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A Fortran-95 algorithm to solve the three-dimensional Higgs boson equation in the de Sitter space-time
Open Research DataA numerically efficient finite-difference technique for the solution of a fractional extension of the Higgs boson equation in the de Sitter space-time is designed. The model under investigation is a multidimensional equation with Riesz fractional derivatives of orders in (0,1)U(1,2], which considers a generalized potential and a time-dependent diffusion...
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Preparation and characterization of rigid polyurethane -polyglycerol nanocomposite foams
PublicationThis work reports on the preparation of polyurethane–polyisocyanurate (PUR–PIR) foams containing different polyglycerols and layered silicate nanoclays. The rigid polyurethane foams were obtained in a laboratory scale, in a single step method, from a two-component system with a NCO to OH groups ratio equal to two. The reaction mixture consisted of the proper amounts of a commercial oligoetherpolyol, polyglycerol, catalysts, water,...
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Crystal structure and electronic structure of CePt2In7
PublicationWe report a corrected crystal structure for the CePt2In7 superconductor, refined from single crystal x-ray diffraction data. The corrected crystal structure shows a different Pt–In stacking along the c-direction in this layered material than was previously reported. In addition, all of the atomic sites are fully occupied with no evidence of atom site mixing, resolving a discrepancy between the observed high resistivity ratio of...
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Bending and buckling formulation of graphene sheets based on nonlocal simple first-order shear deformation theory
PublicationThis paper presents a formulation based on simple first-order shear deformation theory (S-FSDT) for large deflection and buckling of orthotropic single-layered graphene sheets (SLGSs). The S-FSDT has many advantages compared to the classical plate theory (CPT) and conventional FSDT such as needless of shear correction factor, containing less number of unknowns than the existing FSDT and strong similarities with the CPT. Governing...
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Thermal Buckling Analysis of Circular Bilayer Graphene sheets Resting on an Elastic Matrix Based on Nonlocal Continuum Mechanics
PublicationIn this article, the thermal buckling behavior of orthotropic circular bilayer graphene sheets embedded in the Winkler–Pasternak elastic medium is scrutinized. Using the nonlocal elasticity theory, the bilayer graphene sheets are modeled as a nonlocal double–layered plate that contains small scale effects and van der Waals (vdW) interaction forces. The vdW interaction forces between the layers are simulated as a set of linear springs...
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Sessile droplet contact angle of water–Al2O3, water–TiO2 and water–Cu nanofluids
PublicationThis work presents measurements of the contact angle of sessile droplets for three nanofluids, i.e. water–Al2O3, water–TiO2 and water–Cu. The plates made of glass, anodized aluminium and stainless steel of different roughness served as substrates. Ultrasonic vibration was used for 30–60 min in order to stabilise the dispersion of the nanoparticles. Nanoparticles were tested at the concentration of 0.01%, 0.1%, and 1% by weight....
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Roman Śmierzchalski prof. dr hab. inż.
PeopleRoman Śmierzchalski born in 1956 in Gdynia. He received the M.Sc. degree in 1979, the Ph.D. degree in 1989, both from the Gdańsk University of Technology, and the D.Sc. (‘habilitation’) degree in 1999 from the Warsaw University of Technology. From 1980 to 2009 he was an academic teacher and researcher with the Gdynia Maritime University, and since 2009 he has been with the Gdansk University of Technology, where he is currently...
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Model of management of knowledge bases in the information technology evaluation environment
PublicationThe paper presents the model of management of knowledge bases in multi-agent system for evaluation of information technologies (IT_MAS). Such system is being developed in Gdansk Uni-versity of Technology by Information Technology Management Team. Multi-agent system is supposed to support manager level specialists during decision processes when there is identified need to buy or change any information technology. The main goal of...
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DYNWIR S-70 program for modal analysis of multisupported and multimass rotors
PublicationThe article provides a brief description of the program Dynwir-S-70 (currently being developed in the Rotor Dynamics and Slide Bearings Department in the Institute of Fluid-Flow Machinery Polish Academy of Sciences in Gdansk) which is a program for analysis of multi-supported and multi-mass rotors. Used algorithms and the construction of mass and stiffness matrix were presented. Damping matrix structure based on Rayleigh damping...
