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EN
The article presents model of the Radio–communications Platform supporting Inland Navigation. The model of integrated satellite, analog and digital radio – communications systems has been presented. Individual blocks included in the module architecture has been developed. A communication model which integrates the Galileo system with Inland-AIS for the purpose of obtaining a reliable position in limited waters has been presented. The functional requirements of the Galileo Satellite System for integration with Inland-AIS in restricted areas was characterized. The integration of satellite systems was analysed in order to improve the compatibility of Communication Systems.
EN
This paper concerns the modeling and analysis of machine elements using the adaptive finite element method. The adaptation used is of hpq type, which means that the finite element dimension h and element transverse q and longitudinal p approximation order may be different in each element. These parameters are determined automatically by the program to obtain modeling and approximation error levels not higher than the assumed admissible level of the errors. The presented paper focuses on the use of transition elements between basic elements corresponding to the three-dimensional theory of elasticity and the first-order shell model. Three applied transition elements differ in their assumptions regarding the continuity of the displacement, strain, and stress fields between the basic models. The effectiveness of the application of transition elements was assessed in terms of the removal of the internal boundary layer at the boundary between the models and the convergence of adaptive solutions taking into account these models.
PL
Druk 3D jest znany jako "produkcja addytywna", tj. technologia polegająca na tworzeniu trójwymiarowych obiektów poprzez nakładanie na siebie warstw materiału. Obecnie znajduje zastosowanie w wielu dziedzinach, w tym: produkcji prototypów, medycynie, lotnictwie i kosmonautyce. W prototypowaniu druk 3D pozwala znacznie przyspieszyć proces projektowania i obniżyć koszty dzięki możliwości wczesnego testowania różnych wersji prototypu. W planowaniu infrastruktury miejskiej druk 3D pozwala na produkcję realistycznych modeli całych miast lub poszczególnych elementów, takich jak mosty, drogi czy osiedla mieszkaniowe. Daje to możliwość późniejszej szybkiej modyfikacji projektów i dostosowania ich do zmieniających się potrzeb miasta. W niniejszej pracy przedstawiono przykłady wykorzystania wybranych technologii druku (FDM i CJP) w prototypowaniu i planowaniu przestrzennym.
EN
3D printing is known as 'additive manufacturing' i.e. a technology that involves creating three-dimensional objects by adding layers of material on top of each other. Currently, it is used in many areas, including: prototype production, medicine, aviation and cosmonautics. In prototyping, 3D printing allows tosignificantly speed up the design process and reduce costs thanks to the possibility of early testing of different versions of the prototype. In planning urban infrastructure, 3D printing allows on production of realistic models of entire cities or individual elements, such as bridges, roads or housing estates. This makes a possibility to quickly modify projects later and adapt them to the changing needs of the city. This work presents examples of the use of selected printing technologies (FDM and CJP) in prototyping and spatial planning.
EN
The ground movements related to the presence of old underground cavities are often damaging to structures and infrastructures. Considering these ground movements in calculations will prevent considerable human loss and material damage. Many areas, both in Algeria and in abroad, are prone to instability caused by ground rupture and the phenomenon of sinkhole progression. The objectives of this work are first to numerically simulate the process of cavity collapse and second to analyze the impact of cavity properties on structure stability. A finite element model was established to analyze the influence of several cavity parameters (dimensions, volume, and spacing). Validation of the model relied on comparing numerical results with experimental data from scientific research, as well as those from analytical approaches. Adequate correlation was achieved. The study allowed deriving mathematical equations relating to several parameters, including cavity dimensions and position in the soil, soil characteristics, and footing width. These results will be considered to reduce the risk of surface structure instability.
EN
By the method of numerical simulation, the heat transfer from the room to the environment through a system of two double-chamber windows, into the gap between which ventilation air from the room supplies, is being researched. Distributions of air velocity and temperature in the chambers of double-chamber windows and in the gap between double-chamber windows are determined. The influence of the flow of ventilation air entering the space between the double-chamber windows on the amount of heat transferred from the room to the space between windows through the inner window and the amount of heat removed from the gap to the environment through the external double-chamber window is investigated. The energy advantages of the method of removing ventilation air through the gap between double-chamber windows over the method of direct removal of ventilation air from the room to the environment are determined.
