (IAM) and additivity rule for collision energies ranging from 50 eV to...
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Influence of stirrups in a concrete shell on strengthening reinforced concrete column
PublikacjaTwelve concrete columns, with a 150x150mm square section and three columns with a circular section (d=200mm), are tested to investigate the effect of strengthening by RC jacket. Based on a confined concrete model for axial static loading, an analytical methods, reported in the literature are proposed to predict the behavior of columns with RC jacket. The results support the conception that the effect of strengthening depends...
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Air flow phenomena in the model of the blind drift
PublikacjaIn the presented paper, Particle Image Velocimetry (PIV) has been used to investigate flow pattern and turbulent structure in the model of blind drift. The presented model exist in mining, and has been analyzed to resolve ventilation issues. Blind region is particularly susceptible to unsafe methane accumulation. The measurement system allows us to evaluate all components of the velocity vector in channel cross-section simultaneously....
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Multilevel Converters
PublikacjaThe newest Special Section is intended to focus on recent research and trends in application of multilevel converters. Multilevel converters have been extensively developed over the last two decades and show several important advantages of power electronic circuits, such as: operation at high voltages, harmonics reduction, higher efficiency, modularity, smaller size and lower cost. Also, thanks to increasing interest in renewable...
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A quasi-2D small-signal MOSFET model - main results
PublikacjaDynamic properties of the MOS transistor under small-signal excitation are determined by kinetic parameters of the carriers injected into the channel, i.e., the low-field mobility, velocity saturation, mobility at the quiescent-point (Q-point), longitudinal electric field in the channel, by dynamic properties of the channel, as well as by an electrical coupling between the perturbed carrier concentration in the channel and the...
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DEFORMATIONS OF INNOVATIVE COLD-FORMED GEB SECTIONS
PublikacjaPermanent urban growth of the world of today world implies demanding challenges for the steel construction industry. Nowadays, one of the most important issues is the cost optimization of steel structures. Since the weight of building materials is a major component of the total cost, engineers and designers try to reduce structural weight, without compromising durability and sustainability of a steel structure. Therefore, light...
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L’indistricabile intreccio. Imprese, imprenditori e regime fascista. (An Inextricable Intertwining. Companies, Entrepreneurs, and the Fascist Regime)
PublikacjaThe papers of this section analyse the relationships between the economic and business community and the fascist regime. Their aim is to refresh the interpretations that were established in the 1960s-1970s and remained undisputed in the decades thereafter, becoming a sort of mantra among Italian contemporary historians. The article presents the most relevant contributions of that historiographical season, explaining the reasons...
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Influence of nodes with positive eccentricity on load-carrying capasity of truss' top chords in trusses made of welded cold-formed members.
PublikacjaIn order to establish the influence of eccentric crossing of truss members on the load-carrying capacity of the folded chord of a hat-section truss, a research model was created and preliminary numerical analysis of the truss was performed with the use of Marc Mentat programme. Distorial instability of crossheads caused by deviation of loose (unmounted) channel section web’s bends was observed. Due to the slenderness of the section’s...
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Measuring and Analyzing Audio Levels in Film, Commercials, and Movie Trailers Using Leq(A) Values and the LUFS Loudness Model . Analiza pomiarów dźwięku w filmie oraz w reklamach filmowych z wykorzystaniem modelu głośności
PublikacjaThe purpose of this paper is to describe the measurement of loudness levels in movies, movie trailers, and commercials displayed before feature films at movie theaters. In the initial section, the paper discusses the issues related to measurement of loudness levels, provides recommendations regarding permissible loudness levels during movie screenings, and mentions the applied units of measurement. The following section of the...
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Updating Finite Element Model of a Wind Turbine Blade Section Using Experimental Modal Analysis Results
PublikacjaThis paper presents selected results and aspects of themultidisciplinary and interdisciplinary research oriented for the experimental and numerical study of the structural dynamics of a bend-twist coupled full scale section of awind turbine blade structure.Themain goal of the conducted research is to validate finite elementmodel of themodified wind turbine blade section mounted in the flexible support structure accordingly to the...
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STABILITY AND LOAD BEARING CAPACITY OF A BARS WITH BUILT UP CROSS SECTION AND ELASTIC SUPPORTS
PublikacjaThe present paper is devoted to the numerical analysis and experimental tests of compressed bars with built–up cross section which are commonly used as a top chord of the roof trusses. The significant impact on carrying capacity for that kind of elements in case of out-of-plane buckling is appropriate choice of battens which are used to provide interaction between separate members. Linear buckling analysis results and nonlinear static...