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Influence of separation gap on the structural response of colliding structures under earthquake excitation
PublicationThe high level of urbanization in the XXIst century forces the designers to design closely-separated structures and to take into account many factors influencing their response during seismic excitation, which are the most unpredictable loads which can affect civil engineering structures. Interactions between insufficiently adjacent buildings, known as the earthquake-induced structural pounding, may cause serious damage to the structures,...
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Natural convection in symmetrically heated vertical channels
PublicationThe study describes natural convection through a vertical channel, open on four sides and bound by two isothermal walls. Both balancing and infrared experimental investigations were performed in air (Pr = 0.71) to estimate the impact of channel width s and wall-to-ambient temperature difference (tw - t∞) on natural convective heat transfer, the formation of air flow patterns and the rate of flow pattern formation. The study was...
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Separation and determination of the group-type composition of modern base and lubricating oils with a wide range of polarity, especially emitted to the environment
PublicationLubricating oils are composed of base oils (>85% v/v) and enriching additives (<15% v/v). Three types of base oils may be distinguished: 1) traditional bases (obtained by low-volatile fractions from crude oil distillation refining), 2) synthetic bases (mainly poly-alpha-olefins, sometimes esters, especially succinic acid esters), 3) bases of natural origin (especially obtained from refined plant oils). The bases of natural origin...
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Results of the effect of mixtures of ketoprofen with three cations on the germination of Sorghum bicolor (sorghum) seeds
Open Research DataThe research data includes an attempt to verify whether the addition of cations (sodium, ammonium and potassium) at levels found in the environment would affect the toxicity of pharmaceuticals to Sorghum Bicolor grain. Ion concentrations were selected based on studies of water samples collected in water bodies receiving wastewater from wastewater treatment...
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Results of the effect of mixtures of ketoprofen with three anions on the germination of Sorghum bicolor (sorghum) seeds
Open Research DataThe research data includes an attempt to verify whether the addition of anions (bromide, chloride and fluoride) at levels found in the environment would affect the toxicity of pharmaceuticals to Sorghum Bicolor grain. Ion concentrations were selected based on studies of water samples collected in water bodies receiving wastewater from wastewater treatment...
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Test of the antimicrobial properties against E. coli of the innovative CS-2b preservative.
Open Research DataThe dataset contains the results of a single series of determinations of the antimicrobial properties against E. coli of the innovative CS-2 b preservative in the solution of model fluids.During the test, the infected product is inoculated (on chromogenic Coliform Agar) at specified intervals (0 min. [cs2b 0] and after 1 day-24 h of incubation [cs2b...
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Test of the antimicrobial properties against Listeria monocytogenes of the innovative CS-2a preservative.
Open Research DataThe dataset contains the results of a single series of determinations of the antimicrobial properties against Listeria monocytogenes of the innovative CS-2 a preservative in the solution of model fluids.During the test, the infected product is inoculated (on Oxford Agar) at specified intervals (0 min. [Listeria cs2a 0] and after 1 day-24 h of incubation...
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Evaluation of antimicrobial properties of thermomelt adhesives modified with zinc compounds
Open Research DataThe dataset contains the results of microbiological tests of thermomelt adhesives modified with zinc compounds, whose activity was assessed for their ability to reduce the number of Escherichia coli and Staphylococcus aureus strain, representing the Gram (-) and Gram (+) bacteria, respectively. The evaluation of antimicrobial properties of samples were...
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Comparative Greenness Evaluation
PublicationGreenness of analytical procedure is multivariable aspect as many greenness criteria should be taken into consideration. On the other hand, modern analytical chemistry offers dozens of analytical procedures, based on different sample preparation and final determination techniques that are used for the determination of a given analyte in a given matrix. For such complex decision-making processes, multi-criteria decision analysis...
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Some Aspects of Designing Nozzle Segments of Axial Microturbines,
PublicationIn the paper a multi-stage micro-turbine with partial admission of all the stages is described in detail and the results of the numerical calculations and experimental investigations are presented, followed by an appropriate discussion and conclusions.
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Pumping effect measured by PIV method in a multilayer spike electrode EHD device for air cleaning
PublicationDust particles can be harmful for human health when inhaled. Particularly dangerous are submicrometer dust particles, which can contain traces of toxic elements and can easily penetrate into the human respiratory system. Thus, efficient devices for the air cleaning from submicrometer dust particles are needed. Recently, Katatani and Mizuno have proposed an electrohydrody- namic (EHD) device for air cleaning for submicrometer particles....
