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Search results for: CALCULATION MODEL
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Comparison of calculation models’ estimates with actual measured autogenous shrinkage in High-Performance Cement Composites
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Barkhausen Noise Calculation by Hysteresis Model Parameters
PublicationPętla histerezy natężenia efektu Barkhausena wyliczono wykorzystując model histerezowy. Założono, iż straty energii na efekt Barkhausena zależą od szybkości granicy domenowej oraz od częstości występowania skoków Barkhausena. Pokazano wyliczenia wykonane dla stali Fe-Si (ziarna zorientowane w kierunku [100] względem kierunku walcowania)
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Calculation of self and mutual inductances of the switched reluctance machine mathematical model.
PublicationA mathematical model of the switched reluctance machine (SRM) in a drive system obtained using Lagrange's energy method and a method of calculation of self and mutual inductances of the SRM are presented in the paper. The self and mutual inductances are elements of Lagrange's function in generalised coordinates and have been calculated using the finite element method (FEM). Selected calculation results for the particular machine...
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Model of the reciprocating engine using iterative procedures of the transient torque calculation
PublicationPrzedstawiony w pracy model silnika spalinowego uzależnia wartość dynamicznego momentu od sygnału sterowania po skokowej zmianie nastawy oraz od historii dynamicznej silnika i czasu jaki upłynął od tej zmiany. Przedstawione wyniki badań potwierdzają zasadność takiego opisu modelowanego zjawiska. Można również zauważyć, że po pewnym czasie od chwili rozpoczęcia procesu rozpędzania przebieg momentu dynamicznego będzie przebiegał...
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The model of end-to-end call setup time calculation for Session Initiation Protocol
PublicationEnd-to-end call setup delay is one of the most important grade of service (GoS) parameters for VoIP networks with Session Initiation Protocol (SIP). A typical subscriber wants to have a connection established as soon as possible. From the operator's perspective call setup time is also crucial because he needs to know how probability of successful packet transmission on SIP links is related to a call setup delay. Then he can make...
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Multi-nodal PWR reactor model — Methodology proposition for power distribution coefficients calculation
PublicationIn the paper the multi-nodal Pressurized Water Reactor (PWR) model called Mann’s model is presented. This models is used for modelling purposes of the heat transfer from fuel to coolant in reactor core. The authors expand widely used in literature approach by defining additional coefficients for the heat transfer model. These parameters approximate the power generation distribution in the PWR reactor core according to the to the...
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A Conception of Pairwise Comparisons Model for Selection of Appropriate Body Surface Area Calculation Formula
PublicationBody surface area (BSA) may be computed using a variety of formulas, but the computed BSA differs from real BSA values for particular subjects. This is presented in the paper by computing BSA values for selected subject and comparing them to the real BSA value obtained with the use of a 3D body scanner. The results show inequalities in the relevant BSA computing formulas. Hence, there is a need to determine a method that will allow...
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How much a geometrical model of a honeycomb seal can be simpli ed in the CFD calculation
PublicationThis paper presents the inuence of geometry simplication on the results obtained in the computational fluid dynamics simulation. The subject of simulation was part of the honeycomb seal located at the inlet to high pressure part of a steam turbine. There were three different geometrical models assumed in the calculations. First one was two-dimensional case and two others were three dimensional, one with the radius of curvature...
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Mathematical model of the energy consumption calculation during the pine sawn wood (Pinus sylvestris L.) drying process
PublicationThe article presents the modification of the existing mathematical model to calculate energy consumption during conventional drying process. Apart from energy consumption the model permits to estimate the time of high-temperature drying process. The drying medium is air and superheated steam mixture. The obtained calculation results were compared with conducted experimental tests of drying square-edged sawn sapwood timber (Pinus...