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Refined theoretical study of radiative association: Cross sections and rate constants for the formation of SiN
PublikacjaRadiative association of silicon mononitride (SiN) in its two lowest molecular electronic states is studied through quantum and classical dynamics. Special attention is paid to the behavior of the cross section at high collision energies. A modified expression for the semiclassical cross section is presented which excludes transitions to continuum states. This gives improved agreement with quantum mechanical perturbation theory...
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A compact seven-section rat-race hybrid coupler incorporating pbg cells
PublikacjaA conventional rat-race coupler has been doubly miniaturized: (i) characteristic impedances and electrical lengths of microstrip sections have been adequately modified as the first step of size reduction and (ii) T-shaped PBG cells have been implemented to diminish strip section length as the second step of circuit rat-race couplerminiaturization. The experimental results show good agreement with theoretical characteristics. Furthermore,...
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Investigations on mixture preparation for two phase adiabatic pressure drop of R134a flowing in 5 mm diameter channel
PublikacjaThe article presents detailed two-phase adiabatic pressure drops data for refrigerant R134a. Study cases have been set for a mass flux varying from 200 to 400 kg/m2 s, at the saturation temperature of 19.4 ◦C. Obtained experimental data was compared with the available correlations from the literature for the frictional pressure drop during adiabatic flow. Influence of mixture preparation on pressure drop was investigated, for...
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Normal stress distribution in built‑up cold‑formed column in relation to interconnecting bolt spacing
PublikacjaIn order to increase a stiffness of cold-formed steel (CFS) elements it is practised to built-up the cross-section. In the analysed case, a main element is strengthened by adding extra chord in contact partially along the column. This additional chord acts as a longitudinal stiffener connected with the main section by series of bolts. Authors check whether rules applied over the years, for hot-rolled elements, can be indiscriminately...
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Modeling of the Two-Dimensional Flow Caused by Sea Conditions and Wind Stresses on the Example of Dead Vistula
PublikacjaThe article presents the results of two-dimensional modeling of flows caused by the sea conditions and wind stresses on the example of Dead Vistula. Based on the available bathymetric data, a numerical model of the river section was created, which was supplemented with data on the position of the water table depending on hydrometeorological conditions. To describe the flow field in steady conditions, a simplified model of two-dimensional...
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Electron Scattering from Methyl Formate (HCOOCH3): A Joint Theoretical and Experimental Study
PublikacjaElastic low-energy electron collisions with methyl formate have been studied theoretically at the level of various theories. The elastic integral cross section was calculated using Schwinger multichannel and R-matrix methods, in the static-exchange and static-exchange plus polarization levels of approximations for energies up to 15 eV. The absolute total cross section for electron scattering from methyl formate has been measured...
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Assessment of Wooden Beams from Historical Buildings Using Ultrasonic Transmission Tomography
PublikacjaThe main goal of this study was non-destructive evaluation of wooden elements using ultrasonic waves. The inspection was carried out on wooden beams from a historical object. Elastic wave signals were processed by ultrasonic transmission tomography to obtain imaging of the internal structure of tested elements without disturbing their state and integrity. The focus was on the influence of wood anisotropy on the propagation of ultrasonic...
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Sensitivity analysis of a composite footbridge
PublikacjaThis work include an example of sensitivity analysis for the design of a composite footbridge. A sandwich structure is used, consisting two high-strength skins separated by a core material. The analysis was conducted for two numerical models. The first one is a simple, single-span beam of a composite cross-section (laminate and foam), with different Young’s modulus for each material. Calculations were made by means of a MATLAB-based...
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Sustainability, reliability, and durability of civil engineering structures
PublikacjaConsidering the Bulletin Readers’ interest in civil engineering,the Special Section “Sustainability, reliability, and durability of civil engineering structures” is now presented, with papers that, by studying specific cases, fully embrace all aspects related to the topic, starting from geometry design, determination of load acting on a structure, characteristics of the material for construction purpose, characteristics of structural...
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LOCAL E-MARKETING AND PHARAMACY SELECTION PROCESS AMONG CURRENT AND PROSPECTIVE CONSUMERS
PublikacjaWORK OBJECTIVES: To examine whether and to what extent a company's presence in Google Search mobile results, and Google Maps service search results, affects pharmacies' acquisition of new consumers RESEARCH QUESTIONS: Does the presence of pharmacies in Google MyBusiness increase the number of their customers ? Is the increase in the...
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The effect of paleo-environment on hydrocarbon generation potential: Example from Vaca Muerta Formation, Neuquén Basin, Argentina
PublikacjaA 137-m continuous core from the Jurassic-Early Cretaceous marine derived oil shale with the maturity Ro about 0.7 %, representing the oil window in the Vaca Muerta Formation, Neuquén Basin, Argentina, was examined using geological, mineralogical, petrographic, and geochemistry techniques. Three distinct intervals were identified within the core: the upper carbonate-rich section with intense bioturbation, indicating dysoxic to...
