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Search results for: dft%20calculations
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One Europe, one product, two prices - the price disparity in the EU
PublicationThe price dispersion in the European Union in the last fifteen years (1990-2005) is analysed. The analysis of price convergence is examined on aggregate and disaggregate levels. The macro approach is based on Comparative Price Level index calculated as the ratio between PPPs and exchange rate. The disaggregate analysis utilizesactual prices of 148 individual products sold in the 15 capital cities of the EU. The calculations comprise...
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Superconducting properties and electronic structure of NaBi
PublicationResistivity, dc magnetization, and heat capacity measurements are reported for superconducting NaBi. Tc, the electronic contribution to the specific heat γ, the ΔCp/γTc ratio, and the Debye temperature are found to be 2.15 K, 3.4 mJ mol−1 K−2, 0.78, and 140 K respectively. The calculated electron–phonon coupling constant (λep = 0.62) implies that NaBi is a moderately coupled superconductor. The upper critical field and coherence...
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Molecular geometry and optical activity of helically chiral N-nitrosamines derived from 1,2,3,4-tetrahydro- and 1,2,3,4,7,8,9,10-octahydro-1,10-phenanthroline
PublicationX-ray crystallographic analysis of the title N-nitrosamines revealed that they assume helical conformations in the solid state. Nitrosamines 1b and 2b were resolved by inclusion crystallization with optically active diols (TADDOLs). The absolute configuration of the guest molecules in the complexes 1b·3b and 2b·3b was assigned as M. The optical activity of the resolved compounds is manifested by their solid state CD spectra, which...
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Sensitivity analysis of a composite footbridge
PublicationThis 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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New Generation of Water lubricated Foil bearing - Numerical Models and Experimental Verification
PublicationIn the paper a new idea of foil water lubricated bearing and methodology of hydrodynamic characteristics calculations is presented. To assesses the theoretical characteristics of these bearings two different computer models were built. First is structural model coupled with fluid model. It takes into account: fluid flow in the deformed fluid gap, specific design of bearing support and friction in bearing support. The second is...
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Polyarmonic model of synchronous generator for analysis of autonomous power generation systems
PublicationAbstract: This paper presents the polyharmonic modelling of synchronous generator (SG) in machine variables. The simple geometry and windings physical layout has been used for inductance calculations of a salient-pole SG. The main advantage of this model is the ease of describing an autonomous power generation system (APGS) in terms of its topology and thus providing effective analysis at the static and dynamic states, both for...
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Numerical modeling of GPR field in damage detection of a reinforced concrete footbridge
PublicationThe paper presents a study on the use of the ground penetrating radar (GPR) method in diagnostics of a footbridge. It contains experimental investigations and numerical analyses of the electromagnetic field propagation using the finite difference time domain method (FDTD). The object of research was a reinforced concrete footbridge over a railway line. The calculations of the GPR field propagation were performed on a selected cross-section...
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Dipole-driven dynamics for near-threshold electron/positron interactions with pyrimidinic DNA bases: a path to compound formations
PublicationCalculations are reported for electron and positron scattering from isolated cytosine and thymine, where the two pyrimidinic single-ring DNA bases, in the gas-phase at energies near the elastic threshold, they reveal the special features of the dipole-driven scattering states. All molecules examined exhibit, in fact, supercritical (>1.67 D) permanent dipoles which can therefore also support, below threshold, excited bound compound...
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COMPUTER ANALYSIS OF HYDRAULIC CONDITIONS IN A SANITARY CHAMBER
PublicationThis paper presents analysis of hydraulic conditions of sewage flow down the slipway (ramp) in the collecting sanitary chamber connecting 3 collectors on the inlet: ⌀600, ⌀800 and ⌀1400 and one on the outlet ⌀1600 mm, with a maximum difference of elevation 5 m. The mathematical model has been made and hydraulic calculations were carried out in steady flow conditions. Then wastewater surface elevation, energy grade line elevation,...
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Dissociative electron attachment and anion-induced dimerization in pyruvic acid
PublicationWe report partial cross sections for the dissociative electron attachment to pyruvic acid. A rich fragmentation dynamics is observed. Electronic structure calculations facilitate the identification of complex rearrangement reactions that occur during the dissociation. Furthermore, a number of fragment anions produced at electron energies close to 0 eV are observed, that cannot originate from single electron-molecule collisions....
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Simplified Method of Modelling Behaviour of Ship in Waves with Partially Flooded Compartments
PublicationThis paper contains a description of a numerical model for calculating behaviour of ships in waves. There are many models available, but the one described here can be characterised with a set of parameters that have a decisive impact on the final values of roll motion amplitude and frequency. In this paper, it is shown how a fitting of a standard-shape hull characterised by certain readily available parameters affects...
