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Search results for: BIFURKACJE RADIALNE
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Wpływ promieniowania mikrofalowego na zawartość mikroorganizmów wskaźnikowych w osadach ściekowych.
PublicationW pracy przedstawiono wpływ promieniowania mikrofalowego na właściwości sanitarne komunalnych osadów ściekowych z oczyszczalni ścieków ''Wschód'' w Gdańsku, tj. na zawartość pasożytów Ascaris sp., Trichuris sp. i Toxocara sp. oraz wybranych bakterii wskaźnikowych. Promieniowanie mikrofalowe powodowało radykalne zmniejszenie zawartości mikroorganizmów chorobotwórczych w osadach ściekowych, a zarazem powodowało wzrost ich podatności...
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Solution of coupled integral equations for quantum scattering in the presence of complex potentials
PublicationIn this paper, we present a method to compute solutions of coupled integral equations for quantum scattering problems in the presence of a complex potential. We show how the elastic and absorption cross sections can be obtained from the numerical solution of these equations in the asymptotic region at large radial distances.
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Structure of liquid gold from tight-binding driven molecular-dynamics
PublicationPraca przedstawia wyniki symulacji ciekłego złota w nadkomórce periodycznej przy użyciu stworzonego przez autorów programu komputerowego, za pomocą połączonych metod dynamiki molekularnej (MD) i ciasnego wiązania (TB). Omówiono strukturę tak symulowanej cieczy, porównując ją z dostępnymi danymi doświadczalnymi oraz wynikami innych symulacji, pod kątem radialnej i kątowej funkcji rozkładu i elektronowej gęstości stanów.A tight-binding...
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Zmiana jako kondycja współczesnego życia społecznego na przykładzie identyfikacji i satysfakcji zawodowej polskich nauczycieli
PublicationW tekście zaprezentowano wyniki badań ankietowych o deskryptywnym charakterze, odnoszących się do wybranych wymiarów tożsamości zawodowej nauczycieli, takich jak między innymi kwestia identyfikacji z zawodem, poczucia dumy z powodu jego wykonywania, poczucia satysfakcji zawodowej i ogólnożyciowej oraz motywacji wyboru drogi życiowej i zawodowej. Kontekstem dla badań są dynamiczne i radykalne zmiany charakterze społecznym, politycznym,...
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Innowacyjność firm z sektora wiedzochłonnych usług biznesowych.
PublicationArtykuł przedstawia zagadnienia związane z innowacjami w firmach oferujących wiedzochłonne usługi biznesowe (KIBS – knowledge intensive business services). Sektor biznesowych usług wiedzochłonnych ma rosnące znaczenie nie tylko z punktu widzenia firm, którym dostarcza swoje usługi, przyczyniając się do wzrostu ich konkurencyjności, ale również jako źródło innowacji. W artykule sformułowanie dwie hipotezy badawcze: H1. Firmy z...
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EFFECT OF PRESS DRYING ON DIMENSION STABILITY AND DENSITY OF BEECH WOOD,
PublicationTimber is traditionally dried in kilns by processes that often take several days or weeks to complete. At present, it is possible to apply several methods of rapid drying of timber, including, for example, press drying. This research is based on the use of this process. Drying was performed using the heating plates with a temperature of 160 °C. Three pressures were compared in the research 1.0 MPa, 1.4 MPa, and 1.8 MPa. The density...
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Aromatic heptaene antibiotics as an alternative for synthetic triazole fungicides in plant protection
PublicationAn in vitro antifungal activity of candicidin and ascosin antibiotics (0,01-10 μg/mL) towards representative strains of phytopathogenic fungi was detd. Both compds. exhibited similar half max. effective concns. inhibiting growth of the fungi as that of tebuconazole used for comparison.
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Właściwości otoczki hydratacyjnej wokół β-warstw o zróżnicowanym składzie aminokwasowym - analiza wyników dynamiki molekularnej
Publicationβ-warstwa to jedna z najczęściej spotykanych struktur drugorzędowych w białkach. Jak dotąd mechanizmy rządzące ustrukturyzowaniem wody w warstwie solwatacyjnej wokół tej struktury są słabo poznane [1]. W celu lepszego zrozumienia zjawiska hydratacji wokół struktur o konformacji β-warstwy przeprowadzono analizę wyników pochodzących z symulacji metodą dynamiki molekularnej β-warstw składających się z 8 równoległych nici o różnym...
