Wyniki wyszukiwania - BazTech

1

Modeling of a power unit using a photovoltaic energy harvester

Dziadak Bogdan, Sabry Ahmad H., Almamoori Nawres Ali, Kucharek Mariusz

Elektronika : konstrukcje, technologie, zastosowania

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2024

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Vol. 65, Nr 1

14--18

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. Mo delowanie i symulacja układów wykorzystujących Energy Harve sting pozwala na osiągniecie optymalnej konstrukcji układu przed przystąpieniem od fizycznej realizacji. W niniejszym artykule przed stawiony jest proces projektowania i symulacji układu zasilania wykorzystujący do wspomagania energetycznego mikro panel fotowoltaiczny.

2

Modelling of proffesional competences in health care units – preliminary assumptions

Krawczyk-Sołtys Agnieszka, Płatkowska-Prokopczyk Laura

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2023

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z. 169

439--450

EN

Purpose: The aim of the article is to present the theoretical assumptions of the model of professional competencies in health care units. It was assumed that competences are a multidimensional concept and require an integrated approach that allows for the construction of a competency model that reflects their real complexity. A list of professional competencies will be presented, which will be subject to empirical verification in the course of future research by the authors in order to identify key competencies. Design/methodology/approach: The proposed lists of professional competencies (six domains) was created and are based on the analysis of healthcare competencies models the study of the literature - and the Authors’ observations of the analyzed entities. Findings: Presented model of professional competencies in health care units contains six domains with sub-competencies. The importance of assessing competences is undeniable. Competence recognition offers a way to develop workforce planning and career opportunities of practicing medical staff. Having an instrument that identifies existing competences and those that need to be acquired becomes significant for distinguishing the singularity of actions for a professional practice which is safe, humane and with no risk to the client, the medical staff or the health care organization. Originality/value: An identification the professional competencies of health care units managers significantly shaping competences of such organizations especially relevant in pandemic time.

3

Multigraph is: Part 1. A formal description of railway infrastructure for the digital twin of the ETCS application

Kochan Andrzej, Folęga Piotr, Skirkus Remigijus, Bureika Gintautas

Transport Problems

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2023

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T. 18, z. 2

43--52

EN

The European Railway Agency has formulated assumptions for a target model of rail transport. Its important premise is digitalization to support the communication and transport services that the railways will make available to the public in the future. Part of the digitalization process is the digital description of the railway infrastructure in a formalized form to allow algorithmic processing. The formal description of infrastructure is not a new issue. However, attempts made so far have not resulted in a permanent definition of a generally accessible formalism allowing for a coherent representation of the physical railway infrastructure in a digital form. This paper presents the results of work carried out within the research project Digital Railway-The Digital Twin of the ETCS Application-Virtual Prototyping and Simulation of Operational Scenarios.

4

Modeling and simulation of the furniture manufacturing and assembly process in the Arena simulation software

Kolny Damian, Kaczmar-Kolny Ewa, Dulina Ľuboslav

Technologia i Automatyzacja Montażu

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2023

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nr 1

13--22

EN

The article describes issues related to creating discrete simulation models for the implementation of the furniture manufacturing and assembly process in a furniture company. The methodology of the manufacturing system analysis was presented, which is aimed to support the appropriate approach to the construction of simulation models. The scope of the work includes the technological identification of the furniture manufacturing and assembly process in real production conditions, on the basis of which the appropriate simulation model was built. The course of the process was analyzed in the Arena software on the basis of a computer simulation based on reports. As a result of the simulation of the manufacturing process with the use of information from report of usage, an area for improvement was located. The re-analysis of the material flow made it possible to propose a change in the input parameters for the simulation model in the indicated area. The results of the second simulation show significant changes in the effective use of workstations and increase in the efficiency of the production line. In practice, it can be the basis for introducing simulated changes in the production system.