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Sum-over-state expressions including second-order Herzberg–Teller effects for the calculation of absorption and resonance Raman intensities
PublicationThe sum-over-state expressions are derived to calculate the second-order Herzberg–Teller (HT) effects in absorption and resonance Raman spectroscopies. These effects depend on the second derivatives of the transition dipole moment with respect to the vibrational coordinates. The method is applied to the molecule of 1,3-butadiene using density functional theory calculations. It is found that the second-order HT effects are significant...
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Environmentally acceptable lubricants (EAL) compared with a reference mineral oil as marine stern tube bearing lubricant – Experimental and theoretical investigations
PublicationThe purpose of this research is to indicate the potential differences in bearing characteristics resulting from the application of different lubricant types with the same viscosity grade. The effect of different environmentally acceptable lubricants (EALs) on hydrodynamic journal bearing properties is studied experimentally and compared to the properties obtained after lubrication with a reference mineral oil. The results of the...
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A study about daylighting knowledge and education in Europe. Results from the first phase of the DAYKE project
PublicationThis paper presents selected results from the first stage of DAYKE (Daylight Knowledge in Europe), a 3- phase project that investigates the knowledge on daylighting in buildings among architecture students and practitioners across Europe. Subjective judgements from 561 students from 8 architecture universities in the EU, collected through two surveys in 2018. The key findings are: (i) the spatial distribution of comfort and mood...
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Improved magnitude estimation of complex numbers using alpha max and beta min algorithm
PublicationThe paper presents an improved algorithm for calculating the magnitude of complex numbers. This problem, which is a special case of square rooting, occurs for example, in FFT processors and complex FIR filters. The proposed method of magnitude calculation makes use of the modified alpha max and beta min algorithm. The improved version of the algorithm allows to control the maximum magnitude approximation error by using an adequate...
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Systemy Wspomagania Zarządzania Należnościami (DRMS) jako nowa klasa systemów informatycznych
PublicationW polskim obrocie gospodarczym powszechnym zjawiskiem stało się niepłacenie przez dłużników swoich zobowiązań. Dla wierzyciela kluczowym procesem biznesowym staje się zarządzanie swoimi należnościami, od skuteczności którego zależy niejednokrotnie utrzymanie przezeń płynności finansowej. By zarządzanie owo było efektywne, niezbędny jest stały monitoring wielu informacji w firmie - począwszy od analizy kwot i dat wymagalności faktur,...
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Protokół SIP i jego implementacja
PublicationW pracy została przedstawiona zrealizowana implementacja protokołu SIP dla potrzeb czteroportowej wersji Abonenckiego Terminala Kablowego 7410 firmy DGT z wykorzystaniem dostępnych otwartych kodów źródłowych. W referacie zawarto opis ATK, wykorzystane metody wytwarzania oprogramowania dla potrzeb ATK. Następnie przeprowadzono rozpoznanie możliwości implementacji protokołu SIP w ATK i opisano kryteria wymagań w stosunku do tego...
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Protokół SIP i jego implementacja
PublicationW pracy została przedstawiona zrealizowana implementacja protokołu SIP dla potrzeb czteroportowej wersji Abonenckiego Terminala Kablowego 7410 firmy DGT z wykorzystaniem dostępnych otwartych kodów źródłowych. W referacie zawarto opis ATK, wykorzystane metody wytwarzania oprogramowania dla potrzeb ATK. Następnie przeprowadzono rozpoznanie możliwości implementacji protokołu SIP w ATK i opisano kryteria wymagań w stosunku do tego...
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Dobór optymalnej liczby jednostek funcjonalnych dla realizacji syntezy wysokiego poziomu układów cyfrowych
PublicationW pracy przedstawiono algorytm MNP (ang. minimization the number of procesing elements) wyznaczający liczbę jednostek funkcjonalnych niezbędnych do syntezy wysokiego poziomu zadania opisanego grafem przepływu danych (DFG - ang. data flow graph). Liczba jednostek funkcjonalnych wyznaczana przez prezentowany algorytm jest optymalna zarówno z punktu widzenia kosztów wykonania układu, jak i szybkości jego działania. Rozwiązanie tego...
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OFDM modulation and adaptive equalisation for underwater communications.
PublicationWłasności transmisyjne płytkiego kanału podwodnego są ograniczone ze względu na wielokrotne odbicia fal dźwiękowych od dna i powierzchni wody oraz ze względu na niestacionarność powodowaną głównie przez ruch powierzchni wody. W celu minimalizacji wpływu interferencji międzysymbolowych, powodowanych przez wielodrogową propagację fal dźwiękowych, w tradycyjnych wąskopasmowych modemach telekomunikacyjnych stosowane są złożone equalizery...