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Buckling Analysis of a Micro Composite Plate with Nano Coating Based on the Modified Couple Stress Theory
PublicationThe present study investigates the buckling of a thick sandwich plate under the biaxial non-uniform compression using the modified couple stress theory with various boundary conditions. For this purpose, the top and bottom faces are orthotropic graphene sheets and for the central core the isotropic soft materials are investigated. The simplified first order shear deformation theory (S-FSDT) is employed and the governing differential...
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Preload monitoring in a bolted joint using Lamb wave energy
PublicationThe knowledge of the load in prestressed bolted connections is essential for the proper operation and safety of engineering structures. Recently, bolted joints have become an area of intensive research associated with non-destructive diagnostics, in particular in the context of wave propagation techniques. In this paper, a novel procedure of bolt load estimation based on the energy of Lamb wave signals was proposed. Experimental...
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Data obtained by computation for X-ray focusing using oriented Gaussian beams
Open Research DataThe propagation of X-ray waves through an optical system consisting of several X-ray refractive lenses is considered. Gaussian beams are exact solutions of the paraxial equation. The Helmholtz equation describes the propagation of a monochromatic electromagnetic wave. Since the widths of the beams are much larger than the wavelength of X-rays, Gaussian...
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Facile synthesis and characterization of graphene and N-doped graphene by CVD method from liquid precursors for promising electrode materials
PublicationIn this study, high-quality and few-layered graphene was synthesized using the chemical vapor deposition (CVD) method from liquid sources. Two different liquid carbon sources, pyridine, and benzene, were used and deposited on nickel foam under heat conditions using a bubbler in a quartz tube. X-ray diffraction (XRD) and Raman analysis confirmed the crystalline properties of graphene and N-doped graphene, demonstrating the high...
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Dispersive Micro‐Solid Phase Extraction of Selected Metals in Water and Food Samples Followed by ICP‐OES Analysis: Method Development, Analysis of Real Samples and Greenness Evaluation
PublicationMultiwalled carbon nanotubes (MWCNTs) are well-known adsorbents because of their high surface area, layered and hollow architecture, hydrophobicity, and multiple and easily accessible adsorption sites. In this study, MWCNTs were used for dispersive micro-solid-phase extraction of various metal chelates in environmental and food samples. Different parameters such as concentration of the chelating reagent, the sorbent dosage, the...
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Resilience of 5G Mobile Communication Systems to Massive Disruptions
PublicationThis chapter discusses vital techniques to enhance the resilience of 5G systems. It starts with dependability assessment of 5G networks. Next, it describes (a) the frequency fallback technique to improve availability and survivability of 5G services, (b) segment interleaving scheme to enhance communications resilience between base stations and the remaining part of the network and (c) multi-operator protection to address the resilience...
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Computer controlled systems - 2022/2023
e-Learning Coursesmateriały wspierające wykład na studiach II stopnia na kierunku ACR pod tytułem komputerowe systemy automatyki 1. Computer system – controlled plant interfacing technique; simple interfacing and with both side acknowledgement; ideas, algorithms, acknowledge passing. 2. Methods of acknowledgement passing: software checking and passing, using interrupt techniques, using readiness checking (ready – wait lines). The best solution...
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CCS-lecture-2023-2024
e-Learning Coursesmateriały wspierające wykład na studiach II stopnia na kierunku ACR pod tytułem komputerowe systemy automatyki 1. Computer system – controlled plant interfacing technique; simple interfacing and with both side acknowledgement; ideas, algorithms, acknowledge passing. 2. Methods of acknowledgement passing: software checking and passing, using interrupt techniques, using readiness checking (ready – wait lines). The best solution optimization...
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Wielokryterialne Wspomaganie decyzji środowiskowych przy wydobywaniu węglowodorów z formacji łupkowych
PublicationPoszukiwanie i eksploatacja gazu z formacji łupkowych wymaga zidentyfikowania i uwzględnienia wielu czynników i uwarunkowań geologiczno-górniczych, ekonomiczno-finansowych, prawnych oraz szeroko rozumianych aspektów przestrzenno-środowiskowych. Poruszane zagadnienia prowadzą do zidentyfikowania problemów decyzyjnych, które mogą pojawiać się przy eksploatacji gazu z łupków, a które wiążą się z intensywnym korzystaniem z zasobów...