PL

W artykule opisano zagadnienia związane z tworzeniem dyskretnych modeli symulacyjnych dla realizacji procesu wytwarzania i montażu mebli w przedsiębiorstwie branży meblarskiej. Przedstawiono metodykę analizy systemu wytwarzania, która ma za zadanie wspierać właściwe podejście dla budowy modeli symulacyjnych. Zakresem praca obejmuje identyfikację technologiczną procesu wytwarzania i montażu mebli w rzeczywistych warunkach produkcyjnych, w oparciu o którą zbudowano właściwy model symulacyjny na przykładzie procesu wytwarzania w rzeczywistych warunkach produkcyjnych. Analizę przebiegu procesu na podstawie symulacji komputerowej w oparciu o raporty przeprowadzono w oprogramowaniu Arena. W wyniku przeprowadzonej symulacji procesu wytwarzania z wykorzystaniem informacji z raportu obciążeń stanowiskowych zlokalizowano obszar do doskonalenia. Powtórna analiza przepływu materiałowego pozwoliła zaproponować zmianę parametrów wejściowych dla modelu symulacyjnego we wskazanym obszarze. Wyniki drugiej symulacji wskazują istotne zmiany w zakresie efektywnego wykorzystania stanowisk pracy oraz zwiększenia wydajności linii produkcyjnej. W praktyce może to stanowić podstawę do wprowadzenia symulowanych zmian w omawianym systemie produkcyjnym.

5

Analysis of a web application supporting gym management in terms of control and systems theory

Tchórzewski Jerzy, Nabiałek Wojciech, Księżopolski Artur

Studia Informatica : systems and information technology

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2023

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Vol. 1(28)

47--68

EN

An analysis of the web application supporting the management of the gym was carried out, which was designed in terms of the theory of control and systems. The obtained results of measurements of input and output quantities of selected subsystems were used to carry out the identification, as a result of which models of web application subsystems were obtained. On the basis of the obtained subsystem models, appropriate models were then designed in Simulink for the purposes of simulation and comparative studies of the behavior of subsystem models in relation to real systems that are web applications, including an appropriate analysis of the web application system model was carried out under the name of the gym on its selected subsystems, including in particular the subsystem called Generating a diet. In addition, testing and simulation studies were carried out to check the correct functioning of the web application management system model and the introduction of appropriate changes to the model was proposed, and the obtained research results were discussed, indicating the high accuracy of the obtained web application models.

6

Badania pracy urządzenia regulacyjnego węzłów cieplnych bezpośrednich wykorzystywanego do zarządzania parametrami wody

Wołoszyn Jerzy, Zięba Paweł, Różycki Sławomir

Przemysł Chemiczny

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2023

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T. 102, nr 7

726--730

PL

Przedstawiono wyniki badań symulacyjnych pracy urządzenia regulacyjnego węzłów cieplnych bezpośrednich wykorzystywanych przez obiekty technologiczne i budynki posiadające przyłącza ciepłownicze bezpośrednie. Stwierdzono, że urządzenie może zapewnić wymagane temperatury w szerokim zakresie nastaw i przedstawiono wyniki dla wybranego przypadku.

EN

The operation of the control device of direct heating substations used by technol. facilities and buildings with direct heating connections was simulated using the OpenModelica program. It was found that the device can provide the required temp. in a wide range of settings. The results for a selected case were presented.

7

Precyzyjne wyznaczanie rozkładu kątowego indukcyjności uzwojenia silnika reluktancyjnego przełączalnego z wykorzystaniem dedykowanego, zautomatyzowanego stanowiska laboratoryjnego

Fabiański Bogdan, Zawirski Krzysztof, Pajchrowski Tomasz

Przegląd Elektrotechniczny

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2023

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R. 99, nr 5

177--183

PL

Artykuł opisuje przyjętą metodę uzyskiwania kątowego profilu indukcyjności uzwojenia silnika, w której podstawa jest charakterystyczne przetwarzanie danych pomiarowych uzyskiwanych z dedykowanego stanowiska laboratoryjnego. Podstawą przedstawionej analizy jest badanie przebiegu prądu w towarzystwie wymuszającego go napięcia ujawniając tym samym skończoną dynamikę obwodu RL. Uzasadnieniem użytego określenia precyzyjne jest uwzględnienie nieliniowej funkcji aproksymacji modelującej przebieg prądu w zestawieniu do innych, uproszczonych metod w połączeniu z relatywnie złożonym procesem filtrowania i ekstrakcji wektorów danych. Wybrane parametry procesu poddano analizie statystycznej celem określenia optymalnych nastaw procesu. Uzyskane rezultaty wstępnie sprawdzono pod kątem powtarzalności oraz opisano dalsze kierunki badań.