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DFMA guidelines and a data base system in integrated development of hydraulic pumps
PublicationPrzedstawiono koncepcję budowy systemu decyzyjnego, dla zintegrowanego rozwoju pomp hydraulicznych oraz doboru adekwatnych technik wytworzenia komponentów i procesów montażu, z zastosowaniem metodyki SADT/IDEF0 oraz ogólnych wytycznych DFMA. Omówiono stosowane w przemyśle krajowym konstrukcje pomp zębatych z łożyskami tocznymi oraz udoskonalone rozwiązania projektowe tych pomp z łożyskami ślizgowymi (polimerowymi). Wskazano na...
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Signals features extraction in radioisotope liquid-gas flow measurements using wavelet analysis
PublicationKnowledge of the structure of a flow is significant for the proper conduct of a number of industrial processes. In this case, a description of a two-phase flow regimes is possible by use of the time-series analysis in time, frequency and state-space domain. In this article the Discrete Wavelet Transform (DWT) is applied for analysis of signals obtained for water-air flow using gamma ray absorption. The presented method was illustrated...
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Sterowanie czujnikami pracującymi w sieci zigbee przy pomocy komend glosowych
PublicationPrzedstawiono bezprzewodową sieć sensorową, pobierającą i przekazującą informacje z czujników temperatury i oświetlenia sterowanych głosem. Funkcjonalność systemu może zostać wykorzystana do sterowania urządzeniami automatyki domowej. System składa się z trzech zasadniczych elementów: koordynatora sieci ZigBee, urządzenia końcowego (pomiarowego) wyposażonego w czujniki światła i temperatury oraz komputera PC. Użytkownik może zarządzać...
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Rodniki, utleniacze i przeciwutleniacze
PublicationLiczne procesy chemiczne, enzymatyczne i mikrobiologiczne, zachodzące podczas przechowywania i przetwarzania, mają wpływ na kształtowanie jakości żywności. Istotne znaczenie ma utlenianie przy udziale wolnych rodników i reaktywnych form tlenu (RFT). Zmiany powodowane utlenianiem m.in. pogarszają sensoryczne właściwości i wartość odżywczą żywności oraz mogą wywoływać zagrożenia zdrowotne wynikające ze szkodliwości niektórych produktów...
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Analiza numeryczna i analityczna przekrycia w kształcie powłoki synklastycznej o podstawie kwadratowej
PublicationW pracy poruszono problem obliczania przekrycia żelbetowego w kształcie powłoki synklastycznej ściętej o podstawie kwadratowej. Przedstawiono obliczenia analityczne i numeryczne sił w powłoce. Powłoka jest poddana działaniu głównie sił ściskających, co jest korzystne dla tego typu konstrukcji. W strefie brzegowej i podporowej konieczne jest wymiarowanie na mimośrodowe ściskanie i rozciąganie z uwagi na znaczący wzrost momentów...
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Low-energy electron scattering from molecular hydrogen: Excitation of the X1Σg+ to b3Σu+ transition
PublicationWe present time-of-flight differential cross-section measurements and convergent close-coupling calculations of differential cross sections for the electron-impact excitation of the X 1 g + → b 3 u + transition in molecular hydrogen. A part of this work was recently published [M. Zawadzki et al., Phys. Rev. A 97, 050702(R) (2018)]. In this work, agreement between theory and experiment is excellent overall, and marks a transition...
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Reliability Analysis of Sea Cliff Slope Stability by Point Estimate Method
PublicationThe paper presents a reliability analysis of a sea cliff slope. The cliff, located in Jastrzębia Góra, is characterised by a complicated geological structure. Although currently stable, it is in fact close to the limit state. The objective of this paper is to present the point estimate method (PEM) of determining the mean value and standard deviation of the safety factor of the slope. Assuming its normal distribution, these statistical...
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Evaluation of apparent Young׳s modulus of the composite polymer layers used as sliding surfaces in hydrodynamic thrust bearings
PublicationHydrodynamic bearings with a polymer sliding layer are able to operate in severe conditions, mainly due to favorable properties of the polymers. The goal of this research was to evaluate apparent Young׳s modulus of two types of the polymer composite layers used for sliding surfaces in hydrodynamic bearings, as a function of temperature. The Young׳s modulus was evaluated on the basis of compression tests carried out on samples obtained...