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Diagnosing marine turbine engines through energy characteristics of their flow section
PublikacjaThe aim of the performed research was to develop of diagnostic method of the flow section of a marine turbine combustion engine based on the level of delamination of its energy characteristics. The here adopted diagnostic model provides for a formulation of the evaluation of the technical conditions based on the measurements of the parameters of the thermodynamic medium in the characteristic control cross-sections of the engine...
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Experimental tests and numerical simulations of full scale composite sandwich segment of a foot- and cycle- bridge
PublikacjaIn the paper experimental tests and numerical simulations of a full cross-section segment of ultimately designed foot-and cycle-bridge are presented. The experimental tests were conducted on element with length reduced to 3 m and unchanged (target) cross-section dimensions. The external skin of structure is GFRP laminate while internal core is PET foam. Several quasi-static tests were performed using hydraulic cylinder to generate...
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Electron impact ionization and cationic fragmentation of the pyridazine molecules
PublikacjaElectron impact mass spectroscopy was used to investigate ionization and cationic fragmentation of the pyridazine (1,2 diazine), C4H4N2, molecules in the gas phase. The mass spectra were measured and the observed mass peaks assigned to the corresponding cations. The appearance energies of most of the cationic fragments were determined and the possible fragmentation processes are discussed. The total cross section for electron...
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Experimental Investigation of the Thermal Performance of a Wickless Heat Pipe Operating with Different Fluids: Water, Ethanol, and SES36. Analysis of Influences of Instability Processes at Working Operation Parameters
PublikacjaIn this study, the influences of different parameters on performance of a wickless heat pipe have been presented. Experiments have been carried out for an input power range from 50 W to 300 W, constant cooling water mass flow rate of 0.01 kg/s, and constant temperature at the inlet to condenser of 10 C. Three working fluids have been tested: water, ethanol, and SES36 (1,1,1,3,3-Pentafluorobutane) with different filling ratios (0.32,...
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Enhanced method of DS-CDMA low level singnals detection
PublikacjaThe following article comprises three main parts. The first one generally describes two methods of low level signals detection which are in the interest of this study. The signal spectrum averaging technique is shown as well as the method exploiting averaged spectrum of the signal raised to the power of 2n (nN). Additionally, this section briefly presents proposed enhancements and modifications of these two solutions, which allow...
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Shell model of multiple-row moment I-section end-plate joint
PublikacjaThe paper deals with a problem of application of shell elements in the models of multiple-row moment end-plate connections. The extended connection of I-section with a cross-section W760x265x220 made of steel S355 was analyzed. Comparison analysis of FEM, complex volume and shell models has been done. Three cases with different end-plate thickness: 14, 18 and 36 mm were analyzed and compared with the reference results. Comparison...
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Methylation effect in e−— scattering on methyl-substituted ethylenes
PublikacjaMethylation effect has been observed and studied in electron-scattering from selected hydrocarbon molecules. In measured total cross section (TCS) functions we have noticed energy shifts and changes in the intensity of observed structures.
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Electron-impact ionization cross section of formic acid
PublikacjaExperimental electron-impact ionization cross sections of one of the simplest carboxylic acids, formic acid, are presented. The molecular target was studied in two independent experimental setups applying different methods: the total ion collection and the electron–impact mass spectrometry methods. Experimental data were taken at incident electron energies ranging from ionization threshold [11.31 eV; J.C. Traeger, Int. J. Mass...
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Joint experimental and theoretical study on electron scattering from titanium tetrachloride (TiCl4) molecule
PublikacjaAbsolute grand-total cross section for electron scattering from titanium tetrachloride, TiCl4, molecule was measured at electron-impact energies ranging from 0.3 to 300 eV, in the linear electron-transmission experiment. The elastic integral, differential, momentum transfer, and total ionization cross sections for TiCl4 molecule were also calculated for low and intermediate collisional energies at the level of various theories. The...
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TB11 test for short w-beam road barrier
PublikacjaFEM (Finite Element Method) is well-suited and widely used tool for simulating a range of phenomena: from these with simple and static behaviour, up to those complicated, highly nonlinear and involving many contacts. In present paper we use one of the advantages of FEM: parametric study could be easily performed and is more economical than series of in-situ tests. If recommended practices is carefully followed, results obtained...
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Retrospecting Polish Audio Engineering Society Membership on 20th Anniversary of the Polish Section of the Audio Engineering Society
PublikacjaIn this article some key events concerning founding Polish Section of the Audio Engineering Society were presented. In addition, the history covering International Symposia on Sound Engineering and Mastering was outlined. Also, papers contained in this issue were shortly reviewed.
