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Search results for: PHOTOVOLTAIC ROOF TILE, BUILDING-INTEGRATED PHOTOVOLTAIC/THERMAL (BIPV/T), EXPERIMENTAL STUDY, NUMERICAL SIMULATIONS, ENERGY ANALYSIS
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The role of numerical tests in assessing road restraint system functionality
PublicationKey to understanding the needs and building road infrastructure management tools to prevent and mitigate run-off-road accidents is to identify hazards and their sources which are a result of wrong design, construction, and installation of road restraint systems. Building such tools requires advanced studies with field tests, simulations and models to demonstrate the effects of selected parameters on road user safety. The research...
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Super-resolved Thermal Imagery for High-accuracy Facial Areas Detection and Analysis
PublicationIn this study, we evaluate various Convolutional Neural Networks based Super-Resolution (SR) models to improve facial areas detection in thermal images. In particular, we analyze the influence of selected spatiotemporal properties of thermal image sequences on detection accuracy. For this purpose, a thermal face database was acquired for 40 volunteers. Contrary to most of existing thermal databases of faces, we publish our dataset...
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Advanced Experimental and Numerical Analysis of Behavior Structural Materials Including Dynamic Conditions of Fracture for Needs of Designing Protective Structures
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A study of the electronic states of pyrimidine by electron energy loss spectroscopy
PublicationThe electron energy loss spectra were measured in pyrimidine at the constant electron residual energy varied from 15 meV to 10 eV and in the scattering angle range 0–180°. The spectra were analysed applying an iteration fitting procedure to resolve the energy loss bands corresponding to excitation of the electronic states of pyrimidine. The vertical excitation energies of the singlet states of pyrimidine and of a number of the...
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Selection of material for X-ray tomography analysis and DEM simulations: comparison between granular materials of biological and non-biological origins
PublicationPhysical properties and X-ray tomography images of five different granular materials: glass bead, glass grit, short grain white rice, sorghum and clay granules (Seramis) are investigated to select the most promising materials for numerical simulations and time-lapse X-ray tomography imaging. The examined materials represent granular materials of non-biological origin (glass bead, glass grit and Seramis) and granular plant materials...
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The impact of footing conditions of a vertical-axis floating-roof tank on structural shell deformation
PublicationStructural shells of fuel tanks are often subjected to geometric imperfections which may lead to exceeding the ultimate and serviceability limit states. One of the means triggering shell deformation is non-uniform settlement caused by incoherent soil conditions. Analysis carried out in the work concerns of vertical-axis, floating-roof cylindrical shell which volume is 50.000 m3, founded on a complex multi-layered soil. The sensitivity...
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Wind resource assessment and energy yield prediction for the small wind turbine on the Szubieniczne Hill
PublicationThe goal of this study is to preliminary assess the wind resources on the Szubieniczne Hill in order to predict the annual energy production for planned small wind turbine. The analyzed site is located close to the Gdańsk University of Technology campus, in complex urban environment additionally surrendered by forested hills. The assessment is based on Computational Fluid Dynamics simulations which allow to evaluate the wind energy potential...
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Analysis of an Energy Management System of a Small Plant Connected to the Rural Power System
PublicationThis paper presents the analysis of an energy management system (EMS) implemented to fulfill the requirements of a microgrid (MG) power supply owned by a small industrial company and connected to the rural power system. The main goal of this system is to ensure connection with the existing rural power system in terms of energy exchange, as well as to perform islanding mode operation of the microgrid based on the energy demand of...
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Tensile failure study of 3D printed PLA using DIC technique and FEM analysis
PublicationThe paper presents the experimental and numerical study of the failure behaviour of Fused Filament Fabricated (FFF) Polylactic Acid (PLA) samples subjected to tensile load. The examined samples are printed in flat orientation with 0◦, 45◦ and 90◦ raster angles. During the experiments the deformation of the specimens is continuously scanned with the 3D Aramis measuring system utilizing the digital imaging correlation technique,...
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The experimental and numerical investigation of fracture behaviour in PMMA notched specimens under biaxial loading conditions – Tension with torsion
PublicationThis paper presents the results of experimental fracture test of flat PMMA specimens under biaxial loading condition tension with torsion (proportional). The specimens were made in two thicknesses: 5 and 15 mm and were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. Thanks to the ARAMIS 3D 4 M non-contact vision system, measurement of the elongation and twist angle were recorded. During experimental...