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Measurement of distance, velocity and angle of arrival using FMCW-CW combined waveform
PublicationA procedure of tacking small flying object based on a general principle of FMCW and Doppler radar is presented. In order to increase measurement range, this technique uses active signal source on the moving object. For simultaneous measurements of distance, radial velocity and direction (AoA) as well as simplified synchronization a combined FMCW-CW waveform is proposed. The presented measurement system was realized and verified...
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New kinematic systems in single-sided lapping and their influence on lap wear
PublicationPrevious studies on one-sided lapping allow to state that not only parameters of lapping elements (i.e. properties of workpiece, abrasive grains and lapping plate) impact on a lapping efficiency. Influential are also kinematics and dynamics of the process. It is crucial to control an average velocity of lapping (v), a distribution of tangential acceleration (at), a nominal pressure (p), a lapping time (t) and disposal of workpiece...
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Anion–water interactions of weakly hydrated anions: molecular dynamics simulations of aqueous NaBF4 and NaPF6
PublicationIn aqueous ionic solutions, both the structure and the dynamics of water are altered dramatically with respect to the pure solvent. The emergence of novel experimental techniques makes these changes accessible to detailed investigations. At the same time, computational studies deliver unique possibilities for the interpretation of the experimental data at the molecular level. Here, using molecular dynamics simulations, we demonstrate...
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INVESTIGATION OF THE CHARACTERISTICS OF A LOWEMISSION GAS TURBINE COMBUSTION CHAMBER OPERATING ON A MIXTURE OF NATURAL GAS AND HYDROGEN
PublicationT his article is devoted to the investigation of the characteristics of a low-emission gas turbine combustion chamber, which can be used in Floating Production, Storage and Offloading (FPSO) vessels and operates on a mixture of natural gas and hydrogen. A new approach is proposed for modelling the processes of burning out a mixture of natural gas with hydrogen under preliminary mixing conditions in gaseous fuel with an oxidizer...
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Procesy integracji nowoczesnych systemów obrazowania ze strukturalnymi rozwiązaniami fasad budynków
PublicationObecnie, coraz częściej do nowych technologii budowlanych wkraczają te uznawane tradycyjnie za przynależące do innych dziedzin, jak technologie interaktywne, medialne czy filtrów optycznych. Ich zastosowanie zmienia sposoby architektonicznych rozwiązań fasad budynków, które projektowane są jako aktywne powierzchnie reagujące na ruch użytkowników lub zmiany parametrów bezpośredniego otoczenia. Osprzęt i systemy technologiczne są...
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On Von Karman Equations and the Buckling of a Thin Circular Elastic Plate
PublicationWe shall be concerned with the buckling of a thin circular elastic plate simply supported along a boundary, subjected to a radial compressive load uniformly distributed along its boundary. One of the main engineering concerns is to reduce deformations of plate structures. It is well known that von Karman equations provide an established model that describes nonlinear deformations of elastic plates. Our approach to study plate deformations...
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Wpływ kierowcy na opór toczenia samochodu
PublicationW pracy omówiono wpływ zachowań kierowcy na opory toczenia pojazdu w ruchu drogowym. Można tu wyróżnić styl jazdy kierowcy oraz jego dbałość o pojazd. Przedstawiono wzrost oporu toczenia w aspekcie dynamicznego przyspieszania oraz szybkiej jazdy na zakręcie. Przeanalizowano także wpływ na opór toczenia takich czynników jak: ciśnienie w ogumieniu obciążenie promieniowe, zbieżność kół jezdnych samochodu oraz zużycie ogumienia.
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Adaptive CAD-Model Construction Schemes
PublicationTwo advanced surrogate model construction techniques are discussed in this paper. The models employ radial basis function (RBF)interpolation scheme or artificial neural networks (ANN) with a new training algorithm. Adaptive sampling technique is applied withrespect to all variables. Histograms showing the quality of the models are presented. While the quality of RBF models is satisfactory, theperformance of the ANN models obtained...
