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EN
The research described in this paper aims to enhance the structural health monitoring (SHM) of highway bridges by integrating numerical simulations with experimental data. A simply supported highway bridge is studied under traffic loads, and both numerical and experimental approaches were employed. The numerical model of the bridge was developed using ANSYS, while high-resolution experimental data were collected from velocity transducers placed at key points on the bridge. The experimental data were compared with the results from the numerical model for validation. The results showed that the natural frequencies obtained from both the experimental and numerical analyses were closely aligned, demonstrating the reliability of the model. The validated model was further used to predict long-term structural behaviours under different operational conditions, contributing to better maintenance planning and the sustainability of infrastructure. The study concludes that combining numerical simulations with experimental data improves the accuracy of SHM, enabling early detection of potential structural issues and extending the lifespan of bridges. Key findings emphasize the significant role of vehicle speed in influencing the dynamic response of the bridge, as well as the importance of considering material properties and vehicle loads in predicting structural health.
PL
Badania opisane w niniejszym artykule mają na celu poprawę monitorowania stanu konstrukcji (structural health monitoring – SHM) mostów na autostradach poprzez integrację symulacji numerycznych z danymi eksperymentalnymi. Prosto podparty most na autostradzie jest badany pod obciążeniem ruchem drogowym i zastosowano zarówno podejście numeryczne, jak i eksperymentalne. Model numeryczny mostu został opracowany przy użyciu programu ANSYS, podczas gdy dane eksperymentalne o wysokiej rozdzielczości zostały zebrane z przetworników prędkości umieszczonych w kluczowych punktach mostu. Dane eksperymentalne zostały porównane z wynikami modelu numerycznego w celu walidacji. Wyniki pokazały, że częstotliwości drgań własnych uzyskane zarówno z analiz eksperymentalnych, jak i numerycznych były ściśle dopasowane, co świadczy o niezawodności modelu. Zweryfikowany model został następnie wykorzystany do przewidywania długoterminowych zachowań strukturalnych w różnych warunkach operacyjnych, przyczyniając się do lepszego planowania konserwacji i zrównoważonego rozwoju infrastruktury. W badaniu stwierdzono, że połączenie symulacji numerycznych z danymi eksperymentalnymi poprawia dokładność SHM, umożliwiając wczesne wykrywanie potencjalnych problemów strukturalnych i wydłużając żywotność mostów. Kluczowe wyniki badań podkreślają istotną rolę prędkości pojazdu we wpływie na dynamiczną reakcję mostu, a także znaczenie uwzględnienia właściwości materiału i obciążeń pojazdu w przewidywaniu stanu konstrukcji.
EN
Using torch brazing techniques, 316 stainless steel was brazed to CP copper using flux-coated low silver content filler with 20% Ag. The brazing torch utilized a fuel mixture of propane gas with oxygen to produce the required heating amount due to the possibility of economic interest in employing low-silver-content filler. The brazing filler's braze ability with SUS304 and copper was scrutinized and deeply analyzed. A ferrite barrier layer was made on the stainless-steel side, and an excellent brazed joint was produced. Metallurgical studies using an optical microscope and a scanning electron microscope (SEM) confirmed the production of a ferrite layer. This layer's advantages were carefully examined with metallurgical testing, electron diffraction scanning (EDS), EDS mapping, and EDS line analyses, including preventing copper intergranular penetration into the stainless-steel grain boundary. The mechanical properties of the brazed joint and its usability were assessed through Vickers microhardness and tensile tests on the brazing seam and both base metals. The results of the brazing process showed that using flux-coated low-silver brazing techniques produced strong joints with satisfactory mechanical properties. These techniques are a cost-effective alternative to high-priced brazing fillers with high silver content. Geometrical models simulated the heat distribution using ANSYS and SOLIDWORKS software to analyze penetration depth, joint quality, surface cracks, and the relation between molten filler density variation and the wetting process.