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Measurements and calculation of self inductance of testing coils used in physical transformer model construction and its frequency analysis
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Software for calculation of noise maps implemented on the supercomputer
PublicationThis paper presents investigation results relevant to the implementation of the algorithms for the calculation of noise maps. The aim of the implementation of the algorithms on the computer cluster is explained. Selected implementation details of the software called the noise propagation model are described. The interaction of the software with the data acquisition system is presented. Noise maps obtained by exploitation of the...
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Earth wires currents calculation by tableau analysis
PublicationThe paper presents a new method to compute a phase-to-earth fault current distribution in overhead transmission line. The method is based on the tableau analysis of an unbalanced, multi-wire model of a transmission line. It allows for the calculation of current distribution in overhead earth wires along the transmission line. Additionally, it may be used to calculate currents in a tower’s earthing system as well as voltages over...
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Displacement piles - classification and methods for the calculation of bearing capacity.
PublicationDisplacement piles belong to a group of technologies whose main idea is to install or make a pile without extracting ground material. According to definition, contained in PN-EN:1997-1:2008, displacement piles should be considered as driven, pressed in using vibrators and made with the use of spread augers. The classification of piles used so far with regard to the technology of execution is modified. An additional element is the...
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Calculation of the propagation loss in urban radio-access systems
PublicationZweryfikowano eksperymentalnie modele propagacyjne opracowane dla telefonii komórkowej w mieście, stosowane przy analizach projektowych systemów dostępowych. Przeprowadzono obszerne badania pomiarowe i zebrano prawie 19 tys. pomiarów. Na tej podstawie, stosując wielowymiarową analize regresji oraz zaproponowaną charakterystykę propagacyjną radiowych łączy dostępowych, opracowano nowy wielowariantowy model propagacyjny przeznaczony...
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Calculation of motion trajectory and geometric parameters of the trawl during pelagic fishing
PublicationThis paper presents a mathematical model of the mass centre motion trajectory of the trawl, its main geometrical parameters, way of solving the model as well as its example results. It could be useful to define optimum parameters of safe, effective and environmentally friendly pelagic fishing.
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Determination of equivalent circuit parameters of an induction motor using field calculation software
PublicationSimulation of the drive system comprising a power electronic converter and an induction motor requires that the equivalent circuit parameters of the motor are known. These parameters can be either measured or calculated. A method of calculation of self and mutual inductances that are parameters of a polyphase model of the motor is presented in the paper. All self-inductances and mutual inductances have been calculated using the...
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Resonance Frequency Calculation of Spherical Microstrip Structure Using Hybrid Technique
PublicationIn this paper the spherical microstrip structure is considered. The structure is composed of a metallic patch with an arbitrary shape placed on a dielectric coated metallic sphere. In the analysis the hybrid technique is utilized. In this approach the finite-difference technique is applied in a cavity model to determine the current basis functions on the patch. Next, using method of moments, the resonance frequency of the structure...
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Improvement of Thrust Bearing Calculation Considering the Convectional Heating within the Space between the Pads
PublicationA modern thrust bearing tool is used to estimate the behavior of tilting pad thrust bearings not only in the oil film between pad and rotating collar, but also in the space between the pads. The oil flow in the space significantly influences the oil film inlet temperature and the heating of pad and collar. For that reason, it is necessary to define an oil mixing model for the space between the pads. In the bearing tool, the solutions...
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The measurement and calculation of gas temperature inside a switchgear during fault arc period.
PublicationW artykule przedstawiono metodę obliczania temperatury gazu wewnątrz rozdzielnicy szczelnej z izolacją powietrzną podczas zwarć łukowych w oparciu o równanie przewodnictwa cieplnego. Przedstawiono wyniki badań eksperymentalnych temperatury gazów podczas zwarć z łukiem wędrującym. Opisano model do badań, układ probierczy i warunki badań. Wyniki obliczeń porównano z wynikami badań eksperymentalnych.