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A study on microcrack monitoring in concrete: discrete element method simulations of acoustic emission for non-destructive diagnostics
PublicationThe research is focused on the monitoring of fracture evolution in concrete beams under three-point bending using the acoustic emission technique and the discrete element method. The main objective of the study was to numerically and experimentally investigate the mechanism behind the generation of elastic waves during acoustic emission events and their interaction with micro- and macro-cracking in concrete beams under monotonic...
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Structural response of existing spatial truss roof construction based on Cosserat rod theory
PublicationPaper presents the application of the Cosserat rod theory and newly developed associated finite elements code as the tools that support in the expert-designing engineering practice. Mechanical principles of the 3D spatially curved rods, dynamics (statics) laws, principle of virtual work are discussed. Corresponding FEM approach with interpolation and accumulation techniques of state variables are shown that enable the formulation...
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Some Optimization Methods for Simulations in Volunteer and Grid Systems
PublicationIn this chapter, some optimization methods have been presented for improving performance of simulations in the volunteer and grid computing system called Comcute. Some issues related to the cloud computing can be solved by presented approaches as well as the Comcute platform can be used to simulate execution of expensive and energy consuming long-term tasks in the cloud environment. In particular, evolutionary algorithms as well...
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Behaviour of deformed steel columns exposed to impact load during earthquakes: numerical analysis
PublicationIt has been observed during earthquakes that the so called soft-storey failure of an upper floor of a building leads to considerable vertical impact load acting on structural members of the lower storeys. The aim of this paper is to investigate numerically the behaviour of horizontally deformed columns (deformation as the result of earthquake loading) that are additionally subjected to vertical impact load. In the first stage of...
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Shaking table experimental study on the effectiveness of polymer bearings for seismic isolation of structures
PublicationSeismic isolation has been recognised to be a very effective way of protecting structures from damage during earthquakes. It allows us to extend the natural period of the structure and therefore avoid resonance with the ground motion. Moreover, by increasing damping in the isolation devices, more energy can be dissipated and thus the structural response can be further reduced. The aim of this paper is to show the results of the...
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Application of the DSC analysis of thermoplastic polyurethane elastomers to a comparative study of their technological properties
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Techno-economic evaluation of combined cycle gas turbine and a diabatic compressed air energy storage integration concept
PublicationMore and more operational flexibility is required from conventional power plants due to the increasing share of weather-dependent renewable energy sources (RES) generation in the power system. One way to increase power plant’s flexibility is integrating it with energy storage. The energy storage facility can be used to minimize ramping or shutdowns and therefore should lower overall generating costs and CO2 emissions. In this article,...
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Thermal visualization of Ostwald-de Waele liquid in wavy trapezoidal cavity: Effect of undulation and amplitude
PublicationThe present study is concerned with the numerical simulations of Ostwald-de Waele fluid flow in a wavy trapezoidal cavity in the presence of a heated cylinder situated at the center of the cavity. The work consists in characterizing the mixed convection as a function of the intensity of heat flow. The flow behaviour and temperature distribution in a cavity are the main focus of this study. The lower wall of the cavity is fixed...
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Ukrainian Market of Electrical Energy: Reforming, Financing, Innovative Investment, Efficiency Analysis, and Audit
PublicationThe aim of this research is to determine the influence of electrical energy market regulation reform in Ukraine on the competitive environment, the reproduction processes of financial and innovative support, and the energy efficiency of the national economy. The authors have put forward and verified the hypothesis that, under conditions of institutional maturity of the Ukrainian electrical energy market, its liberalization and...
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Possibilities and benefits of a new method of modifying conventional building materials with phase-change materials (PCMs)
PublicationThe paper presents a current study devoted to the optimization of the amount of PCM present within traditional building materials, utilized in this case in hollow-brick walls. Authors focus on proposing an alternative to typical direct addition of PCM to existing building materials: introducing two- and three-component mixtures, based on a porous PCM carrier, which in this case was construction aggregate. Preliminary studies of...