EN
The aim of the research was to analyse the possibilities of a model description of the type of bone fracture, the state of stress and strain, the method of fix and load, and the physical properties of bone tissue in relation to the method of loading the hip joint in individual phases of physical activity. Design/methodology/approach Analysis of the phenomenon of bone fracture with the use of the finite element method (FEM), which allows to observe the phenomenon of bone fracture affected by osteoporosis, taking into consideration bone disease foci. Modelling of femoral fracture propagation at different periosteal densities was performed. Findings Differences in the method of fracture of the femoral neck are presented, showing different boundaries of bone discontinuity depending on the point of fracture initiation and the force required for its propagation. Research limitations/implications Reproduction of the diseased bone may be limited by the accuracy of its digital model and the physically limited density of the FEM mesh. Using model tests allows us to understand the phenomenon of osteoporotic bone fracture and predict the effects of fracture, which will allow for faster implementation of an effective treatment method. Practical implications The use of the FEM method for analysis allows obtaining knowledge about the formation of bone discontinuities after fracture. It also allows for predicting the place of its occurrence and selecting the appropriate treatment method. Originality/value There was a significant difference in the shape of the femoral neck fracture depending on the place of its initiation. The effectiveness of the FEM analysis in predicting the location, shape and type of fracture is presented.
EN
Vibration control is very important for high-speed rotors. Oil film damping is considered an effective vibration-damping method, especially for long shafts in gas turbines, ships, and other high-speed rotating equipment. The existing groove in the internal surface of the tilt bearing increases the amount of oil that flows through the bearing; this is more effective in suppressing the vibration of the rotor system carried by the plain bearing. In order to suppress the vibration of the rotor system, which is supported by sliding bearings, a different groove-shaped oil flow (GSOF) is studied and analysed in this paper. A different shape of grooves in bearings was set up and measured to study the vibration-damping effect of the flow oil shape with GSOF. ANSYS software presents significant benefits to engage Fluent for oil flow with Transient structural for vibration measurements. This paper uses these terms to perform the simulation numerically to explore the groove-shaped damper's damping effect under the rotor system. The study identified three enhancements of vibration and settling time. First, the circular groove showed a 35.71% reduction in amplitude and 10% increase in stilling time; the next one is the circular groove which reduced the amplitude by 42.85% and the settling time by 0%. The third modification was the inclined groove which reduced the amplitude by 42.85% and the settling time by 12%. The last one was the triple-inclined groove, which reduced the amplitude and settling time by 57.14% and 20%, respectively.
EN
The most common gas-shielded arc welding method is tungsten inert gas welding, which uses shielding gas to isolate the welded area. Such technique is mostly used in the industrial domain, including steel framework fabrication and installation, plumbing systems, and other building jobs. The welding method and the implementation of a suitable welding joint based on some factors that contribute to the fusion process were studied in the present research. The research investigated the specifications and efficiency of the area to be welded in terms of the thermal effect on the welding joint shape and some significant mechanical property-related factors which that were determined during the welding process. In this paper, aluminum alloy sheets, AA 6061-T6, with a thickness of 3 mm, were used with a 60mm width and 80mm length. These sheets were prepared to be welded using welding currents of 90A, 95A, and 100A, welding speeds of 60mm/min, 80 mm/min, and100 mm/min, and gas flow rates of 8 l/min, 9 l/min, and 10 l/min. The experiments were designed at three distinct levels. These levels were selected to create the L9 orthogonal array. Regression analysis, signal-to-noise ratio evaluation, and analysis of variance were carried out. The created model has enhanced accuracy by predicting the reinforced hardness found in the weld specimens, according to the regression study, which showed R2= 90.09%. In addition, it was discovered that the ideal welding parameters for a welded specimen were 100 A for welding current, 80 mm/min for welding speed, and 9 l/min for gas flow. The present research examined the shape of the thermal distribution of welded parts using the engineering computer program ANSYS. The experimental results clarified the proposed approach, as they showed that the welding current is the most influential factor in the hardness of the weld using the fusion process of 90.95%, followed by the welding speed of 7.48%, while the gas flow rate of 1.52% has the least effect. The authors recommend using qualified welders to ensure optimal performance. It is anticipated that these findings will serve as a foundation for analysis to optimize welding processes and reduce welding defects.
6
Content available remote Problemy dotyczące modelowania obciążenia wiatrem obiektów budowlanych
PL
Im bardziej skomplikowany kształt obiektu budowlanego, tym trudniej prognozować, jak będą na niego oddziaływały masy powietrza podczas przepływu. Problem jest istotny z uwagi na niezawodność obiektów budowlanych. Analizy numeryczne oraz badania doświadczalne pozwolą w przyszłości zmodyfikować wytyczne normowe, przyczyniając się do poprawy bezpieczeństwa obiektów budowlanych.