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Verification of Selected Calculation Methods Regarding Shear Strength in Reinforced and Prestressed Concrete Beams
PublicationThe purpose of this article was an attempt to compare selected calculation methods regarding shear strength in reinforced and prestressed concrete beams. Several calculation methods were tested. This included codes: PN-EN 1992-1-1:2008 [1], ACI 318- 14 [2] and fib Model Code for Concrete Structures 2010 [3]. The analysis also consists of methods published in technical literature. Calculations of shear strengths were made based...
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Verification of selected calculation methods regarding shear strength in beams without web reinforcement
PublicationThe purpose of the article was to compare selected calculation methods regarding shear strength in reinforced concrete beams without web reinforcement. Several calculation methods were tested. This included codes: PN-EN 1992-1-1:2008, ACI 318-14 and fib Model Code for Concrete Structures 2010. The analysis also consists of authorial methods published in technical literature. Calculations of shear strengths were made based on experimental...
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Service time distribution influence on end-to-end call setup delay calculation in networks with Session Initiation Protocol
PublicationThe most important GoS parameter for networks with SIP protocol is end-to-end call setup delay. So far there were no coherent models allowing calculation of these parameters for networks with SIP protocol. Few models were developed but they are insufficient. In the paper we propose model which allows end-to-end call setup delay calculation for networks with SIP protocol. The model is using chain of M/G/1/K models and is applicable...
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Calculation of electron scattering lengths on Ar, Kr, Xe, Rn and Og atoms
PublicationFocusing on the noble gases, we calculate the scattering potential using the Dirac-Coulomb Hamiltonian supplemented with a model polarization potential. We determine the scattering lengths using two methods, namely phase shifts for very small scattering energies and the shape of the wave function for zero scattering energy. We compare our theoretical electron scattering length results on Ar, Kr and Xe atoms with existing experimental...
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Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards
PublicationIn the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulation and evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modeling and solution rely on finite element methods and cover the simulation of the structure’s properties along with the influence of the marine environment – sea currents, wave and wind loading,...
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A new viscoelastic method of calculation of low-temperature thermal stresses in asphalt layers of pavements
PublicationThe paper presents a new method of calculation of thermal stresses in asphalt layers of pavements induced by cooling or heating. The method, developed by the author, is based on the analytical solution for the linear viscoelastic Burgers model extended numerically for the case of asphalt layers whose rheological parameters are strongly dependent on temperature. The coefficient of thermal expansion and Poisson’s ratio may optionally...
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Improvement of the thrust bearing calculation considering the convectional heating within the space between the pads
PublicationA modern thrust bearing calculation tool should consider not only the oil film between pad and rotating collar but also the space between the pads. The oil flow in the space has a significant influence on the oil film inlet temperature, the convectional cooling of pad and collar and should be included in the bearing calculation methods. The authors use a tool developed at Clausthal University of Technology in cooperation with the...
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Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards
PublicationIn the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulationand evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modelingand solution rely on finite element methods and cover the simulation of the structure’s properties along with the influenceof the marine environment – sea currents, wave...
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Verification of the new viscoelastic method of thermal stress calculation in asphalt layers of pavements
PublicationThe new viscoelastic method of thermal stress calculations in asphalt layers has been developed and published recently by the author. This paper presents verification of this method. The verification is based on the comparison of the results of calculations with results of testing of thermal stresses in Thermal Stress Restrained Specimen Test. The calculations of thermal stresses according to the new method were based on rheological...
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Calculation method for flow boiling and flow condensation of R134a and R1234yf in conventional and small diameter channels
PublicationThe paper presents the results of calculations performed using the authors’ model to predict the heat transfer coefficient during flow boiling for two refrigerants R134a and R1234yf. The experimental data from various past studies have been collected and the calculations have been conducted for the full range of quality variation and a wide range of mass velocity. The aim of the study was to test the sensitivity of the in-house...