EN

The article describes the adopted method of obtaining the angular inductance profile of the motor winding. The method basis on the characteristic processing of measurement data obtained from a dedicated laboratory stand. The basis of the presented analysis is the study of the current waveform in the presence of the voltage forcing it, thus revealing the finite dynamics of the RL circuit. The rationale for the precise term used is to take into account the nonlinear approximation function modeling the current waveform in comparison to other, simplified methods. What is equally important, certain parameters of the acquisition process were adopted as a consequence of the performed statistical analysis. Parameterization of the process is possible thanks to the proprietary design of the test stand, which additionally allows for high angular resolution of measurements. The obtained results were initially checked for repeatability and further research directions were described.

8

Modeling the performance of an Electrodynamic screen (EDS) with artificial intelligence techniques

Houari Toufik Ahmed, Dahou Omar, Djilani Kobibi Youcef Islam, Bouchekara Hocine

Przegląd Elektrotechniczny

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2023

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R. 99, nr 4

128--132

EN

Artificial neural networks by their learning, classification, and decision capabilities, have contributed in the development of several fields. In electrostatics and its applications, neural networks are used to solve the problems of modeling, diagnosis and control of different modes of operation of machines. This work focuses on the application of artificial neural networks for modeling the operation of a three-phase electric field electrodynamic screen for moving micronized polyvinyl chloride (PVC) particles, with an average particle size of 250 μm. The neural network used is a multilayer perceptron type network, trained by the gradient back propagation algorithm. The input vector contains parameters taken from the studied experimental device: applied voltage U [kV], frequency [Hz] and diameter d [mm]. The output vector contains the mass of the product collected at the output of the electrodynamic screen.

PL

Sztuczne sieci neuronowe dzięki swoim zdolnościom uczenia się, klasyfikacji i podejmowania decyzji przyczyniły się do rozwoju kilku dziedzin. W elektrostatyce i jej zastosowaniach sieci neuronowe są wykorzystywane do rozwiązywania problemów modelowania, diagnozowania i sterowania różnymi trybami pracy maszyn. W pracy skupiono się na zastosowaniu sztucznych sieci neuronowych do modelowania działania ekranu elektrodynamicznego trójfazowego pola elektrycznego dla poruszających się cząstek mikronizowanego polichlorku winylu (PVC) o średniej wielkości cząstek 250 μm. Wykorzystywana sieć neuronowa jest wielowarstwową siecią typu perceptron, wytrenowaną przez algorytm wstecznej propagacji gradientu. Wektor wejściowy zawiera parametry zaczerpnięte z badanego urządzenia doświadczalnego: przyłożone napięcie U [kV], częstotliwość [Hz] i średnicę d [mm]. Wektor wyjściowy zawiera masę produktu zebraną na wyjściu ekranu elektrodynamicznego.

9

Modeling and simulation of a gold concentrator plant implementing a dissolution loop method

Özdemir Erdem, Dixon Richard, Saari Juha, Kasymova Diana, Tunc Berivan, Bilal Danish, Bayarmagnai Enkhzul, Lang Aleksandra, Koskenkorva Kaija, Larkomaa Jaakko