PL
Wykonano badania reometryczne polimerowego kompozytu drzewnego na osnowie polipropylenu (PP) oraz opracowano jego charakterystyki reologiczne, wyznaczając parametry równania Kleina i równania Ostwalda i de Waele’a. Wykonano badania symulacyjne procesu wytłaczania celem dokonania oceny zastosowanych modeli reologicznych. Stwierdzono, że można uzyskać dobre wyniki modelowania procesu wytłaczania przy zastosowaniu stosunkowo prostego modelu reologicznego Ostwalda i de Waele’a. W przypadku tego modelu dostępne bazy materiałowe dostarczają znacznie więcej danych, niż w przypadku modelu Kleina.
EN
Rheometric studies of a polypropylene-based wood plastic composite were performed and its rheological characteristics were developed by determining the parameters of the Klein and Ostwald-de Waele equations. Simulation studies of the extrusion process were performed to evaluate the applied rheological models. Good results for modeling the extrusion process were obtained by using a relatively simple Ostwald-de Waele rheological model. For this model, the available material databases provide much more data than for the Klein model.
PL
Opracowano metodykę modelowania transportu granulatu w wytłaczarce jednoślimakowej na podstawie mechaniki ośrodków dyskretnych. Przedstawiono koncepcję wykorzystania wyników tego modelowania do opracowania globalnego modelu procesu wytłaczania. Modelowanie przeprowadzono w rzeczywistej, trójwymiarowej przestrzeni przepływu wytłaczarki, przy różnych geometrycznych, technologicznych i materiałowych parametrach procesu.
EN
A method for modeling the granulate transport in a single screw extruder based on discrete media mechanics was developed. A concept for using the results of the modeling to develop a global model of the extrusion process was presented. The modeling was performed in the real, three-dimensional flow domain of the extruder, with various geometric, operating and material process parameters using the Altair EDEM program.
PL
Przedstawiono wyniki badań dotyczących zastosowania mezoporowatej krzemionki SBA-15 jako adsorbentu lidokainy. Przeprowadzono modelowanie procesu adsorpcji z zastosowaniem wielu równań izoterm (Freundlicha, Langmuira, Jovanovicia oraz Dubinina i Raduszkiewicza). Wartości parametrów modeli matematycznych oszacowano metodą dopasowania nieliniowego. Izoterma Jovanovicia najlepiej opisywała adsorpcję lidokainy na krzemionce SBA-15. Wykazano (model Dubinina i Raduszkiewicza) fizyczny charakter odziaływań leku z powierzchnią adsorbentu SBA-15.
EN
Lidocaine was adsorbed from its solns. in MeCN on a SBA-15 mesoporous silica. The modeling of adsorption exptl. data was performed using several adsorption models such as Freundlich, Langmuir, Jovanovich and Dubinin-Radushkevich. The values of the math. model parameters were estimated using the nonlinear fitting method. The adsorption process onto SBA-15 silica was best described using Jovanovich isotherm. The phys. nature of the drug interactions with the SBA-15 adsorbent surface was demonstrated (Dubinin and Raduszkiewicz model).
PL
Przedstawiono wyniki badań symulacyjnych procesu wtryskiwania przy zastosowaniu różnych modeli orientacji krótkich włókien szklanych oraz różnych metod dyskretyzacji modelu wypraski z poliamidu 6 z 50-proc. zawartością włókien (PA6GF50). Wyniki numerycznych prób rozciągania dla symulowanych próbek zestawiano z wynikami doświadczalnych badań wytrzymałości. Stwierdzono wpływ zarówno modelu matematycznego, jak i typu siatki elementów skończonych na dokładność numerycznie wyznaczonych właściwości mechanicznych wtryskiwanego wyrobu. Badania symulacyjne przeprowadzono za pomocą najnowszych wersji zaawansowanych programów symulacji procesu wtryskiwania Moldex3D i Cadmould.