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Vibro-Electrical Behavior of a Viscoelastic Piezo-Nanowire in an Elastic Substrate Considering Stress Nonlocality and Microstructural Size-Dependent Effects
PublikacjaThis research deals with dynamics response of a Pol/BaTiO3 nanowire including viscosity influences. The wire is also impressed by a longitudinal electric field. Hamilton's principle and Lagrangian strains are employed in conjunction with a refined higher-order beam theory in order to derive equations of motion. By combining nonlocality and small size...
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Novel method of lung area extraction in chest perfusion computed tomography
PublikacjaChest perfusion computed tomography (pCT) is a useful technique in the medical diagnosis of how organs function. Perfusion CT scans are used to calculate perfusion parameters. In the case of automated methods of lung perfusion parameters calculation, the prior extraction of the lung area is desired to avoid unnecessary calculation in an area outside the lung cross-section and to avoid wasting time on processing signals of no diagnostic...
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Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines. Part I: Steady-state processes
PublikacjaThe article presents a possible method of detecting failures in the flow section and supply system of a naval gas turbine engine based on the exhaust gas temperature measured behind the gas generator. This temperature is a basic diagnostic parameter use for evaluating the technical state of the turbine engine in operation, and is monitored during engine start-ups, accelerations and decelerations of rotor units, and steady-load...
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The selected hydrotechnical conditions of the Dnieper – Bug Channel and the Pripyat River in the development of the International Waterway E40
PublikacjaInternational waterway E40 (MDW E40) is included in the network of inland waterways of transnational importance. It is a link between two areas: the Baltic Sea and the Black Sea. E40 route runs through three countries: Poland, Belarus and Ukraine. The article presents the results of the study on the analysis of two very important sections of the MDW E40 on the Belarusian section, it is:. the Dnieper – Bug Channel and the Pripy...
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Cross-Section Calculations for Electron-Impact Ionization of Pyrimidine Molecule and Its Halogenated Derivatives: 2-Chloropyrimidine, 5-Chloropyrimidine, 2-Bromopyrimidine and 5-Bromopyrimidine
PublikacjaThe total cross-sections for the single electron-impact ionization of pyrimidine (C4H4N2), 2-chloropyrimidine (2-C4H3ClN2), 5-chloropyrimidine (5-C4H3ClN2), 2-bromopyrimidine (2-C4H3BrN2) and 5-bromopyrimidine (5-C4H3BrN2) molecules have been calculated with the binary-encounter-Bethe model from the ionization threshold up to 5 keV. The input data for the BEB calculations concerning electronic structure of the studied targets have...
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A novel section–section potential for short-range interactions between plane beams
PublikacjaWe derive a novel formulation for the interaction potential between deformable fibers due to short-range fields arising from intermolecular forces. The formulation improves the existing section–section interaction potential law for in-plane beams by considering an offset between interacting cross sections. The new law is asymptotically consistent, which is particularly beneficial for computationally demanding scenarios involving...
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On the generalized model of shell structures with functional cross-sections
PublikacjaIn the present study, a single general formulation has been presented for the analysis of various shell-shaped structures. The proposed model is comprehensive and a variety of theories can be used based on it. The cross-section of the shell structure can be arbitrarily analyzed with the presented equations. In other words, various types of shell structures, including cylindrical, conical, spherical, elliptical, hyperbolic, parabolic,...
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Novel strategies to enhance hydrodynamic cavitation in a circular venturi using RANS numerical simulations
PublikacjaHydrodynamic cavitation is a popular advanced oxidation technique and it has received wide range of applications from waste water treatment to the nanoparticles synthesis in recent years. The enhancement of the intensity of the hydrodynamic cavitation is always been an emerging field of research. Within this framework, we have proposed and investigated three distinct strategies to enhance the intensity of cavitation in a circular...
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Laboratory Load Model Based on 150 kVA Power Frequency Converter and Simulink Real-Time – Concept, mplementation, Experiments
PublikacjaFirst section of the paper provides technical specification of laboratory load model basing on 150 kVA power frequency converter and Simulink Real-Time platform. Assumptions, as well as control algorithm structure is presented. Theoretical considerations based on criteria which load types may be simulated using discussed laboratory setup, are described. As described model contains transformer with thyristor-controlled tap changer,...
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Thermodynamic and economic analysis of nuclear power unit operating in partial cogeneration mode to produce electricity and district heat
PublikacjaThis paper presents the methodology of techno-economic analysis for a nuclear unit operating in partial cogeneration mode and its application for the case study: a nuclear power plant planned in Poland. The research objectives were: to propose EPR, AP1000 and ESBWR nuclear condensing-extraction turbine systems modifications required for operation in cogeneration, to determine optimal heat production and heat transport line (HTL)...