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 166377

EN

Mineral processing applications increasingly use recycled water to preserve freshwater natural resources and comply with environmental regulations. However, accumulating anions, cations, and reagents in the process water may affect plant flotation performance and production continuity. Therefore, many cost actions may be needed to mitigate the recycled water effects. Typically, the process water properties and their effects on flotation performance are unknown for a greenfield project. Often, the result is an over-scaling up of the process plant with an additional financial cost. The experimental methodology in the paper focuses on creating water for testing that is closer to the actual process water during the comminution and flotation process for any greenfield project. The scope of the study consists of creating possible process water, conducting flotation experiments, and simulation. In order to validate the dissolution loop method, refractory gold flotation plant conditions were selected in our Finland laboratory. The simulation results of dissolution loop flotation kinetics were compared with the actual plant mass balance. According to the comparative results, the process water created by the dissolution loop method has the same physical and chemical properties as the actual process water at the site except for SO4 -concentration. Moreover, comparing the simulation results of the experimental data and plant mass balance studies shows that the gold grade and recovery results in the simulation were lower than the actual plant mass balance.

10

Model estimates of microplastic potential contamination pattern of the eastern Gulf of Finland in 2018

Martyanov Stanislav D., Isaev Alexey, Ryabchenko Vladimir A.

Oceanologia

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2023

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Vol. 65 (1)

86--99

EN

The work is focused on the assessment of microplastics transport and distribution in the eastern part of the Gulf of Finland by means of numerical modeling. In the present study only the riverine sources of microplastics are taken into account. The presented model also accounts for possible sink of suspended microplastic particles into sediments due to simple parameterization of biogeochemical processes such as biofouling and ingestion by zooplankton. Two basic scenarios with different initial fall velocities of suspended microplastic particles, 0.2 m/day and 1.2 m/day, are discussed. The distribution of microplastics coming with the riverine waters of the Neva, Luga, and Narva rivers has been investigated, based on a numerical hydrodynamical hindcast of the year 2018. Model simulations show that the transport of suspended microplastics occurs along the northern coast of the considered area more intensively compared to the southern coast, especially in the easternmost shallow part of the gulf. The results are in a good agreement with other studies focused on the microplastic pollution of the Neva Bay, and with available observational data. The presented results and developed model can be useful tools aimed to assess the intensity and mechanisms of microplastic pollution of the eastern Gulf of Finland. The results can be used in the selection of areas for future environmental monitoring of microplastics pollution of the eastern part of the Gulf of Finland.

11

Modeling of spiral sheet metal elements using Inventor software

Gwizdal Paweł

Mechanik

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2023

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R. 96, nr 11

39--43

EN

This article describes the process of modeling a spiral sheet metal element dedicated to a drum washer for vegetables. The purpose of this element is to transport vegetables through the washer area during the washing process. Modeling performed using the presented method allows to unfold the sheet metal and thus define the dimensions of the input sheet that should be cut from a flat sheet in order to produce a spiral with the desired parameters. This modeling approach can be successfully used to model spirals dedicated to many other applications.

PL

Artykuł zawiera opis procesu modelowania spiralnego elementu blaszanego przeznaczonego dla płuczki bębnowej do warzyw. Zadaniem tego elementu jest transport warzyw przez obszar płuczki w trakcie procesu mycia. Modelowanie przeprowadzone zaprezentowaną metodą pozwala wykonać rozwinięcie blachy, a tym samym zdefiniować wymiary blachy wejściowej, jaką należy wyciąć z płaskiego arkusza, aby możliwe było wykonanie spirali o żądanych parametrach. Takie podejście do modelowania może być z powodzeniem wykorzystane do modelowania spirali przeznaczonych do wielu innych zastosowań.

12

Comparative Simulation of the Production Flow with the Implementation of Kanban and DBR

Tomaszewska Klaudia

Management and Production Engineering Review

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2023

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Vol. 14, No. 2

79--87

EN

Currently, we live in a culture of being overly busy, but this does not translate into efficiency, speed of implementation of the actions taken. Enterprises are constantly looking for methods and tools to make them more efficient. The most popular method of production management is Lean Manufacturing, less known is Theory of Constraints. This work is a continuation of the research on the comparison of these methods with apply a computer simulation, which the analyzed production process in the selected enterprise, after 24 hours and week. An attempt was made to simplify the comparison of the methods based on the obtained simulation in terms of costs. In analyzed case, more advantageous solution is to use the DBR method. To produce various orders that do not require 100% production on the bottleneck position, the use of Kanban is a frequent practice as it provides greater flexibility in order execution.