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Resonance Frequency Calculation of a Multilayer and Multipatch Spherical Microstrip Structure Using a Hybrid Technique
PublicationThis communication offers a rigorous analysis of the resonance frequency problem of a spherical microstrip structure mounted on a multilayer, dielectric-coated metallic sphere, with an electrically small radius. The structure consists of single or multiple metallic patches with arbitrary shapes. A full-wave analysis is employed with the use of proposed hybrid approach, combining the finite-difference technique with a spectral domain...
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Novel Binary Mixtures of Alkanolamine Based Deep Eutectic Solvents with Water—Thermodynamic Calculation and Correlation of Crucial Physicochemical Properties
PublicationThis paper demonstrates the assessment of physicochemical and thermodynamic properties of aqueous solutions of novel deep eutectic solvent (DES) built of tetrabutylammonium chloride and 3-amino-1-propanol or tetrabutylammonium bromide and 3-amino-1-propanol or 2-(methylamino)ethanol or 2-(butylamino)ethanol. Densities, speeds of sound, refractive indices, and viscosities for both pure and aqueous mixtures of DES were investigated...
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Novel binary mixtures of alkanolamine based deep eutectic solvents with water - thermodynamic calculation and correlation of crucial physicochemical properties
PublicationThis paper demonstrates the assessment of physicochemical and thermodynamic properties of aqueous solutions of novel deep eutectic solvent (DES) built of tetrabutylammonium chloride and 3-amino-1-propanol or tetrabutylammonium bromide and 3-amino-1-propanol or 2-(methylamino)ethanol or 2-(butylamino)ethanol. Densities, speeds of sound, refractive indices, and viscosities for both pure and aqueous mixtures of DES were investigated...
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Calculation of adiabatic potentials of Li2
PublicationPrezentujemy adiabatyczne krzywe energii potencjalnej jonu cząsteczki litu. Krzywe zostały stabelowane według odległości międzyatomowej: od 2ao do 100ao. Nasze teoretyczne wyniki zostały porównane z wynikami innych autorów oraz z krzywymi potencjałów energii uzyskanymi w wyniku eksperymentów. Wszystkie obliczenia zostały wykonane przy użyciu programu MOLPRO.
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Calculation of adiabatic potentials of Li2
PublicationInformujemy o adiabatycznych krzywych energii potencjalnej cząsteczki litu. Nasze krzywe są stabelowane według odległości międzyatomowej od 3,2 a0 do 88a0. Porównujemy nasze wyniki teoretyczne z wynikami obliczonymi przez innych autorów oraz krzywymi energii potencjalnej wyprowadzonymi z eksperymentów. W naszym podejściu używamy metody konfiguracji wzajemnego oddziaływania, gdzie tylko elektrony walencyjne atomu Li są traktowane...
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Implementation of TVDI calculation for coastal zone
PublicationPaper will show an implementation of TVDI (Temperature-Vegetation-Dryness Index) algorithm on GPU (Graphics Processing Unit). Calculation of this index is based on LST (Land Surface Temperature) and NDVI (Normalized Difference Vegetation Index). Discussed results are based on multi-spectral imagery retrieved from AVHRR3 sensors for area of Poland, especially from region of Gdańsk coastal zone. All phases of TVDI implementation...
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Microscopic calculation of the energetics of ions in polyethylene
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On numerical calculation of acoustic field of plane source.
PublicationSkładowe harmoniczne wiązki akustycznej zostały obliczone na podstawie reprezentacji w postaci całek według teorii reprezentacji. Zastosowano nowe metody do obliczania całek od funkcji szybko oscylacyjnych.
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Calculation of vibrational spectra for cyanobiphenyl liquid crystals
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Microscopic calculation of the static electric susceptibility of polyethylene
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An approach to improve the time efficiency of disjoint paths calculation
PublicationFailures of network elements can be appropriately dealt with by utilization of alternate disjoint paths to provide redirection of flows affected by failures of the respective working paths. Known approaches can be broadly divided by decision on backup paths installation into proactive and reactive mechanisms, as well as based on the scope of recovery actions into local and global rerouting. There are several important scenarios...