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Towards an efficient multi-stage Riemann solver for nuclear physics simulations
PublicationRelativistic numerical hydrodynamics is an important tool in high energy nuclear science. However, such simulations are extremely demanding in terms of computing power. This paper focuses on improving the speed of solving the Riemann problem with the MUSTA-FORCE algorithm by employing the CUDA parallel programming model. We also propose a new approach to 3D finite difference algorithms, which employ a GPU that uses surface memory....
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Thermal failure of a second rotor stage in heavy duty gas turbine
PublicationThe impulse mode of operation and the supply of various types of fuels causes frequent failures even in the heavy duty gas turbines. The paper presents the ravages of second rotor stage failure in a gas turbine. The excessive thermal elongation rise caused by fuel change was indicated as the main cause. We applied nonlinear numerical analysis, preceded by thermodynamic calculations of the turbine and visual inspection of the effects...
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Topological-numerical analysis of a two-dimensional discrete neuron model
PublicationWe conduct computer-assisted analysis of a two-dimensional model of a neuron introduced by Chialvo in 1995 [Chaos, Solitons Fractals 5, 461–479]. We apply the method of rigorous analysis of global dynamics based on a set-oriented topological approach, introduced by Arai et al. in 2009 [SIAM J. Appl. Dyn. Syst. 8, 757–789] and improved and expanded afterward. Additionally, we introduce a new algorithm to analyze the return times...
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Experimental and numerical studies of double corrugated steel arch panels
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Experimental and numerical identification of separation zones in the cent-rifugal compressor
PublicationW pracy przedstawiono analizę przepływu w obszarze koła wirnikowego oraz dyfuzora bezłopatkowego sprężarki powietrza. Wyniki obliczeń w ramach modelu 3D (FLUENT 5.5) porównano z wynikami badań laboratoryjnych na stanowisku sprężarkowym Katedry Sprężarek w Sankt Petersburgu. Celem porównania jest ocena możliwości identyfikacji stref przepływu z oderwaniem, w ramach modeli dostępnych w wykorzystanym programie obliczeniowym. W wyniku...
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Numerical simulations of the influence of injection moulding parameters on mechanical properties of the polyamide composite
PublicationZaprezentowano wyniki symulacji numerycznej wpływu parametrów technologicznych procesu wtryskiwania na wybrane właściwości mechaniczne kompozytu poliamidowego. Symulacje przeprowadzono z wykorzystaniem programu Cadmould-3d.
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Numerical Simulations of DDT Limits in Hydrogen-Air Mixtures in Obstacle Laden Channel
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Numerical simulations of transverse pounding-involved response of buildings due to earthquake excitation.
PublicationCelem artykułu jest analiza (w kierunku poprzecznym) zachowania się uderzających o siebie budynków podczas trzęsienia ziemi. W analizie tej obie konstrukcje modelowane są przy użyciu dyskretnego, sprężysto-plastycznego modelu o skupionych masach, zaś do symulacji zderzeń zastosowano nieliniowy model lepko-sprężysty. Wyniki analizy pokazują, iż zderzanie prowadzi do znacznego wzrostu odpowiedzi w kierunku poprzecznym dla konstrukcji...
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Extremal thermal loading of a bifurcation pipe
PublicationThe subject of considerations is a spherical bifurcation pipe of a live steam made of steel P91, which is an element of a block of coal-fired power plant working with a 18K370 turbine. As experience shows, it is a very sensitive element of the boiler pipelines. An extreme work scenario for such a block has been adopted, in which the turbine is shutting down to a warm state three times in 24 hours. This is an action dictated by...
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Numerical Model of Surface and Quasi-Spherical Sea Noise and Its Application to Analysis of DIFAR Systems
PublicationVarious types of passive sonar systems are used to detect submarines. These activities are complex and demanding. Therefore, computer simulations are most often used at the design stage of these systems. For this reason, it is also necessary to simulate the acoustic ambient noise of the sea. The article proposes a new numerical model of surface and quasi-spherical sea noise and presents its statistical parameters. The results of...
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Unique agreement of experimental and computational infrared spectroscopy: a case study of lithium bromide solvation in an important electrochemical solvent
PublicationInfrared (IR) spectroscopy is a widely used and invaluable tool in the studies of solvation phenomena in electrolyte solutions. Using state-of-the-art chemometric analysis of a spectral series measured in a concentration-dependent manner, the spectrum of the solute-affected solvent can be extracted, providing a detailed view of the structural and energetic states of the solvent molecules influenced by the solute. Concurrently,...