13

Features of the heat and mass transfer of the underground structures of the Kiev metro with the ground mass and air environment

Deineko Andrii, Krukovskyi Pavlo, Frolov Gennadii

Journal of New Technologies in Environmental Science

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2023

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Vol. 7, nr 1

11--15

EN

On the basis of the experimental values of temperature and absolute humidity of the tunnel air and the temperature of the walls of the rim of the deep tunnels of the Kyiv metro, the features and mutual influence of the earthen massif, the supply air environment and the operating modes of the mechanical system of reversible tunnel ventilation during the year are considered. On the basis of the CFD model, which takes into account the above processes of heat and mass transfer, ventilation modes have been determined that have made it possible to reduce the humidity of a group of tunnels of the Kyiv metro as much as possible.

14

A new idea to increase the convective efficiency of a solar tower air receiver by creating a controlled vortex

Cheilytko Andrii

Journal of New Technologies in Environmental Science

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2023

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Vol. 7, nr 2

46--55

EN

Concentrated solar energy as a source of renewable energy has a high potential for solving the current energy crisis. The solar tower receiver is a crucial element of solar energy conversion efficiency. To increase the convective efficiency of the solar tower receiver, the idea of creating a vortex is proposed. The vortex is created either in the plane in front of the receiver, for flat receivers, or in the internal volume of the receiver, for cavity-type receivers. The calculation formulas for calculating the parameters of the controlled vortex are proposed and computer modeling is performed to determine the effectiveness of the proposed idea. The results of computer modeling confirmed the physical possibility of the controlled vortex formation in the receiver space and visually show the flow structure. Also, the general dependence of the air return coefficient in the VoCoRec receiver on the flow twist was found. Conclusions are drawn on the satisfactory results obtained and on the improvement of the existing model of the controlled vortex.

15

Verification of Dead Zones Generated in Bioreactors as a Proactive Stage in Bioreactor Design

Al-Mashhadani Mahmood K. H.

Journal of Ecological Engineering

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2023

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Vol. 24, nr 6

65--74

EN

The activity and growth of microorganisms for renewable energy production are still influenced by the dead zones created in bioreactors. These areas form a nutrient and thermal gradient, causing an abundance of food in certain areas compared to famines in other areas of same bioreactor. The current study is a step in identifying those dead zones, followed by another step in improving the flow of media inside the reactor. The results indicated that the inner parts of the bioreactor may be a crucial factor in the creation and spread of such dead zones. For example, the position of the disc-type diffuser contributes to the generation of those areas at the bottom of the reactor. It was inferred from the fluid movement in reactors using the annular-type diffuser proposed in the current study. The bubble size, gas mass flux, and radiuses of fillet, as the most important factors, were examined in both bioreactors. The results revealed a noticeable improvement in these parameters in this area of the reactor when the disc diffuser was replaced by the annular diffuser. For example, the average liquid velocity was recorded in the lower part of the modernized reactor at 0.0198 m/s, while the velocity was recorded in the conventional reactor at 0.00077 m/s under same bubbles diameter used in both reactors (0.125 mm). The inclusion of the effect of the presence of microorganisms in mathematical models was also addressed in the current study. The results showed that the amount of oxygen remaining at the bottom of the reactor after bio-consumption in the presence of the annular diffuser was higher than that in the conventional reactor. This clearly emphasizes the importance of the design of the internal parts of the bioreactor.