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Subcritical bifurcation of free elastic shell of biological cluster
PublicationIn this paper we will investigate symmetry-breaking bifurcation of equilibrium forms of biological cluster. A biological cluster is a two-dimensional analogue of a gas balloon. The cluster boundary is connected with its kernel by elastic links. The inside part is filled with compressed gas or fluid. Equilibrium forms of biological cluster can be found as solutions of a certain second order ordinary functional-differential equation...
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Właściwości otoczki hydratacyjnej wokół różnych konformacji poliseryny - analiza wyników dynamiki molekularnej
PublicationRozpuszczalnik w istotny sposób wpływa na preferencje peptydu do przyjmowania określonej struktury drugorzędowej. Przykładem tego może być fakt, iż w przypadku polialaniny stabilność konformacji helikalnej w wodzie jest niższa aniżeli w próżni, podczas gdy w przypadku poliseryny mamy do czynienia ze zjawiskiem odwrotnym. W celu lepszego zrozumienia tego zjawiska badano właściwości otoczek hydratacyjnych dookoła czterech konformacji...
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On the broadband behaviour of planar elliptical dipole-modal approach
PublicationBroadband behavior of planar elliptical dipole structure is analyzed using Illuminatin Modes (IM) approach. The current on patch has been expanded in series of eigenfunctions in form of Mathieu radial and angular functions. The frequency behavior of current distributions and related powers have been discussed to explain the mechanism of broadband operation of the dipole. Different behavior of radiations patterns in wide frequency...
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Symmetry-Breaking Bifurcation for Free Elastic Shell of Biological Cluster, Part 2
PublicationWe will be concerned with a two-dimensional mathematical model for a free elastic shell of biological cluster. The cluster boundary is connected with its kernel by elastic links. The inside part is filled with compressed gas or fluid. Equilibrium forms of the shell of biological cluster may be found as solutions of a certain nonlinear functional-differential equation with several physical parameters. For each multiparameter this...
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WAYS TO IMPROVE THE EFFICIENCY OF WASTEWATER TREATMENT OF A CARDBOARD AND PAPER MILL
PublicationThe results of research on physical and chemical methods for the preliminary treatment of wastewater of a cardboard and paper factory in Khmelnytskyi region of Ukraine are presented. At the cardboard and paper factory, wastewater is treated at a sewage treatment plant, which includes sand traps, primary radial sedimentation tanks, aeration tanks with activated sludge regenerators, secondary radial sedimentation tanks, and bioponds....
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Pomiar efektywności i (nie-)skuteczności pośredniej studiów w polskim publicznym szkolnictwie wyższym
PublicationW artykule oszacowano efektywności studiów w 52 polskich szkołach wyższych w latach 2014-2015 za pomocą modelu hybrydowego (łączącego podejście radialne i nieradialne) z niepożądanymi efektami należącego do nieparametrycznej metody DEA. Dokonano również oceny skuteczności studiów w latach 2012-2015. Wyniki badania efektywności i nieskuteczności studiów przedstawiono dla poszczególnych 52 uczelni oraz pięciu grup szkolnictwa...
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Modal Analysis of Planar Elliptical Resonator Deposited on Unshielded Dielectric Slab
PublicationModal analysis of isolated open planar elliptical patch placed on dielectric slab is presented in the paper. It applies concept of Illuminating Modes which is formulated for the case of two-side opened structure. The current on patch is expanded in basis functions in form of Mathieu radial and angular functions. The spectrum of excited modes for exemplary planar resonators is presented and discussed using the concept of power of...
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A LUMPED-CIRCUIT MODEL OF CIRCULAR PISTON TRANSDUCER FOR MODELING ITS PERFORMANCE IN DUAL FREQUENCY OPERATING MODES
PublicationThe paper presents novel network equivalent circuit of piezoceramic circular disc transducer that takes into account thickness and ra dial mode of vibrations. The starting point of the analysis is 4-port description of circular disc element representing the solution of wave equation set in radial and thickness directions. Th e approximate solution for harmonic case is represented in the form of 4x4 matrix, which is syn thesized...