EN
Simulation studies of the injection molding process using various models of short glass fiber orientation and methods of mold model discretization for polyamide 6 with a glass fiber content of 50% were presented. The results of numerical tensile tests for simulated samples were compared with the results of exptl. strength tests. The effect of both the math. model and the type of finite element mesh on the accuracy of numerically detd. mech. properties of the injected product was found. The simulation studies were performed using Moldex3D and Cadmould programs.
PL
W związku z upowszechnieniem się farm wiatrowych pojawia się potrzeba budowy modeli złożonych systemów energetycznych. Modele dające dokładniejsze wyniki wymagają wzięcia pod uwagę większej liczby czynników wejściowych. W modelu systemu energetycznego turbin wiatrowych jako źródeł energii wymagane jest uwzględnienie zmienności wiatru. Zatem aby możliwe było budowanie lepszych modeli systemów energetycznych, konieczne jest opracowanie dyskretnego modelu turbiny wiatrowej. W pracy podjęto się opracowania takiego modelu i zaimplementowania go w języku Modelica w środowisku OpenModelica. Wybór uniwersalnego języka modelowania pozwala na wykorzystanie opracowanego modelu w wielu komercyjnych środowiskach obliczeniowych.
EN
A discrete wind turbine model was developed and implemented in the Modelica language in the OpenModelica environment. The developed model was verified by comparison with profile characteristics generated using Qblade software and verified on the basis of exptl. data for RISØ wind turbines. The choice of a universal modeling language allows the use of the developed model in many com. computing environments.
EN
Computer processing of geological data is widely used to process geological information. Therefore, an assessment of the structures as potential reservoir traps for oil and gas was carried out on the basis of quantitative parameter analysis. This approach made it possible to reasonably confirm certain regularities. To identify these regularities in the relationships between the numerical parameters of complex structures, computer geological and statistical modeling of the studied objects of the Boryslav-Pokuttya zone was carried out using correlation and cluster analysis. In general, correlation analysis allows analyzing the set of determined values and is aimed at identifying and studying the systems that form some values included in this set. Classification of any objects by meaningful groups is carried out by the method of cluster analysis. To model the processes that formed local structures and to determine the patterns of their spread, a large volume of quantitative indicators was processed. On the basis of quantitative indicators, it was possible to evaluate the results of studies of the tectonic stresses and deformations distribution, which will contribute to more reliable determination of reservoir potential for oil and gas. In turn, this will significantly increase the geological effectiveness of oil and gas exploration in the Boryslav-Pokuttya area. The contemporary form of structures and their spatial arrangement result from the long-termimpact of tectonic forces over geological time. Different manifestations of tectonic activity in successive geological epochs leads to specific changes in the structural plan of geological formations, influencing the potential oil and gas content within them (formation, unforming, and reforming of traps and, accordingly, hydrocarbon reservoirs). The structures of the Boryslav-Pokuttya zone have undergone a complex and lengthy formation process: from the formation of flysch folds to very complex structural forms. This complexity is contributed to the influence of the magnitude and nature of the tectonic forces. The morphological diversity of the structures, can be described by numerical parameters, which can be used as a basis for classifying these structures in the Boryslav-Pokuttya zone.