16

Modeling Radiocesium Contamination of Sunflower Products in the Zaporizhzhia Region

Polevoy Anatolii, Lyashenko Galyna, Zhygailo Olena, Volvach Oksana, Zhygailo Taras, Popovych Iryna, Tolmachova Alla, Kolosovska Valeriya, Kostyukevych Tetyana, Barsukova Olena

Journal of Ecological Engineering

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2023

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Vol. 24, nr 4

279--287

EN

The accident at the Chornobyl nuclear power plant was one of the most serious nuclear incidents in human history. A radioactive plume covered a whole strip of northeastern Europe. The consequences of this catastrophe are still being felt, both in Ukraine and around the world. The article is devoted to the assessment of the consequences of radiocesium contamination of agricultural lands and irrigated waters during a possible accident at the Zaporizhzhia NPP and the associated Cs137 contamination of sunflower products in the Zaporizhzhia region. The studies were carried out using a dynamic mathematical model for the formation of radionuclide activity in the "water-soil-plant-product" system, ECOSIS-87 (Ecoplant). The article presents the results of studies of possible contamination of the environment by radiocesium according the Chornobyl NPP-86 scenario and sunflower production by the method of mathematical dynamic modeling. The calculations were carried out on the basis of the results of an agrochemical and agroecological survey of the state of soils in Ukraine and the Dnipro cascade of reservoirs. If an explosion occurs at the Zaporizhzhia NPP, the power of which will be equal to the Chornobyl NPP, then 100,000 hectares of agricultural land in the region will be taken out of the agricultural production of the Zaporizhzhia region. On agricultural lands where soil contamination with radiocaesium will be more than 5 Ci/km2, and the concentration in irrigated waters will reach 2 Bq/dm3, sunflower, which was grown for seeds to produce oil will need to be replaced with an industrial crop, which will also lead to loss of seed yield sunflower. Crop losses will lead to a decrease in the volume of sunflower oil. It should also be taken into account that the purification of soil and water does not occur in one year. At least in 5 years the situation will begin to improve.

17

A Study on Modeling and Experiment of a Wave Energy Converter Using Mechanical Coupled with Hydraulic Power Take-Off

Cong Binh Phan, Quang Tri Truong, Le Dang Hai Nguyen, Nguyen Long Nhut-Phi

Journal of Ecological Engineering

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2023

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Vol. 24, nr 8

12--24

EN

The article’s proposal refers to a new concept of wave energy converter (WEC), in which the power take-off (PTO) is combined with the mechanical and hydrostatic transmission. Here, the wave energy is absorbed by turning the two-way movement of an incident wave into the one-way rotation of a hydraulic pump which drives a high-pressure (HP) hydraulic circuit. Electricity is generated using a rotating generator which is driven by an HP hydraulic circuit. First, the coupled PTO mechanism is presented to describe the working principle of the proposed WEC. Next, a mathematical model of the buoy connects generator system is shown to analyze the equipment’s performance subjected regular waves. And then, by using the theory of linear potential wave, the hydrodynamic forces acting on the semi-submerged floating buoy and an analytical model of the mechanical transmission coupled with the hydraulic transmission are modeled to investigate the motion of the rotary generator. An experimental Setup is performed to verify the analytical model. Based on the validated model, a structural optimization is calculated to bring the system to resonance condition. Then, a dry test is implemented to analyze the system’s performance. Some optimum parameters are determined and applied to the analytical model, which sends the signal to drive the actuator. As a result, the absorbed efficiency is increased significantly.

18

Development and modeling of the antenna system the direction finder unmanned aerial vehicle

Boiko Juliy, Polikarovskykh Oleksiy, Tkachuk Vitalii

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2023

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T. 13, nr 1

26--32

EN

The article is devoted to the design the proposed construction of the antenna system for the direction-finding complex of the unmanned aerial vehicle (UAV). The experimental part is represented by the results of mathematical modeling the behavior of the antenna in different parts the operating frequency range. The effectiveness of the adopted design solutions was evaluated in comparison with analogues of leading companies in the world. Based on the results of the research, the areas of application the antenna as part of the built-in functional mobile UAV direction finding systems were determined.