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BIODIVERSITY OF YEASTS ISOLATED FROM CAVES OF THE POLISH TATRA MOUNTAINS, AND ITS BIOTECHNOLOGICAL POTENTIAL
PublicationMost of the Earth’s biosphere is permanently or periodically exposed to temperatures below 5°C. Cold habitats harbor a wide diversity of psychrophiles. For many years Antarctica has been the geographic area preferred for studying the diversity and properties of cold-adapted microorganisms. However, the non-Antarctic habitats like Himalayas or Alps are also extensively explored. The Tatra Mountains are Europe’s second-highest massif...
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The effect of pH change of ketoprofen solutions on the germination of Sorghum bicolor (sorghum) seeds
Open Research DataIn these studies, an attempt was also made to determine whether (and, if so, to what extent) the change in pH affects the toxicity of ketoprofen will affect the germination of Sorghum bicolor (sorghum) seeds. As reported by Kudlak B, Wieczerzak M, Yotova G, Tsakovski S, Simeonov V, Namieśnik J (2016) Environmental risk assessment of Polish wastewater...
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Wpływ zastosowania nakładek wzmacniających środnik na nośność i sztywność doczołowego węzła śrubowego.
PublicationCiągłe dążenie do upraszczania elementów konstrukcyjnych oraz znajdowania mniej czasochłonnych rozwiązań wykonawczo – montażowych wraz z nieuchronnym wzrostem kosztów robocizny determinują m.in. eliminację z procesów technologicznych tych etapów, które nie podlegają automatyzacji. Taką czynnością jest przede wszystkim spawanie dodatkowych wzmocnień i usztywnień węzłów w postaci żeber. Efektem wieloletnich badań jest metoda przedstawiona...
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Client-side versus server-side geographic data processing performance comparison: Data and code
PublicationThe data and code presented in this article are related to the research article entitled “Analysis of Server-side and Client-side Web-GIS data processing methods on the example of JTS and JSTS using open data from OSM and Geoportal” (Kulawiak et al., 2019). The provided 12 datasets include multi-point and multi-polygon data of different scales and volumes, representing real-world geographic features. The datasets cover the area...
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Data obtained by computation for X-ray imaging of grating without magnification using oriented Gaussian beams
Open Research DataThe propagation of X-ray waves through an optical system consisting of grating and X-ray refractive lenses is considered. In this approach, the propagating wave is represented as a superposition of the oriented Gaussian beams. The direction of wave propagation in each Gaussian beam is consistent with the local propagation direction of the X-ray wavefront.
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Data obtained by computation for X-ray imaging of grating with magnification factor equal 2 using oriented Gaussian beams
Open Research DataThe propagation of X-ray waves through an optical system consisting of grating and X-ray refractive lenses is considered. In this approach, the propagating wave is represented as a superposition of the oriented Gaussian beams. The direction of wave propagation in each Gaussian beam is consistent with the local propagation direction of the X-ray wavefront.
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Data obtained by computation for X-ray imaging of grating with magnification factor equal 4 using oriented Gaussian beams
Open Research DataThe propagation of X-ray waves through an optical system consisting of grating and X-ray refractive lenses is considered. In this approach, the propagating wave is represented as a superposition of the oriented Gaussian beams. The direction of wave propagation in each Gaussian beam is consistent with the local propagation direction of the X-ray wavefront.
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Data obtained by computation for X-ray imaging of grating with magnification factor equal 8 using oriented Gaussian beams
Open Research DataThe propagation of X-ray waves through an optical system consisting of grating and X-ray refractive lenses is considered. In this approach, the propagating wave is represented as a superposition of the oriented Gaussian beams. The direction of wave propagation in each Gaussian beam is consistent with the local propagation direction of the X-ray wavefront.
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Effect of microstructure on mechanical properties and corrosion resistance of 2205 duplex stainless steel
PublicationThis paper presents results of the research on impact of microstructure of austenitic-ferritic steel of duplex type on its mechanical properties and susceptibility to stress corrosion cracking. As showed, improper processing technologies more and more often used in shipbuilding industry for plates and other half-finished products made of duplex steel may cause significant lowering their properties, which frequently makes their...
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Detection of debonding in adhesive joints using Lamb wave propagation
PublicationAdhesively bonded joints are widely used in many branches of industry. Mechanical degradation of this type of connections does not have significant symptoms that can be noticed during visual assessment, so non-destructive testing becomes a very important issue. The paper deals with experimental investigations of adhesively bonded steel plates with different defects. Five samples (an intact one and four with damages in the form...