EN
The more complex the shape of a building object, the more difficult it is to predict how air masses will affect it during flow. The problem is important for the reliability of buildings. Numerical analyses and experimental studies will allow future modification of the standard guidelines, contributing to the improvement of the safety of buildings.
EN
The work is devoted to the diagnostics of the stress state of systems that soften the shock load on the vehicle body, the elastic element of the car suspension such as a multi-leaf spring. The construction of a mathematical model taking into account the geometric nonlinearity according to the finite element method theory is considered. Mathematical modelling was carried out to take into account the change in the stiffness matrix of the system when changing its shape. For research, a symmetrical semi-elliptical spring consisting of five leaves is used. All numerous numerical experiments were performed in two computer-aided design (CAD) systems: ANSYS, a heavy multipurpose package and SolidWorks, a middle-level multipurpose package. Computeraided design algorithms have been developed to expand the capabilities of CAD. The analysis of the results obtained allows to conclude that the traditional models of nonlinearity in ANSYS and SolidWorks give approximately the same results, which at the maximum point differ by 20.6% from the data of a full-scale experiment. When using the proposed model, this difference is reduced to 7.95%.
EN
In the past few decades, natural fiber reinforced polymeric composites have gained significant importance for various structural applications in different sectors like the automotive, aerospace, sports and building construction industries. However, hybridizations make the composite more versatile in term of strength, weight and its processing for many engineering applications. In the current study, a polyester resin matrix was reinforced with two different natural fibers, namely kenaf and palmyra palm leaf stalk (PPLS) and hybridized with glass fiber. Four layers of two different fiber mats, kenaf/glass and PPLS/glass with different stacking sequences were employed to fabricated laminates by the hand lay-up technique. In this case, an attempt was made using the numerical approach to investigate the influence of glass fiber on the mechanical characteristics of the laminates. To substantiate the results of the numerical approach, experiments were conducted. Enhancement of both the tensile and flexural strength was observed due to hybridization of both the kenaf and PPLS fiber with glass fiber. The tensile and flexural strength improved by 68.91 and 37.63% respectively when the kenaf fiber was hybridized with glass fiber. Similarly, enhancement of 54.42% of the tensile strength and 15.92% of the flexural strength were noticed when the PPLS fiber was hybridized with glass fiber. Through the use of ANSYS software, finite element analysis (FEA) was employed as a simulation method to examine the tensile and flexural strength. The numerical findings were found to be quite close to the experimental results, with a variation of less than 3%.
EN
Purpose: The study of cracks behaviour in a composite plate is of significant importance in the dynamics of the Mechanical parts in order to avoid design failures due to resonance or high amplitude vibrations. Design/methodology/approach: In this paper, a square glass-epoxy composite plate is adopted. The plate has four layers with symmetric and asymmetric lamination. Assuming the cracks are profound as defects. The results were obtained by using a numerical solution of mechanical APDL from ANSYS. Findings: It has been found for different boundary conditions that the rank of natural frequencies is decreased by increasing the crack ratio due to the reduction of the plate’s stiffness, whereas the crack direction has no mentioned effect for a small angle of rotation. Research limitations/implications: The accuracy of results is verified by comparing a single case of the current work with other previous investigations. value: Evaluate the influence of the crack length ratio, angle of the crack rotation, boundary conditions and lamination angles on the natural frequencies of the square composite plate with glass-epoxy materials.
EN
Several modelling techniques are currently available to analyse the efficiency of inter-digital transducers (IDTs) fabricated on piezoelectric substrates for producing surface acoustic wave (SAW) devices. Impulse response method, equivalent circuit method, coupling of modes, transmission matrix method, and numerical techniques are some of the popular ones for this. Numerical techniques permit modelling to be carried out with any number of finger electrode pairs with required boundary conditions on any material of interest. In this work, we describe numerical modelling of SAW devices using ANSYS to analyse the effect of mass loading, a major secondary effect of IDTs on the performance of SAW devices. The electrode thickness of the IDT influences the resonance frequency of the SAW delay line. The analysis has been carried out for different electrode materials, aluminium, copper, and gold, for different substrate materials, barium titanate (BaTiO3), X-Y lithium niobate (LiNbO3), lithium tantalate (LiTaO3), and the naturally available quartz. The results are presented and discussed.