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Two-dimensional hydrogen-like atom in a weak magnetic field
PublicationWe consider a non-relativistic two-dimensional (2D) hydrogen-like atom in a weak, static, uniform magnetic field perpendicular to the atomic plane. Within the framework of the Rayleigh-Schr¨odinger perturbation theory, using the Sturmian expansion of the generalized radial Coulomb Green function, we derive explicit analytical expressions for corrections to an arbitrary planar hydrogenic bound-state energy level, up to the fourth...
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Elliptical slot UWB monopole antenna
PublicationThe UWB monopole antenna with elliptical radiating slot end and microstrip feeding line terminated with radial stub have been designed, fabricated and measured. The antenna show return loss less than -12 dB in the whole UWB bandwidth. Linearity of the reflection coefficient phase product have also been achieved. Radiation patterns of the antenna measured at three selected frequency points indicated regular, approximately omni directional...
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Interactive Query Expansion with the Use of Clustering by Directions Algorithm
PublicationThis paper concerns Clustering by Directions algorithm. The algorithm introduces a novel approach to interactive query expansion. It is designed to support users of search engines in forming web search queries. When a user executes a query, the algorithm shows potential directions in which the search can be continued. This paper describes the algorithm and it presents an enhancement which reduces the computational complexity of...
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The (Un)Real City by Magdalena Abakanowicz: Guidelines for Cities in Times of Planetary Crisis
PublicationThree decades have passed since Magdalena Abakanowicz presented her concept of Bois de Nanterre — Arboreal Architecture, in response to a call for a broader reflection on approaches to urban landscaping and a reinterpretation of the meaning and evolution of the Grand Axis in Paris. This paper analyses the work presented by the artist from an urban planning perspective. It shows how the rich and multi-layered metaphor for the 21st-century...
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Impact of high temperature drying process on beech wood containing tension wood
PublicationThe technology of high temperature drying has a great inuence on dimensional and selected physical changes in tension wood. Article is focused on the measurement properties such as moisture content, color changes and longitudinal warping. The quality of beech wood is determined based on structure and properties of wood, frequency of defects in wood material. The tension wood is considered as an important wood defect causing negative...
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ANALYSIS OF THE LOAD-CARRYING CAPACITY OF A HYDRODYNAMIC WATER-LUBRICATED BEARING IN A HYDROELECTRIC POwER PLANT
PublicationThe paper presents an analysis of the load-carrying capacity of a historic hydrodynamic water-lubricated radial bearing of an unconventional segment design installed in the Braniewo Hydroelectric Power Plant. The aim of the calculations was to determine whether the bearing operates in the conditions of hydrodynamic or mixed lubrication, as well as to establish the optimal geometry of the axial grooves allowing for the highest load-carrying...
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Modeling and simulation of blood flow under the influence of radioactive materials having slip with MHD and nonlinear mixed convection
PublicationRadioactive materials are widely in industry, nuclear plants and medical treatments. Scientists and workers in these fields are mostly exposed to such materials, and adverse effects on blood and temperature profiles are observed. In this regard, objective of the current study is to model and simulate blood based nanofluid with three very important radioactive materials, named as Uranium dioxide (UO2), Thorium dioxide (ThO2) and...
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Efektywność i skuteczność studiów doktoranckich w publicznym szkolnictwie wyższym w Polsce
PublicationW artykule podjęto próbę oszacowania efektywności studiów doktoranckich w 58 publicznych szkołach wyższych w latach 2010–2015 za pomocą modelu hybrydowego (łączącego podejście radialne i nieradialne) należącego do nieparametrycznej metody DEA. Dokonano również oceny skuteczności bezpośredniej (od rozpoczęcia studiów do uzyskania stopnia naukowego doktora) i pośredniej (od rozpoczęcia studiów do wszczęcia przewodu doktorskiego)...