PL
Komputerowe przetwarzanie danych geologicznych jest szeroko stosowane do przetwarzania informacji geologicznej. W związku z tym przeprowadzona została ocena struktur, jako potencjalnych pułapek złożowych dla ropy i gazu, na podstawie analizy parametrów ilościowych. Takie podejście pozwoliło racjonalnie potwierdzić pewne prawidłowości. W celu identyfikacji tych prawidłowości w relacjach pomiędzy parametrami numerycznymi złożonych struktur, przeprowadzono komputerowe modelowanie geologiczne i statystyczne badanych obiektów strefy borysławsko-pokuckiej, z wykorzystaniem analizy korelacji zmiennych oraz analizy skupień. Zasadniczo analiza korelacji zmiennych pozwala analizować zbiór określonych wartości i ma na celu identyfikację i badanie zespołów, które tworzą pewne wartości zawarte w tym zbiorze. Natomiast klasyfikacja dowolnych obiektów za pomocą istotnych grup jest przeprowadzana metodą analizy skupień. Celem modelowania procesów, które utworzyły lokalne struktury i określenia wzorców ich występowania, przetworzono dużą liczbę wskaźników ilościowych. Na podstawie wskaźników ilościowych możliwa jest ocena wyników badań rozkładu naprężeń i deformacji tektonicznych, co przyczyni się do bardziej wiarygodnego określenia potencjału złożowego dla ropy i gazu. To z kolei powinno pozwolić na znaczne zwiększenie efektywności geologicznej poszukiwań ropy i gazu w obszarze jednostki borysławsko-pokuckiej. Współczesna forma struktur i ich układ przestrzenny wynikają z długotrwałego oddziaływania sił tektonicznych w czasie geologicznym. Różnego typu przejawy aktywności tektonicznej w poszczególnych epokach geologicznych prowadzą do określonych zmian w planie strukturalnym formacji geologicznych, a tym samym wpływają na potencjalną zawartość w ich obrębie ropy i gazu (formowanie, deformacja i ponowne formowanie pułapek, a tym samym złóż). Struktury w strefie borysławsko-pokuckiej przeszły złożony i długotrwały proces formowania: od formowania fałdów fliszowych do bardzo złożonych form strukturalnych, co jest wynikiem oddziaływania sił tektonicznych o zróżnicowanym charakterze i wielkości. Odmiany morfologiczne struktur można opisać za pomocą parametrów liczbowych, które mogą posłużyć jako podstawa do klasyfikacji tych struktur w strefie borysławsko-pokuckiej.
EN
Few high magnitude earthquakes were generated worldwide in the last three and a half years, some of which triggered tsunami waves. We took into account all the events during the interval January 2020 - June 2023. There was a total of 15 earthquakes (5 in 2020, 5 in 2021, 2 in 2022, 2 in 2023) which lead to moderate and/or small tsunami waves (above 0.1 m), having magnitudes higher than 7, but also one earthquake with magnitude below 7 (6.8) which lead to very small tsunami waves generation. Not all the high magnitude earthquakes resulted in tsunami waves, depending on the depth, focal mechanism and / or other parameters (distance to shore, local conditions, etc.). From tsunami measurements point of view, we considered the most relevant ones and studied only the events that lead to measured waves higher than 0.5 m. The most significant ones are 5 events: 23rd of June 2020 (15:29 UTC), Near Coast of Oaxaca Mexico, M7.4 (maximum waves 0.68 m); 19th of October 2020 (20:55 UTC) South of Alaska M7.4 (maximum waves 0.76 m); 10th of February 2021 (13:20 UTC) Southeast of Loyalty Island, M7.7 (maximum waves 0.78 m); 4th of March 2021 (19:28 UTC) Kermadec Island region, M8.1 (maximum waves 0.56 m) and 19th of September 2022 (18:05 UTC), Coast of Michoacan Mexico M7.6 (maximum waves 0.79 m). We compared, in this paper, the values of sea level measurements with the results of the tsunami simulations, using the parameters of each earthquake (latitude, longitude, magnitude, depth, focal mechanism). The modeling simulations were accomplished using TRIDEC Cloud software, provided by the German Research Centre for Geosciences (GFZ), Potsdam, Germany. When comparing the values between the two types of data (measured vs. computed), the results show that some simulations overestimate the measured values, others underestimate it. More studies are necessary for a better numerical assessment of sea level, in order to be more precise and closer to the real measurements. Future work might include using two or three different modeling software, for the same earthquake parameters, and comparing the results.
EN
A critical parameter of IoT nodes and WSN nodes is runtime. In most cases, nodes are battery-powered. The use of Energy Harvesting based power systems in the nodes allows to extend the operating time. Modeling and simulation of circuits using Energy Harvesting makes it possible to achieve optimal circuit design before physical implementation. This article presents the design and simulation process of a power system using a micro photovoltaic panel for energy support.
PL
Krytycznym parametrem węzłów IoT oraz węzłów sieci WSN jest czas pracy. W większości przypadków węzły zasilane są w sposób bateryjny. Wykorzystanie w węzłach układów zasilania bazujących na układach Energy Harvesting pozwala wydłużyć czas pracy. Modelowanie i symulacja układów wykorzystujących Energy Harvesting pozwala na osiągniecie optymalnej konstrukcji układu przed przystąpieniem od fizycznej realizacji. W niniejszym artykule przedstawiony jest proces projektowania i symulacji układu zasilania wykorzystujący do wspomagania energetycznego mikro panel fotowoltaiczny.
