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1

Comparison Between Low-Carbon Steel and Galvanized Steel by Deep Drawing Under the Influence of Different Parameters

Abdullah Mostafa Adel, Abed Aseel Hamad, Mansor Khalida Kadhim

Management Systems in Production Engineering

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2025

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nr 2 (33)

163--170

EN

Deep drawing is used to make a lot of different shapes. The purpose of this paper is to evaluate the thickness alteration behavior of deep-drawn cylindrical cups with dimensions (41.5 mm) and high (30 mm) under the influence of diverse factors such as the radius of the die’s (Rd = 9, 6.3 mm), velocity (v = 100, 300, 500 mm/min), thickness (to = 0.7, 0.5 mm), and the kind of metals used (L.c. steel and G. steel). ANSYS Workbench 21.0 software was used to implement the numerical simulation process, followed by constructing a cylindrical cup. The results reveal the highest thinning thickness (10.062% FEA, 15.626% EXP) in the curve area of the cup with low-carbon steel (to = 0.7 mm), while growth in punch speed and a decrease in the radius of the die results in higher thinning. The findings revealed a good agreement between experimental and numerical work, with the highest discrepancy being 5%. The galvanized steel metal demonstrated superiority in the cup’s curve region, where the thinning rate was less than 2.35% compared to the low-carbon steel. Working with smaller radii makes the cup break while working with larger radii makes it wrinkle more. So, intermediate radii, which are four to ten times the width of the piece, need to be worked.

2

Modelling of dynamic processes in a nonholonomic system in the form of Gibbs-Appell equations on the example of a ball mill

Shatokhin Volodymyr, Ivanchuk Yaroslav, Liman Vitaly, Komar Sergii, Kozlovskyi Oleksii

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2025

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T. 15, nr 4

32--38

EN

n the article the actual scientific and practical problem of creation of the universal mathematical model of dynamic processes in the shockless model of the ball mill is solved. This allowed to determinethe technological qualities of the device and to make an effective choice of its rational parameters. Computational studies have been carried out using the developed model by means of computer calculations. As a result, important regularitiesof the influence of parameters on the technological indicators of the technological device have been established. The result of the studyis the first development of a nonholonomic mathematical model of dynamic processes in a ball mill, presented in the form of Gibbs-Appellequations. It is shown that the calculation of the acceleration energy and the formulation of the equations of motion are significantly simplified when quasi-accelerations are used instead of generalised acceleration equations. The developed mathematical model allows to calculate the trajectories of the contact point of the ball with the surface of the spherical chamber, the compressive forces of interaction with the surface of the shell. The results of themathematical modelling allow efficient selection of rational parameters of the process equipment from the technological point of view.

PL

W artykule rozwiązano aktualny problem naukowy i praktyczny dotyczący stworzenia uniwersalnego modelu matematycznego procesówdynamicznych w bezuderzeniowym modelu młyna kulowego. Pozwoliło to określić właściwości technologiczne urządzenia i dokonać skutecznego wyboru jego racjonalnych parametrów. Przeprowadzono badania obliczeniowe z wykorzystaniem opracowanego modelu za pomocą obliczeń komputerowych.W rezultacie ustalono istotne prawidłowości wpływu parametrów na wskaźniki technologiczne urządzenia technologicznego. Wynikiem badań jest pierwsze opracowanie nieholonomicznego modelu matematycznego procesów dynamicznych w młynie kulowym, przedstawionego w postaci równań Gibbsa-Appella. Wykazano, że obliczenia energii przyspieszenia i sformułowanie równań ruchu są znacznie uproszczone, gdy zamiast uogólnionych równań przyspieszenia stosuje się quasi-przyspieszenia. Opracowany model matematyczny pozwala obliczyć trajektorie punktu styku kulki z powierzchnią komory sferycznej oraz siły ściskające oddziaływania z powierzchnią powłoki. Wyniki modelowania matematycznego pozwalają na efektywny dobór racjonalnych parametrów urządzeń procesowych z technologicznego punktu widzenia.