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Analysing selection of low-temperature medium for cogeneration micro power plant
PublicationThe article analyses the ORC system working with dry and wet low-boiling media which are most frequently used in installations of this type. Two types of cycles were examined, which were the cycle with heat regeneration for dry media: fc72, hfe7100, R227ea, R245fa, R423a and R600a, and the cycle without heat regeneration for wet media: R11, R12, R134a, R718 and 507a. The calculations were performed for the assumed required thermal...
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Low-energy positron scattering from gas-phase tetrahydrofuran: A quantum treatment of the dynamics and a comparison with experiments
PublicationIn this paper we report new quantum calculations of the dynamics for low-energy positrons interacting with gaseous molecules of tetrahydrofuran. The new quantum scattering cross sections are differential and integral cross sections at collision energies between 1.0 and 25.0 eV and include a careful treatment of the additional effects on the scattering process brought about by the permanent dipole moment of the target molecule....
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Evaluation of the structures size in the liquid-gas flow by gamma-ray absorption
PublicationThe rapid development of tomography methods particularly electrical, X and gamma rays allows for a wide range of the information about flow structure. However, all of such methods are quite complicated. At the same time much simpler systems as the measuring system of gamma rays absorption, allows to obtain a all key flow information which describe the two-phase flow. In the article the results of analyzes of radiometric signal...
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Awaria ściany szczelinowej stanowiącej obudowę wykopu głębokiego
PublicationW artykule przedstawiono awarię ściany szczelinowej stanowiącej obudowę wykopu głębokiego. Omówiono warunki geologiczne, hydrogeologiczne i geotechniczne podłoża. Przeprowadzono analizę rozwiązań konstrukcyjnych w kolejnych oszczędnościowych modyfikacjach projektu oraz zrealizowanej wersji. Wykonano obliczenia porównawcze. Wskazano przyczyny wystąpienia awarii. In the paper a failure of diaphragm wall protecting deep excavation...
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Ferro- and antiferro-magnetism in (Np, Pu)BC
PublicationTwo new transuranium metal boron carbides, NpBC and PuBC, have been synthesized. Rietveld refinements of powder XRD patterns of {Np,Pu} BC confirmed in both cases isotypism with the structure type of UBC. Temperature dependent magnetic susceptibility data reveal antiferromagnetic ordering for PuBC below T-N = 44 K, whereas ferromagnetic ordering was found for NpBC below T-C = 61 K. Heat capacity measurements prove the bulk character...
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Crystal structure, chemical bonding, and physical properties of layered AIrSn2 (A = Sr and Ba)
PublicationWe report the experimental and theoretical investigation of structure, chemical bonding interactions, and physical properties of new ternary stannides AIrSn2 (A = Sr and Ba). AIrSn2 (A = Sr and Ba) crystallizes in the orthorhombic Re3B-type structure with the space group Cmcm (No. 64). According to single-crystal X-ray diffraction results, the structure of AIrSn2 (A = Sr and Ba) can be considered as a Zintl-type compound with heterogeneous...
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An improved method for flow boiling heat transfer with account of the reduced pressure effect
PublicationIn the paper are presented the results using the authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data to investigate the sensitivity of the in-house developed model. In the work are presented the results of calculations obtained using the semi-empirical model on selected experimental flow boiling data of the refrigerants: R134a, R1234yf,...
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Analysing selection of low-temperature medium for cogeneration micro power plant
PublicationThe article analyses the ORC system working with dry and wet low-boiling media which are most frequently used in installations of this type. Two types of cycles were examined, which were the cycle with heat regeneration for dry media: fc72, hfe7100, R227ea, R245fa, R423a and R600a, and the cycle without heat regeneration for wet media: R11, R12, R134a, R718 and 507a. The calculations were performed for the assumed required thermal...
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A spice equivalent circuit for modeling the performance of dual frequency echo-sounder
PublicationThe paper presents novel network equivalent circuit of piezoceramic circular disc transducers that takes into account thickness and radial 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. The approximate solution for harmonic case is represented in the form of 4x4 matrix, which is synthesised and...
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Process zone in the Single Cantilever Beam under transverse loading. - Part I: Theoretical analysis
PublicationSingle Cantilever Beam (SCB) specimen loaded with a transverse force parallel to the crack front is proposed for the analysis of crack propagation phenomena under mixed mode conditions. The stress redistribution in the adhesive layer in the vicinity of the crack front so as the beam deformation are estimated using a Timoshenko beam on elastic foundation model. This model emphasizes the Mode II contribution due to flexural beam...