EN
The increasing use of drone technology to produce high-resolution digital imagery and elevation models has been associated with a growing interest in developing quantitative morphometric analysis (QMA). QMA analysis is an invaluable part of creating detailed topographic models in landslide scars that are still highly unstable and prone to erosion. This paper presents the results of a research that aims to create a topographic model in a landslide scarred area where the slope configuration is still varied. The study area was located in the landscape of the Cretaceous-Tertiary volcanic transition where many landslides have occurred. Three landslides were selected on the basis of different soil material characteristics that affect the topographic condition of the landslide scar. Aerial photography was recorded using a UAV with a flying height of 80 m, with an orthomosaic resolution of 1 cm. In detail, three morphometric variables (slope, plan curvature, topographic position index) were selected and calculated with the output evaluated based on visual-spatial interpretation. The results showed that morphometric variables performed well in modeling land surface topography. Steep slopes and surfaces with convex curvature are abundant at the ledges and landslide heads that allow water runoff to disperse as the initiation of gully erosion. The multidimensional gully erosion network is concentrated at relatively low elevations and surfaces with concave curvature. The undulating micro-relief of the land surface as a result of the process of material disposition builds up on each other to a gentle slope. Finally, the topographic model of the landslide surface can be used as a base material in implementation of both physical and vegetative land conservation strategies.
EN
The significant production of sewage sludge by wastewater treatment plants on a global scale and the lack of correspondence between housing development and the expansion of sanitation infrastructure indicate a genuine concern regarding environmental preservation. This study addresses the crucial issue of effective sewage sludge management and its environmental impact. In the context of searching for new drying methods that optimize energy use and effectively stabilize sewage sludge, this work investigated the drying behavior of sewage sludge from treatment plants in two northern Moroccan cities using a prototype of an indirect forced convection solar dryer. The drying experiments enabled the determination of drying kinetics as well as highlighted the influence of temperature and humidity on the drying rate. The characteristic drying curve (CDC) and its mathematical expression were determined using Van Meel’s formalism. Thermal diffusivity of wastewater sludge during drying was also investigated. Using Fick’s diffusion model, diffusion coefficients ranged between 0.59 × 10-9 m2/s and 1.43 × 10-9 m2/s, demonstrating an increase in effective diffusivity with rising temperature. The Arrhenius equation provided activation energy values of 16.80 kJ/mol for Oujda samples and 19.72 kJ/mol for Nador samples, indicating the effect of temperature on effective diffusivity. A new equation based on the Midilli-Kucuk model was proposed to predict the drying behavior under untested aerothermal conditions, considering drying temperature and the initial dryness. This study offers a comprehensive analysis of the drying kinetics and effective diffusivity of sewage sludge, providing valuable insights for designing large dryers for sludge management in WWTPs. This approach presents an optimal solution for drying and stabilizing sludge, contributing to environmental preservation efforts.
EN
This study aims to optimize chitin extraction conditions by reducing water and chemical consumption using a twolevel factorial design approach. Two variables were studied for the demineralization process: the volume of hydrochloric acid (400 to 500 mL) and the demineralization time (1 to 1.5 hours) at room temperature. For deproteinization, the variables examined were NaOH concentration (0.6 to 1 mol/L) and deproteinization time (1 to 1.5 hours) at 70–80 °C. The ash and protein contents were measured to evaluate the efficiency of the demineralization and deproteinization processes, respectively. Minitab 18 software was used for the experimental design. The results showed that the best conditions for extracting high-quality chitin are a demineralization time of 1 hour, an HCl volume of 500 mL, a NaOH concentration of 1 M, and a deproteinization time of 1 hour. These optimal conditions reduce the amount of water, time, and chemicals required for chitin extraction. Compared to previous studies, we significantly reduced the amount of water and chemicals as well as the extraction duration. These results are innovative as they offer a more efficient and sustainable solution for chitin extraction, thus filling a gap in current research by proposing an optimized method. By providing these new data and demonstrating their effectiveness, our research makes a significant contribution to improving chitin extraction techniques, addressing an unmet need in the industrial field.