EN
During the operation of a rotor, various types of vibrations appear in this mechanical system and often limit the performance and endanger the safety of the operation. Therefore, dynamic analysis is essential because precise knowledge of the vibration behaviour is essential to ensure proper operation. This article presents a set of scientific techniques for the modelling and simulation of rotor vibrations. To work out the equations of the vibratory movement of the rotor, we used the energy approach of Lagrange. To achieve this, a model with one blading wheel carried by a shaft supported by two hydrodynamic bearings is chosen basedon the characteristics of the rotor studied (Fan 280 cement draft fan). It is an arduous task to manually ascertain the analytical resolution of the differential equations that characterise the vibratory behaviour of the rotor. The numerical approach employing the finite element method, programmed on the ANSYS software, made it possible to perform the vibration analysis of the rotor. First, the FAN 280 cement draft fan rotor is modelled using SolidWorks 3D software and reverse design using the coordinate measuring machine (CMM) for the design of the fins. Then, the modal characteristics of the fan rotor model were analysed using the finite element analysis (FEA) software ANSYS Workbench. Also, to study the effect of blade wear on critical speeds, the Campbell diagram was obtained. Finally, harmonic analysis was performed to determine the amplitude of the rotor vortex at critical speeds obtained with and without blade wear.
EN
Investigation on a designed and modified standard automatic transmission for a 2017 Yamaha Grizzly All-Terrain Vehicle was carried out to allow it to be controlled remotely and autonomously while maintaining its ability to be manually operated. The vehicle is a part of a project named AutoWeed. This project aims at developing a vehicle which can be used in the Australian outback to control and eradicate weeds. Preliminary tests were conducted on the vehicle to determine the performance parameters required to replace the movement supplied by the operator. Several devices used to achieve this motion were explored. It was concluded that the Motion Dynamics HB-DJ806 - LALI10010 electromechanical linear actuator be used as a proof of concept device for this application. This device is capable of exerting 200 N at 35 mm/seconds. It has a stroke length of 50 mm and was powered by a 12V DC motor, which drew 3 amps at maximum load. Through testing, it was found that the selected actuator did not have enough stroke length to cycle through the five gears on the ATV. This error was rectified allowing the system to function as intended. To achieve a reliable design, however, the Linak LA14 actuator was purchased as a final design as it was stronger, faster and had feedback capabilities. Before procurement, the new actuator was digitally modelled using SolidWorks 2017 and 3D printed to confirm the mounting position and method. An ANSYS FEA was conducted on all the custom-made components including the actuator bracket and mounting plate to ensure reliability. The bracket model was manufactured using 3D printing from ABS. It was recommended that for reliability, the bracket should be constructed from a stronger material such as aluminium. The results gained from testing proved that the autonomous transmission system implemented was reliable and repeatable. This was justified as the system achieved a 100% success rate when cycling through gears.
13
PL
Przedstawiono problem analizy złożonych konstrukcji stalowych w odniesieniu do badań analitycznych i numerycznych pojedynczego elementu konstrukcji. Celem było wykazanie zgodności obranych metod wyznaczania parametrów wytrzymałościowych belki wspornikowej oraz dobranie najlepszego przekroju poprzecznego w optymalizacji konstrukcji. Analitycznie oraz numerycznie wyznaczono strzałkę ugięcia belki oraz wartość maksymalnych naprężeń zredukowanych (wg Hubera von Misesa). Analizę numeryczną, z użyciem metody elementów skończonych, oraz optymalizację przeprowadzono w środowisku ANSYS. Na podstawie analizy statycznej konstrukcji przeprowadzono optymalizację masy belki poprzez zmianę jej wymiarów przekroju poprzecznego, przy uwzględnieniu wskazanych w pracy kryteriów optymalizacyjnych. W wyniku optymalizacji zostały wybrane rozwiązania spełniające wymagane kryteria. Masa konstrukcji została zmniejszona o połowę w porównaniu do wartości początkowych projektowanej konstrukcji. Dopuszczalne naprężenia nie zostały przekroczone.