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Building Knowledge for the Purpose of Lip Speech Identification
PublicationConsecutive stages of building knowledge for automatic lip speech identification are shown in this study. The main objective is to prepare audio-visual material for phonetic analysis and transcription. First, approximately 260 sentences of natural English were prepared taking into account the frequencies of occurrence of all English phonemes. Five native speakers from different countries read the selected sentences in front of...
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Numerical analysis of CO2-water separation in a horizontal double T-junction
PublicationCarbon dioxide is considered one of the main factors leading to global warming. Considering the significant impacts of CO2 on climate change, various technologies have been developed in recent decades to control carbon emission, such as for example CO2 capture and storage. The developed cycle of a negative CO2 emission power plant includes some devices, out of which, separator plays an indispensable role. To this end, T-junction...
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Role of MnO in manganese–borate binary glass systems: a study on structure and thermal properties
PublicationStructural and thermal properties of x MnO−(100−x)B2O3 (where x=40, 50 and 60 mol%) glass samples have been investigated with the employment of various techniques. Fourier transform infrared spectroscopy results revealed the influence of MnO on glass matrix. Decrease of B–O bond-related band intensities has been observed. MnO addition was found to introduce broken [BO2O−]n chains. Differential scanning calorimetry (DSC) measurements...
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Monte Carlo simulations of the fracture resistance of an asphalt pavement layer
PublicationThe purpose of the proposed numerical model is to analyze the cracking of the wearing course in a pavement overlay, assuming a pre-existing crack that passes through the binding layer and base. The computations employed the author's simulation-based Monte Carlo material model, which describes the failure process of a Semi-Circular Bend (SCB) specimen during standard laboratory testing of asphalt concrete. A key feature of this...
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Experimental study and comparison with predictive methods for flow boiling heat transfer coefficient of HFE7000
PublicationThis article describes an experimental study of flow boiling of HFE7000 inside a smooth vertical channel. The investigation has been carried out in a circular stainless-steel tube with an inner diameter of 2.3 mm. The data have been collected for the applied heat fluxes q ranging from 61 to 205 kW/m2, the mass flux G ranging from 214 to 1006 kg/(m2 s), the saturation temperature Tsat ranging from 30 to 54 °C and the full range...
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Squashed entanglement for multipartite states and entanglement measures based on the mixed convex roof
PublicationNew measures of multipartite entanglement are constructedbased on two definitions of multipartite information anddifferent methods of optimizing over extensions of the states. Oneis a generalization of the squashed entanglement where one takesthe mutual information of parties conditioned on the state's extensionand takes the infimum over such extensions. Additivity ofthe multipartite squashed entanglement is proved for both versionsof...
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An advanced Thermal-FSI approach to flow heating/cooling
PublicationActually, two-way thermal-energy exchange between working fluid and solid material of a casing is a leading problem for modern – semi automatic – design techniques. Many questions should be solved, especially, the turbulent mode of thermal energy transport both in fluid and solid, should be re-examined and reformulated from the primary principles. In the present paper, a group of researchers from Energy Conversion Department of...
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Wireless Charging Station Design for Electric Scooters: Case Study Analysis
PublicationThis study proposes an example of a wireless charging station design for a small-scale vehicle available on the market. The article analyzes basic transmitter inverter topologies and their compensation methods in terms of flexibility of control, tolerance to uncertainty in positioning, and the possibility of decreasing the integration price. Our comprehensive analysis focuses on the battery voltage range, energy capacity, cost,...
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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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Stability Assessment of Coastal Cliffs Incorporating Laser Scanning Technology and a Numerical Analysis
PublicationWe investigated the cli coast in Jastrzebia Gora, Poland. The measurements that were taken between 2014 and 2018 by applying terrestrial, mobile, and airborne laser scanning describe a huge geometric modification involving dislocations in a 2.5 m range. Dierential maps and a volumetric change analysis made it possible to identify the most deformed cli’s location. Part of the monitoring of coastal change involved the measurement...