3

The required amount of mine air passing through the emergency passage into the mine

Zapletal Pavel, Koudelková Jaroslava, Urbanec Vítězslav, Štemberka Martin, Pach Grzegorz, Różański Zenon, Niewiadomski Adam

Archives of Mining Sciences

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2025

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Vol. 70, no. 3

403--421

EN

In mines, providing proper ventilation during emergencies is a key aspect of ensuring safety and protecting human lives. In the case of indirect intervention by taking extreme measures (the closure of the entire mine using fire covers), it is necessary to ensure an emergency passage of miners to the surface providing a sufficient amount of mine air for them. The speed of the air must not exceed the limit for the safe passage of people, and must not cause unstable fan operation. The modelling of this problem in this case is carried out on a simplified ventilation network, in which two interconnected pits at a depth of 1000 m are displayed. The input data and limit values correspond to the valid legislation of the Czech Republic, but the resulting proposed methodology is universal and applicable to any mine or underground space that is artificially ventilated, and the parameters of the ventilation network are known. The issue of safety is always the main and key element of underground mining or underground work, and this article provides a model example of how to approach it even in the most difficult situations.

4

Turbulence intensity in the vortex settling tank

Krukowski Marcin, Rusjan Anna, Kiczko Adam, Siwicki Piotr, Kozioł Adam

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

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2024

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Nr 90 (tom 1)

131--144

EN

Experimental research was undertaken to investigate changes in flow velocity and turbulence intensity in a vortex settling tank as a result of increasing flow rate. Two studies were conducted for two different flow rates through the settling tank. The changes in the flow turbulence structure were analysed at two depths of the settling tank based on the measured instantaneous flow velocities. The instantaneous velocities were measured using a three-component acoustic Doppler velocity meter. Changes in values and distributions of velocity and turbulence intensity in the vortex settling tank were presented. It was observed that a twofold increase in flow caused an up to a threefold increase in the average flow velocity near the settling tank walls, a twofold increase in the turbulence intensity near the settling tank walls, and an increase in zones of local turbulence. In these zones, the increase in the gradient of turbulence intensity values is much greater than in the others. The zone of turbulence with maximum values occurs on the left side of the settling tank near the outlet deflector. The presented changes in the turbulence structure negatively affect the efficiency of the settling tank by increasing the values of velocity and turbulence intensity.

5

Solving the prevention of the formation of traffic jams in pipelines in the transportation of gases by the autoejection process

Gurbanov Abdulaga, Sardarova Ijabika

Nafta-Gaz

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2024

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R. 80, nr 4

252--256

EN

The article presents the application of autoejection process to ensure efficient operation of pipeline systems and gas separation installations when it is impossible to remove and utilize the condensate from the pipelines. Thus, in the suggested ejector, a single common stream is separated into two streams, i.e., an active and a passive stream, as opposed to two separate independent streams in existing ejection devices. As a result, we refer to such an ejection process as autoejection, or a self-ejection process. Such a procedure is run in the pipeline with the goal of blowing and dusting the liquid phase through the central high-velocity nozzle in circumstances of mass blocking and coating rather than expelling the liquid from the pipes. On the cross-sectional area of the belts, the velocity profiles of flows in laminar and turbulent regimes are known to differ greatly from one another. The adhesion forces acting from the tube's central axis outwards, towards its walls cause the flow rate to decrease. There is a cross-sectional interaction of flows in this mode, according to experimental studies of turbulent flows. As a result, compared to the laminar domain, the flow velocities in this regime are more equally distributed across the cross-section of the flow, and their values are roughly equal to the flow's average value. In this case, based on the dependences of the flow ∆p = f(W), it is known from the calculations and the table that at such velocity limits of the flows, the “braking” pressure (p0) of the liquid coating on the pipe walls corresponds to the maximum velocity of the central gas flow. The autoejection process can occur due to the difference between the static pressures. Unsaturated absorbent coatings can be blasted off the tube absorber's walls using this technique and blended back into the main gas stream. Gas-liquid autoejectors installed along the pipe absorber's length make it possible to use this method. The purpose and principles of autoejectors’ operation are considered and a perspective of their application in tube absorbers is noted.