EN
The problem of analysing complex steel structures in relation to analytical and numerical tests of a single structure element has been presented. The aim was t o demonstrate the compliance of the chosen methods for determining the strength parameters of a cantilever beam and to select the best cross-section for the optimization of the structure. The beam deflection and the value of the maximum reduced stresses (according to Huber von Mises’ hypothesis) have been determined numerically and analytically. Numerical analysis, on the basis of the finite element method, as well as the optimization, have been performed in the ANSYS environment. Based on the static analysis of the structure, optimization of the beam mass has been made by changing its cross-section dimensions, taking into account the specific optimization criteria, pointed in the work. As a result of optimization, solutions satisfying the required criteria have been selected. The weight of the structure has been reduced by half compared to the initial values of the designed structure. The permissible stresses have not been exceeded.
EN
The one of purposes of this paper is to estimation some impact on the service life of the high-pressure cylinder rotor of a typical high-speed turbine K-1000-60/3000. The residual life assessment of power equipment would require determining viability and damage of its base metal. Typical degradation mechanisms of steam turbine equipment include long-term strength reduction and low cycle fatigue accumulation. Intensity of their impact is determined by a numerical examination of equipment thermal (TS) and stress strain states (SSS) for standard operation modes. To perform a numerical examination of the stress strain state would require solving a thermal conductivity boundary problem in quasi-stationary (for nomal operation modes) and nonstationary models (for transients). It is convenient to solve such problems of mathematical physics through discretization of the calculation object using the finite element method (Chernousenko et al. 2018). The service life of steam turbine is determined as an individual one and is assigned based on the results of individual an inspection of a separate element or the largest group of single-type equipment elements of the considered plant. The fleet service life being reached is followed by diagnostics of specific units of power installations and analysis of their operation, measurement of actual dimensions of components, examination of structure, properties and damage accumulation in the metal, non-destructive testing and estimate of stress strain state and residual service life of the component. The results of performed studies are used to determine an individual service life of each element of energy equipment (Nikulenkov et al. 2018).
EN
This paper deals with the investigation of temperature field distribution around the high-current electric contact. The analyses of temperature field were realised in simulation environment ANSYS and provide better understanding why the electrical contact position influences the heat dissipation. Material of electrical contact was copper, aluminium, brass and non-standard material for power devices, silver. Results were compared and the conclusion with the recommendation were stated in the end of this paper.
PL
Artykuł dotyczy badania rozkładu pola temperatury wokół wysokoprądowego styku elektrycznego. Analizy pola temperatury zostały przeprowadzone w środowisku symulacyjnym ANSYS i pozwalają lepiej zrozumieć, dlaczego położenie styku elektrycznego wpływa na rozpraszanie ciepła. Materiałem styku elektrycznego była miedź, aluminium, mosiądz oraz niestandardowy materiał do urządzeń zasilających, srebro.
EN
So far, certain approaches have been developed to extension of service life of equipment in the different stages of metal physical exhaustion. The possibility of defining operating conditions of plant equipment beyond the fleet service life becomes even more relevant with increased operating time. The service life is determined as an individual one and is assigned based on the results of individual an inspection of a separate element or the largest group of single-type equipment elements of the considered plant. The fleet service life being reached is followed by diagnostics of specific units of power installations and analysis of their operation, measurement of actual dimensions of components, examination of structure, properties and damage accumulation in the metal, non-destructive testing and estimate of stress strain state and residual service life of the component. The results of performed studies are used to determine an individual service life of each element of energy equipment.
EN
A single point cutting tool is modeled out of two different materials having desired thermoelectric properties. The tool material used is Boron Carbide (B4C) doped with different compositions of Titanium Carbide (TiC). In the present work, three different compositions of Titanium Carbide doped on both sides of cutting tool made by Boron carbide. The available combinations of Titanium Carbide (TiC) from the work bench in ANSYS was selected with three cases of 0 & 25.4%, 0% &12.5% and 12.5% & 25.4% on first half and second half of the cutting tool respectively. The simulation process is done in ANSYS 2020 R2 software, thermal-electric module (TEM) is used. From these studies it is evident that considerable cooling effect is achieved and found to be the lowest temperature of 10.93°C is observed for the combination of 0% &25.4%, 18.79°C is observed for the combination of 0& 12.5% and 26.73°C for 12.5% and 25.4% combination at the junction of the tool material which is nearer to the cutting tip respectively. Finally it is concluded that one side of cutting tool without any doping and other side with 25.4% TiC doped showed good results which observed by conducting number of simulations at different levels of iterations for Titanium Carbide doped Boron Carbide cutting tool used in turning operation.