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A concept of software extension of 3D low-PRF radar systems to 4D semi-medium-PRF radar systems
PublicationWe present a concept of software modification of three-dimensional (3D) radar systems, designed to work in the low pulse repetition frequency mode, that equips them with the ability to estimate the radial velocity and to properly measure the range of targets that are detected outside the radar’s instrumented range. Despite the fact that the proposed modifications are designed so as to require only minor changes in software, they...
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A multistage turbine for a micro power plant
PublicationThis paper presents results of a design analysis of a multi-stage turbine for the cogeneration micro-power plant working in accordance with Organic Rankine Cycle (ORC). The heat power of the plant is assumed equal to 20 kW and the corresponding available electric output is estimated to be of about 3 kW. Different variants of the radial and axial-flow turbines have been considered, while the detailed results of the calculations...
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THE INFLUENCE OF HOUSING ARRANGEMENT AND INTERFERENCE ON PRELOAD AND THEORETICAL LIFETIME OF A SYSTEM OF TAPER ROLLER BEARINGS OF A HIGH SPEED SHAFT OF A WIND TURBINE GEARBOX
PublicationA system of two taper roller bearings can carry loads with a high ratio of axial load to radial load. Such a system was proposed for a wind turbine gearbox following the poor durability of original bearing design with the aim of increasing durability. Because of size limits, a proposed system is composed of two different taper roller bearings. Standard manufacturers’ catalogues do not provide information on recommended preload...
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Buckling resistance of a metal column in a corrugated sheet silo - experiments and non-linear stability calculations
PublicationThe results of experimental and numerical tests of a single corrugated sheet silo column’s buckling resistance are presented in this study. The experiments were performed in a real silo with and without bulk solid (wheat). A very positive impact of the bulk solid on the column buckling resistance occurred. The experimental results were first compared to the buckling resistance calculated by Eurocode 3 formulae. The comparison revealed that...
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Metropolie ery cyfrowej- wpływ nowych technologii informacyjnych i komunikacyjnych na kształt współczesnego miasta = Digital metropolis - the impact of new information and communication technologies on contemporary city
PublicationDynamiczny rozwój technologii informacyjnych i cyfrowych zapoczątkowany w drugiej połowie XX wieku wpłynął na zmianę wizerunku współczesnego miasta. Coraz bardziej wyraźną rolę w jego tworzeniu zaczęły odgrywać fasady, powłoki budynków oraz fragmenty przestrzeni publicznych, w obrębie których zaczęto integrować pojawiające się innowacyjne technologie, potocznie zwane medialnymi. Powierzchnie architektoniczne wyposażone w nie...
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Novel structure and design of enhanced-bandwidth hybrid quadrature patch coupler
PublicationA novel structure and design optimization procedure of an enhanced-bandwidth hybrid quadrature patch coupler is proposed. Improved performance of the circuit has been obtained by parameterizing the coupler sections using splines, which introduces additional degrees of freedom. Due to computational complexity of the parameter adjustment problem, a sequential design procedure is applied. In each iteration, a selected number of spline...
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A new approach to cross-bonding in medium voltage cable lines
PublicationThe medium voltage underground cable sheaths are usually bonded and earthed in every substation on the cable route. This results in additional power losses in the sheaths. The paper presents an idea of reducing power losses caused by sheaths cross-bonding. The idea of sheaths cross-connecting only in selected MV/LV substations is given instead of a typical solution, where sheaths cross-bonding requires installing additional joints...
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Detection of Objects Buried in the Sea Bottom with the Use of Parametric Echosounder
PublicationThe paper contains results of a in situ research main task of which was to detect objects buried, partially or completely, in the sea bottom. Object detecting technologies employing acoustic wave sources based on nonlinear interaction of elastic waves require application of parametric sound sources. Detection of objects buried in the sea bottom with the use of classic hydroacoustic devices such as the sidescan sonar or multibeam...
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A method of selecting light sources from night satellite scenes
PublicationSatellite images carries a lot of data. Very sophisticated methods of analyses may reveal very complicated nature of the observed objects. In case of night images, lights play the role of information sources. In this paper we would like to present results of the research aimed to describe light sources from satellite night images by providing description of their luminosity. The authors point source imaging data from the satellite...