PL

Artykuł poświęcony jest zaprojektowaniu proponowanej konstrukcji systemu antenowego dla zespołu radionawigacyjnego bezzałogowego statku powietrznego (BSP). Część eksperymentalna jest reprezentowana przez wyniki matematycznego modelowania zachowania anteny w różnych częściach zakresu częstotliwości pracy. Skuteczność przyjętych rozwiązań konstrukcyjnych została oceniona w porównaniu z odpowiednikami wiodących firm na świecie. Na podstawie wyników przeprowadzonych badań określono obszary zastosowania anteny w ramach wbudowanych funkcjonalnych mobilnych systemów radionamierzania bezzałogowych statków powietrznych.

19

Comparison of the effectiveness of time series analysis methods: SMA, WMA, EMA, EWMA, and Kalman filter for data analysis

Lotysh Volodymyr, Gumeniuk Larysa, Humeniuk Pavlo

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2023

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T. 13, nr 3

71--74

EN

In time series analysis, signal processing, and financial analysis, simple moving average (SMA), weighted moving average (WMA), exponential moving average (EMA), exponential weighted moving average (EWMA), and Kalman filter are widely used methods. Each method has its own strengths and weaknesses, and the choice of method depends on the specific application and data characteristics. It is important for researchers and practitionersto understand the properties and limitations of these methods in order to make informed decisions when analyzing time seriesdata. This study investigates the effectiveness of time series analysis methods using data modeled with a known exponential function with overlaid random noise. This approach allows for control of the underlying trend in the data while introducing the variability characteristic of real-world data. The relationships were written using scripts for the construction of dependencies, and graphical interpretation of the results is provided.

PL

W analizie szeregów czasowych, przetwarzaniu sygnałów i analizie finansowej szeroko stosowane są: prosta średnia ruchoma (SMA), ważona średnia ruchoma (WMA), wykładnicza średniaruchoma (EMA), wykładniczo-ważona średnia ruchoma (EWMA) i filtr Kalmana. Każda z metod ma swoje mocne i słabe strony, a wybór metody zależy od konkretnego zastosowania i charakterystyki danych. Dla badaczyi praktyków ważne jest zrozumienie właściwości i ograniczeń tych metod w celu podejmowania świadomych decyzji podczas analizy danych szeregów czasowych. W niniejszej pracy zbadano skuteczność metod analizy szeregów czasowych z wykorzystaniem danych modelowanych znaną funkcją wykładniczą z nałożonym szumem losowym. Takie podejście pozwala na kontrolowanie głównego trendu w danych przy jednoczesnym wprowadzeniu zmienności typowej dla danych rzeczywistych. Do budowy zależności zostały napisane skrypty. Podanajest graficzna interpretacja wyników.

20

Sustainability of a hydraulic facility and flood risk of its downstream section: the case of the Foum El-Gherza dam (Ziban east, Algeria)

Zakarya Maou, Bougherara Ahmed, Habibi Yahyaoui

Geomatics, Landmanagement and Landscape

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2023

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no. 2

7--22

EN

Due to advanced silting, the Foum El-Gherza dam has lost more than two thirds of its initial capacity (47 hm3) and is no longer able to withstand the floods that threaten its downstream section. Indeed, the damage recorded in recent years has confirmed the vulnerability of the man-made structures located on both banks of the Oued Labiod. Thus, we believe that the hydrological behaviour of the catchment area is no longer influenced by the dam. Therefore, the hydrological study involved a critical analysis (homogeneity tests) of the hydro-climatic data in order to highlight the characteristics of the historical events recorded during the period 1950–2019. The frequency study of the maximum daily rainfall and floods recorded at the dam allowed us to determine the rainfall and flow rates of the return periods (10, 25, 50, 100, 500 and 1000 years). The flooding of the 28 October 2011 were used as a standard for the calibration of the model calculated by the HEC-Ras software. After validation of the model, a prediction of the water levels and flood extent was made for the selected return periods. The results obtained show that a part of the town of Seryana (district located on the edge of the right bank) suffers from flooding proportionally to the return periods of the floods. In addition, some agricultural areas bordering the Oued are also affected by the floodings. The hazard modelling maps can be considered as a basis for a flood risk prevention plan (PPRI) and as a decision support tool.