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Reprezentation of mechanic hysteresis in a railway track using the Preisach model
PublicationThis paper presents an implementation of the classic scalar Preisach model to describe the hysteresis phenomenon created in a railway track subjected to lateral (in the horizontal plane) displacements. The principles of the Preisach theory and the scalar mathematical model of the mechanical hysteresis that is based on statistically distributed modified hysteresis operators are briefly presented. This article presents the characteristic...
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Application of Mazur-Orlicz`s theorem in AMISE calculation
PublicationW pracy podano nowe wyprowadzenie formuły asymptotycznej błędu aproksymacji dla operatorów całkowych w przestrzeniach niezmienniczych na przesunięcia. Obliczono asymptotykę błędu średniokwakratowego dla estymatora gęstości.
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Usability of calculation methods for saw blade stiffness determination.
PublicationW pracy przedstawiono metodykę wyznaczania sztywności poprzecznej pił określanej na linii zębów. Prezentowana metodyka może być wykorzystywana zarówno do pił trakowych jak i taśmowych. Podano zalecenia wyboru odpowiedniej metody obliczeniowej w zależności od szerokości brzeszczotu piły.
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The influence of dimensional accuracy on steel structures cost calculation
PublicationW referacie przedstawiono zależność pomiędzy wartością tolerancji a kosztami wytwarzania budowlanych konstrukcji stalowych. Opisano zasady klasyfikacji tolerancji prętowych konstrukcji stalowych z uwagi na porawny montaż konstrukcji wyrażony równaiem pętli montażowej. Przedstawiono podstawy analizy i syntezy tolerancji oraz zaproponowano nową formułę optymalizacji kosztów wytwarzania. Wskazano metody rozwiązania zadania optymalizacyjnego.
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Evaluation of time-efficiency of disjoint paths calculation schemes
PublicationThe concept of alternate paths has been shown in the literature to provide fast response of a network to failures of its elements (nodes/links) affecting flows along the primary communication paths. Various approaches have been proposed to reduce the time necessary to redirect the respective flows onto the alternate paths. In this paper, we focus on another important objective, that so far has not received much attention, i.e.,...
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Toward Fast Calculation of Communication Paths for Resilient Routing
PublicationUtilization of alternate communication paths is a common technique to provide protection of transmission against failures of network nodes/links. However, a noticeable delay is encountered when calculating the relevant sets of disjoint paths using the available algorithms (e.g., using Bhandari’s approach). This, in turn, may have a serious impact on the ability of a network to serve dynamic demands...
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Computational methods for calculation of binding free energy for ligand-receptor complexes
PublicationAccurate description of the molecular complexes energetic influence is required for understanding of many biological functions carried out by proteins. Therefore, estimation of binding free energy for ligand-receptor complexes is of highest importance for structure-based ligand design and drug discovery approaches.Experimental methods of determination of difference in Gibbs'es free energy have many limitations. Thus, computational...
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GlyCulator2: an update on a web application for calculation of glycemic variability indices
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Improved methods for stator end winding leakage inductance calculation
PublicationCalculating the stator end-winding leakage inductance, taking into account the rotor, is difficult due to the irregular shape of the end-winding. The end-winding leakage may distribute at the end of the active part and the fringing flux of the air gap. The fringing flux belongs to the main flux but goes into the end-winding region. Then, not all the magnetic flux occurring in the end region is the end-winding leakage flux. The...
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On the influence of the acceleration recording time on the calculation of impact severity indexes
PublicationThe paper concerns with the analysis of normative requirements pertaining to experimental setup of a crash test and its numerical modelling. An overview of parameters describing the collision of a vehicle with a road restraining system is presented. A short description of a concrete road safety barrier is presented. A brief description of numerical modelling procedures for crash tests is given as well. The parametric influence...