EN
The article presents the results of the analyzes on the influence of the optimization self-supporting staircase geometry on its strength and dynamic properties. The primary goal was to achieve a structure with a lower mass. The Topology Optimization tool from the ANSYS package allowed to the elimination of the finite elements carrying the smallest stresses from the structure. The iterative approach resulted in a systematic reduction of the model mass up to decrease by 40 (%). The reduction in the structure led to a decrease in its strength - the safety factor decreased from 5.95 to 4.92. The influence of the optimization of the structure on its dynamic properties was determined as an additional aim of the study.
PL
Artykuł przedstawia wyniki analiz dotyczące wpływu optymalizacji geometrii klatki schodowej o konstrukcji samonośnej na jej właściwości wytrzymałościowe oraz dynamiczne. Podstawowym celem było uzyskanie konstrukcji o mniejszej masie. Wykorzystanie narzędzia Topology Optimization z pakietu ANSYS pozwoliło na wyeliminowanie z konstrukcji elementów skończonych przenoszących najmniejsze naprężenia. Iteracyjne podejście skutkowało systematyczną redukcją masy modelu aż do założonego jej spadku o 40 (%). Redukcja ta doprowadziła do nieznacznego zmniejszenia wytrzymałości konstrukcji - współczynnik bezpieczeństwa zmniejszył się z poziomu 5,95 do 4,92. Jako dodatkowy cel badania założono ustalenie wpływu przeprowadzenia optymalizacji konstrukcji na jej cechy dynamiczne.
EN
Purpose: The operation of engineering structures may cause various type of damages like cracks, alterations. Such kind of defects can lead to change in vibration characteristics of cantilever beam. The superposition of frequency causes resonance leading to amplitude built up and failure of beam. The current research investigates the effect of crack dimensional parameters on vibrational characteristics of cantilever beam. Design/methodology/approach: The CAD design and FE simulation studies are conducted in ANSYS 20 simulation package. The natural frequencies, mode shapes and response surface plots are generated, and comparative studies are performed. The effect of crack dimensional parameters is then investigated using Taguchi Design of Experiments. The statistical method of central composite design (CCD) scheme in Response Surface Optimization is used to generated various design points based on variation of crack width and crack depth. Findings: The research findings have shown that crack depth or crack height have significant effect on magnitude of deformation and natural frequency. The deformation is minimum at 0.009 m crack height and reaches maximum value at 0.011 m crack height. Research limitations/implications: The crack induced in the cantilever beam needs to be repaired properly in order to avoid crack propagation due to resonance. The present study enabled to determine frequencies of external excitation which should be avoided. The limitation of current research is the type of crack studied which is transverse type. The effect of longitudinal cracks on vibration characteristics is not investigated. Practical implications: The study on mass participation factor has shown maximum value for torsional frequency which signifies that any external excitation along this direction should be avoided which could cause resonance and lead to amplitude build up. Originality/value: The beams are used in bridge girders and other civil structures which are continuously exposed to moist climate. The moisture present in the air causes corrosion which initiates crack. This crack propagates and alters the natural frequency of beam.
EN
In this investigation, the effective mechanical, coupling and dielectric properties of Macro-fiber-composites (MFCs) consisting of piezorod-element constituents are determined using representative volume element method combined with finite element analysis. Experiments are conducted on piezo-bar-element MFCs to understand the applicability of the proposed approach which would later be extended to composites with modified geometric pattern. The longitudinal strains with respect to static deflections of beam and forced displacements under varying electrical loads are measured for the MFCs, and compared with the numerical simulations. Based on the good agreement from the result comparisons of piezo-bar-element MFCs, the effective material properties of piezo-rod-element MFCs are numerically determined based on the RVE approach.
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