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The ranks of Indonesian and Japanese industrial sectors
PublicationThe purpose of this study is to determine the ranks of Indonesian and Japanese industrial sectors from the economic point of view. The analysis period of this study is 2005. This study employs one of the well-known analysis tools in the economic topic, the Input-Output (IO) analysis. More specifically, this study uses the analysis methods in the IO analysis, backward and forward linkages, in order to achieve the purpose. The results...
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Impact of configuration of earth continuity conductor on induced sheath voltages in power cables
PublicationIn high voltage power cable systems a problem of induced sheath voltages exist. Due to these voltages electric shock and damage of non-metallic outer sheath of the cables may occur. Exposure to voltage of the outer sheath may be very high in case of earth fault with high value of earth current. In order to reduce induced sheath voltages an earth continuity conductor (conductors) along power cables is applied. Configuration of this...
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The ranks of Indonesian and Japanese industrial sectors
PublicationThe purpose of this study is to determine the ranks of Indonesian and Japanese industrial sectors from the economic point of view. The analysis period of this study is 2005. This study employs one of the well-known analysis tools in the economic topic, the Input-Output (IO) analysis. More specifically, this study uses the analysis methods in the IO analysis, backward and forward linkages, in order to achieve the purpose. The results...
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Increase of power and efficiency of the 900 MW supercritical power plant through incorporation of the ORC
PublicationThe objective of the paper is to analyse thermodynamical and operational parameters of the supercritical power plant with reference conditions as well as following the introduction of the hybrid system incorporating ORC. In ORC the upper heat source is a stream of hot water from the system of heat recovery having temperature of 90 °C, which is additionally aided by heat from the bleeds of the steam turbine. Thermodynamical analysis...
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Hydrogen migration in formation of NH(A3Π) radicals via superexcited states in photodissociation of isoxazole molecules
PublicationFormation of the excited NH(A 3Π) free radicals in the photodissociation of isoxazole (C3H3NO) molecules has been studied over the 14-22 eV energy range using photon-induced fluorescence spectroscopy. The NH(A 3Π) is produced through excitation of the isoxazole molecules into higher-lying superexcited states. Observation of the NH radical, which is not a structural unit of the isoxazole molecule, corroborates the hydrogen atom...
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Modeling of multi-cavity Fabry-Perot optical fiber sensors
PublicationReflectance characteristics of a two-cavity extrinsic Fabry-Perot optical fiber sensor were investigated using computer modeling. Calculations were performed using a plane wave-based approach, selected for clarity of results. Based on the modeling results, it can be concluded that the two-cavity Fabry-Perot interferometer can be used to measure two different quantities, such as refractive index and temperature, independently. It...
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Diagnosing marine turbine engines through energy characteristics of their flow section
PublicationThe 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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Computational Fluid Dynamic study on the wind characteristics of a multifunctional building system model in developed coastal cities
PublicationThis paper presents an approach for providing innovative technology by applying fluid mechanics to the field of architectural design. The aim is to make a building’s shape profitable and strengthen environmental protection by using the wind force to create an integrated wind absorption definition for a multifunctional building system model. Furthermore, taking control of the wind flow over an object can have an impact on not only...
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Reliability Analysis of Sea Cliff Slope Stability by Point Estimate Method
PublicationThe paper presents a reliability analysis of a sea cliff slope. The cliff, located in Jastrzębia Góra, is characterised by a complicated geological structure. Although currently stable, it is in fact close to the limit state. The objective of this paper is to present the point estimate method (PEM) of determining the mean value and standard deviation of the safety factor of the slope. Assuming its normal distribution, these statistical...
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Mixed, quantum-classical description of electron density transfer in the collision process
PublicationIn this work, we investigate an ion-atom model describing the time-dependent evolution of electron density during the collision. For a S3+- H system, numerical simulations are based on classical trajectory calculations, and the electron density behaviour is described with the time-dependent Schrödinger equation. We apply the finite difference method to obtain quantitative insights into the charge transfer dynamics, providing detailed...
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A new finite element with variable Young's modulus
PublicationThe Finite Element Method (FEM) is a numerical technique that is well-established in the field of engineering. However, in biological sciences, it is justtaking its first steps. Bone tissue is an example of biological material which isexposed to high loads in its natural environment. Practically every movementof the body results in changing stress levels in the bone. Nature copes with thisvery well but when human intervention is...
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Probabilistic estimation of diverse soil condition impact on vertical axis tank deformation
PublicationThe calculations of fuel tanks should take into account the geometric imperfections of the structure as well as the variability of the material parameters of the foundation. The deformation of the tank shell can have a significant impact on the limit state of the structure and its operating conditions. The paper presents a probabilistic analysis of a vertical-axis, floating-roof cylindrical shell of a tank with a capacity of 50000...