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Comparision of two numerical methods for buried steel culverts made of corrugated shell sheets.
PublicationW pracy omawia się dwie metody analizy statycznej obudowy tuneli i przepustów dużej średnicy. Pierwsza z nich, metoda sprężyn polega na modelowaniu ośrodka gruntowego radialnymi sprężynami reprezentującymi odkształcalność gruntu. Drugie podejście oparte jest na zastosowaniu metody elementów skończonych i programu SOFISTIC. W układzie obudowa - grunt obudowę modeluje się zwykłymi ramowymi elementami sprężystymi a otaczający...
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Torsional stability capacity of a nano-composite shell based on a nonlocal strain gradient shell model under a three-dimensional magnetic field
PublicationThis paper considers a single-walled composite nano-shell (SWCNS) exposed in a torsional critical stability situation. As the magnetic field affects remarkably nanostructures in the small size, a three-dimensional magnetic field is assessed which contains magnetic effects along the circumferential, radial and axial coordinates system. Based on the results of the nonlocal model of strain gradient small-scale approach and the first-order...
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The use of plate springs for preloading of a system of tapered roller bearings of a wind turbine gearbox
PublicationThe use of preloaded tapered roller bearings in wind turbine drive systems allows a transfer of load in the case of high variations of axial forces. The examined bearing system, a modification of a current design, consists of a pair of different sized bearings. Previous study showed the high sensitivity of tapered roller bearings on the existing radial interference. Dimensional tolerances used in the original design do not allow...
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Relativistic two-dimensional hydrogen-like atom in a weak magnetic field
PublicationA two-dimensional (2D) hydrogen-like atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first- and second-order Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The second-order calculations are...
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Reliability model of slide bearings with particular attention given to lubricating oil
PublicationThe paper presents the slide bearing with circulating lubrication as a system of series three-element structure, where lubricating oil is the weakest link. In accordance with the Pierce statement that ''strength of chain is the strength of its weakest link'', a bearing reliability model has been developed. It allows to use the lubricating oil to evaluate the probability of correct working of the whole slide bearing, i.e. the reliability....
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High Temperature Drying Process of Beech Wood (Fagus sylvatica L.) with Different Zones of Sapwood and Red False Heartwood
PublicationThis study examined the changes in the properties of beech wood (Fagus sylvatica L.) after intense drying. Beech wood with false red heartwood was selected as the test specimen. The test samples had dimensions of 50 mm thickness, 180 mm width, and 350 mm length. The specimens were divided into two groups, false red heartwood and sapwood. These specimens were selected with different angles of the growth rings (radial and tangential)....
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RESEARCH ON HYDRODYNAMIC PEEK JOURNAL BEARINGS LUBRICATED WITH WATER AND OIL
PublicationThe main purpose of the research was to determine the possibilities and experimentally test the benefits of replacing conventional oil lubrication with ecological water lubrication. Tests were carried out on a test rig for hydrodynamic radial bearings under conditions representative of the expected applications for the bearing in water turbines. Bearings made from the polymer material PEEK (polyether ether ketone) were tested under static...
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Investigation of the Effect of The Temperature and Magnetization Pattern on Flux Density, Instantaneous Torque, Unbalanced Magnetic Forces of a Surface Inset PMM
PublicationElectrical machines utilized in domestic applications such as ceiling fans should have low losses and cost. Permanent magnets are used instead of rotor excitation to reduce losses. Therefore, not only the losses of the rotor winding are eliminated, but also the efficiency of the machine is increased. A surface inset consequent pole (SICP) machine has also been used to reduce costs. Because less magnets are utilized in this structure....
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A subdomain model for armature reaction field and open‐circuit field prediction in consequent pole permanent magnet machines
PublicationIn this paper, the machine quantity, such as electromagnetic torque, self and mutual inductances, and electromotive force, is analytically calculated for non-overlapping winding consequent pole slotted machine for open-circuit field and armature reaction. The sub-domain approach of (2-D) analytical model is developed using Maxwell's equations and divide the problem into slots, slot-openings, airgap and magnets region, the magnet...