EN
The hydrological regimes of all Moroccan basins are characterized by significant inter-annual variability, with alternating wet and dry years, interspersed with periods of intense hydrology or severe drought. Most watersheds are short of water. Climate change and the increasing frequency of severe events, particularly sudden drops in precipitation and widespread drought, are likely to exacerbate this situation. Like the severe drought years that hit Morocco from 1980 to 1985, 1990 to 1995, 1998 to 2002, 2011 and 2015 to 2020, the threat of drought still hangs over the country. During these years, almost all watersheds experienced water shortages, leading to overexploitation of groundwater. The aim of this research is to explain the climate of the Bouregreg watershed and the effects of climate change on its water resources. In order to preserve a more sustainable environment for future generations, it is crucial to assess the vulnerability of this area and the possible effects of climate change on hydrology. The results find after treatment of data confirmed previous research concerning the increase in temperatures and the decrease in precipitation which has been carried out in northern Morocco. RCPS scenarios (2.6; 4.5 and 8.5) shows that the research region will become dry. Getting from 0.8 to 1.3°C on an annual basis is planned for the 1920s and 2030s, as well as a modest increase in the frequency of days with summer waves.
EN
This research aims to provide a fault diagnosis approach for Hybrid Dynamic (SDHs), Systems and FaultTolerant Control synthesis, while also ensuring the smooth operation of industrial settings. This study is a part of the larger topic of Hybrid Dynamic System control and fault diagnosis. The primary focus is on modelling strategies designed expressly for Hybrid Dynamic Systems, with a concentration on combining continuous and event-driven components. Much work is devoted to developing a model that can incorporate both kinds of elements. A system model that can track several modes without explicit identification can be created by utilizing Neuro-Fuzzy Networks, providing a thorough overview. On the basis of this synthesized model, an AI-based fault diagnosis method is subsequently developed.
EN
Fluid-flow approximation is an approach to modelling and evaluating the performance of vast computer networks. Due to varying traffic and performance of transmission protocols reacting to traffic overloads, computer networks are in a permanent transient state. The fluid-flow method main advantage is its ability to analyse these transient states. The article reviews and organises several versions of this approach, indicating a few errors. The main reason for these errors is confusion or lack of distinction between the two versions of the Internet Protocol – when the queue of packets at a node is too long, they may be destroyed or only marked as redundant. The paper compares and evaluates these fluid-flow approximation models with mild and aggressive settings of RED parameters. The authors build a software system with hitherto unprecedented capabilities regarding the size of the networks to be analysed and with innovative way of organising the calculations. The paper shows how large differences imprecise assumptions can introduce in quantitative results.
EN
Modeling the behavior and shape of space objects is widely used in modern astrophysical research methods. Such studies are often used to determine the shape and modeling of physical parameters of variable stars and asteroids. Therefore, based on the database of photometric observations of resident space objects (RSO) available in the Laboratory of Space Research of Uzhhorod National University, it was decided to find a means for modeling light curves to confirm the shape of objects and determine the parameters of their rotation by analogy with objects in deep space. We attempted to use Blender software to model the RSO synthetic light curves (LCs). While Blender has been a popular open-source software among animators and visual effects artists, in recent years, it has also become a tool for researchers: for example, it is used for visualizing astrophysical datasets and generating asteroid light curves. In the process of modeling, we used all the advantages of Blender software such as Python scripting and used GPU. We made synthetic LCs for two objects – TOPEX/Poseidon and COSMOS-2502. A 3D model for Topex/Poseidon was available on the NASA website, but after research of official datasheets, we figured out that the available 3D model requires corrections in the dimensions of the RSO body and solar panel. A 3D model of COSMOS-2502 was made according to available information from the internet. A manual modeling process was performed according to well-known RSO’s self-rotation parameters. For example, we also show the results of LC modeling using the Markov chain Monte Carlo (MCMC) method. All synthetic LCs obtained in the research process are well correlated with real observed LCs.
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