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Monitoring Steel Bolted Joints during a Monotonic Tensile Test Using Linear and Nonlinear Lamb Wave Methods: A Feasibility Study
PublicationThe structural integrity of steel bolted joints may be compromised due to excessive loading. Therefore, condition assessment and the detection of potential defects before they cause a failure have become a major issue. The paper is focused on the condition monitoring of a bolted lap joint subjected to progressive degradation in a tensile test. The inspection used Lamb waves propagated through the overlap area. Wave propagation...
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Lamb wave-based monitoring of shear failure of an adhesive lap joint
PublicationThe paper presents a study on the elastic wave propagation in adhesive joints of steel plates subjected to tensile loading. A single lap joint was chosen for analysis because of its simplicity and plurality of applications. Experimental investigations consisted of the uniaxial extension of prepared specimens. Force and displacement values were recorded by a testing machine. Simultaneously, guided Lamb waves were excited and signals...
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Photogrammetry image-based approach for imperfect structure modelling and FE analysis
PublicationThis study aims to model and analyse imperfect tructures using real measurements, employing photogrammetry technique commonly used in the geodesy. The study highlights the capability of the photogrammetry in aiding the structural analysis of imperfect engineering objects. Firstly, the photogrammetry measurements of a stiffened plate are carried out using a specially designed for the purpose experimental stand. Then, the plate surface...
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The use of thin diamond films in fiber optic low-coherence interferometers”
PublicationIn this paper we present the use of thin diamond films in fiber-optic low-coherence interferometers. Two kinds of diamond surfaces were used: undoped diamond film and boron-doped diamond film. They were deposited on glass plates as well as silicon layers. A conventionally used mirror was used as a reference layer. Diamond films were deposited using Microwave Plasma Enhanced Chemical Vapour Deposition (μPE CVD) system. Measurements...
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Numerical Study of Concrete Mesostructure Effect on Lamb Wave Propagation
PublicationThe article presents the results of the numerical investigation of Lamb wave propagation in concrete plates while taking into account the complex concrete mesostructure. Several concrete models with randomly distributed aggregates were generated with the use of the Monte Carlo method. The influence of aggregate ratio and particle size on dispersion curves representing Lamb wave modes was analyzed. The results obtained for heterogeneous...
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Novel two-step synthesis method of thin film heterojunction of BiOBr/Bi2WO6 with improved visible-light-driven photocatalytic activity
PublicationA novel two-step ionic liquid assisted procedure was applied for a controllable synthesis of BiOBr/Bi2WO6 heterojunction thin films. The preparation route involved an anodic oxidation of tungsten foil and hydrothermal transformation of as-anodized oxide in the presence of bismuth precursor and ionic liquid, N-butylpyridinium bromide [BPy][Br]. The BiOBr plates with irregular shapes adhered to the surface of flower-like Bi2WO6 and...
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Conception of interactive information and decision support system - model and evaluation
PublicationThis article presents conception of interactive information and decision support system for urban and industrial air quality management. The emphasis of the project is on real-time analysis and multi-media information, and support of distributed and mobile clients through the Internet.
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Design space reduction and variable-fidelity EM simulations for feasible Pareto optimization of antennas
PublicationA computationally efficient procedure for multi-objective optimization of antenna structures is presented. In our approach, a response surface approximation (RSA) model created from sampled coarse-discretization EM antenna simulations is utilized to yield an initial set of Pareto-optimal designs using a multi-objective evolutionary algorithm. The final Pareto front representation for the high-fidelity model is obtained using surrogate-based...
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Positron-electron correlation-polarization potentials for the calculation of positron collisions with atoms and molecules
PublicationWe present correlation-polarization potentials for the calculation of scattering cross sections of positrons with atoms and molecules. The potentials are constructed from a short-range correlation term and a long-range polarization term. For the short-range correlation term we present four different potentials that are derived from multi-component density functionals. For the long-range polarization term we employ a multi-term...
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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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Corrigendum to “An investigation on residual stress and fatigue life assessment of T-shape welded joints” [Eng. Fail. Anal. 141 (2022) 106685]
PublicationThis paper aims to quantitatively evaluate the residual stress and fatigue life of T-type welded joints with a multi-pass weld in different direction. The main research objectives of the experimental test were to test the residual stress by changing direction along with multiple wielding passes and determine the fatigue life of the welded joints. The result shows that compressive residual stress increases in the sample gradually...