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Evaluation of fire hazard in electrical installations due to unfavorable ambient thermal conditions
PublicationEvaluation of fire hazard caused by electrical installations is a difficult and important topic, and it limits the possibility of loss of life or health of people, as well as the occurrence of significant property damage. In particular, this hazard was caused by power cables and especially photovoltaic (PV) installations. The authors proved that power cables directly exposed to strong solar radiation are likely to exceed maximum...
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Effect of the inclination angle of the condenser on the heat transfer coefficient value – experimental study
PublicationWhen considering problem of the condensation of the refrigerant in a flow inside channel, one needs to pay attention to the shape of its cross-section, the hydraulic diameter, the channel length as well as the orientation of the channel axis in space (horizontal, vertical, inclined). This paper presents an experimental study concerning the effect of the inclination angle of the condenser with a single coil pipe on the heat transfer...
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A non-adiabatic wavepacket dynamical study of the low energy chargetransfer process in the S3+ + H collision
PublicationThe collisional system S3+ + H?S2+ + H+ has been studied using a time-dependent wavepacket methodologyin two-dimensions. Using available potential energy surfaces and coupling matrix elementsobtained from multireference ab initio calculations, five non-adiabatically coupled electronic states of1P symmetry have been included in the dynamical simulations. The collision has been studied in thelow energy regime of 1-10 eV. The wavepacket...
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Fractional neutron point kinetics equations for nuclear reactor dynamics – Numerical solution investigations
PublicationThis paper presents results concerning numerical solutions to a fractional neutron point kinetics model for a nuclear reactor. The paper discusses and expands on results presented in (Espinosa-Paredes et al., 2011). The fractional neutron point kinetics model with six groups of delayed neutron precursors was developed and a numerical solution using the Edwards’ method was proposed (Edwards et al., 2002). The mathematical model...
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The elasto-plastic numerical study of crack initiation in notched PMMA specimens under uniaxial loading conditions – Tension and torsion
PublicationThis paper presents the results of FEM numerical calculations aimed at describing the plastic strain and stress fields under critical loading conditions: tensile force or torsional moment. The calculations were carried out with reference to the results of experimental tensile and torsional tests of flat PMMA specimens weakened with V-notches of different root radii: 0.5, 2 and 10 mm. The procedure for conducting nonlinear numerical...
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COMPARATIVE NUMERICAL ANALYSIS OF DIFFERENT STRENGTHENING SYSTEMS OF HISTORICAL BRICK ARCHES
PublicationThe article presents a comparative numerical analysis of various ways to strengthen historical brick arches. Five ways of strengthening brick arches with steel tie-rods have been proposed. Two of these involve the use of braces wrapped around pillars supporting the arch connected with a tie-rod; another two ways involve the use of the tie-rods with welded metal sheets of different sizes; the last way involves the use of the tie-rod...
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The electronic excited states of dichloromethane in the 5.8-10.8 eV energy range investigated by experimental and theoretical methods
PublicationWe present a comprehensive experimental high-resolution vacuum ultraviolet (VUV) photoabsorption spectrum of dichloromethane, CH 2 Cl 2 , with absolute cross sections determined for the full 5.8–10.8 eV energy-range. The calculations on the vertical excitation energies and oscillator strengths were performed using the equation-of-motion coupled cluster method, restricted to the single and double excitations level (EOM-CCSD), and...
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EXPERIMENTAL AND NUMERICAL INVESTIGATION ON SPECIMEN GEOMETRY EFFECT ON THE CTOD VALUE FOR VL-E36 SHIPBUILDING STEEL
PublicationThere are special cases in the marine industry, where additional material tests, such as the fracture toughness test, must be performed. Additional fracture toughness tests, such as CTOD (Crack Tip Opening Displacement), are typically performed on three-point bend specimens. The dimension that defines all the specimen dimensions is the thickness of the material to be tested. It is recommended by classification societies (e.g. DNVGL)...
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The impact of initial and boundary conditions on severe weather event simulations using a high-resolution WRF model. Case study of the derecho event in Poland on 11 August 2017
PublicationPrecise simulations of severe weather events are a challenge in the era of changing climate. By performing simulations correctly and accurately, these phenomena can be studied and better understood. In this paper, we have verified how different initial and boundary conditions affect the quality of simulations performed using the Weather Research and Forecasting Model (WRF). For our analysis, we chose...