PL

Artykuł prezentuje zastosowanie procesu automatycznego strumieniowania w celu zapewnienia efektywnej pracy systemów rurociągowych i instalacji separacji gazu, gdy niemożliwe jest usunięcie i wykorzystanie kondensatu z rurociągów. W związku z tym w sugerowanej strumienicy automatycznej pojedynczy wspólny strumień jest rozdzielany na dwa strumienie, czyli aktywny i pasywny, w przeciwieństwie do dwóch oddzielnych, niezależnych strumieni w istniejących urządzeniach strumieniowych. Taki proces strumieniowania nazywany jest automatycznym strumieniowaniem lub procesem samostrumieniowania. Procedura ta uruchamiana jest w rurociągu w celu przedmuchiwania i odpylania fazy ciekłej przez centralną dyszę o wysokiej prędkości w warunkach masowego blokowania i usuwania, a nie wypierania cieczy z rur. Wiadomo, że profile prędkości przepływów w reżimach laminarnym i turbulentnym w przekroju poprzecznym stref znacznie się od siebie różnią. Siły adhezji działające od centralnej osi rury na zewnątrz w kierunku jej ścian powodują spadek prędkości przepływu. Zgodnie z wynikami badań eksperymentalnych przepływów turbulentnych w tym trybie występuje interakcja przepływów w przekroju poprzecznym. W rezultacie, w porównaniu do domeny laminarnej, prędkości przepływu w tym reżimie są bardziej równomiernie rozłożone w przekroju przepływu, a ich wartości są mniej więcej równe średniej wartości przepływu. W tym przypadku, na podstawie zależności przepływu ∆p = f(W), wiadomo z obliczeń i tabeli, że przy takich granicach prędkości przepływów, „hamujące” ciśnienie (p0) powłoki cieczy na ścianach rurociągu odpowiada maksymalnej prędkości centralnego przepływu gazu. Proces automatycznego strumieniowania może zaistnieć dzięki różnicy między ciśnieniami statycznymi. Nienasycone powłoki absorbujące mogą być zdmuchiwane ze ścian absorbera rurociągu przy użyciu tej techniki i ponownie mieszane z głównym strumieniem gazu. Wykorzystanie tej metody jest możliwe dzięki zastosowaniu automatycznej strumienicy gazowo-cieczowej zainstalowanej wzdłuż absorbera rurociągu. Artykuł zawiera również rozważania dotyczące celu stosowania i zasad działania strumienic automatycznych, zwracając uwagę na ich zastosowania w absorberach rurociągowych.

6

Increasing efficiency of technological processes in oil production based on innovative rheotechnologies

Mammadova Yevgeniya V.

Nafta-Gaz

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2024

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R. 80, nr 8

488--494

EN

Numerous studies by various authors have been devoted to gas lift wells. The scientific literature has addressed issues of increasing production of both Newtonian and non-Newtonian oils. Despite these efforts, the efficiency of the gas lift method remains relatively low, necessisating novel approaches. One of the methods to increase the productivity of gas lift wells may be the use of innovative rheotechnologies. Rheotechnology laverages knowledge about the rheological properties of formation fluids to address specific technological problems. This paper describes studies of non-Newtonian oils, their rheological properties, and their impact on the technical and economic indicators of gas lift wells. The analysis showed that by studying the formation of the non-Newtonian structure of oil, it is possible to influence its relaxation properties, and thus obtain the movement of an abnormal oil (anomalous fluid), both in the bottom-hole zone of the well and in the lifting pipes. The results of experimental studies showed that viscoelastic crude oil flowing into the wellbore contains an increased volume of reservoir gas, which, along with the injected working agent, perform additional work in lifting gas-liquid mixtures to the surface. During gas lifting operations, phenomena such as breakthrough and slippage of the working agent can be observed. Addressing all these factors enables better control over gas lift well operations and, consequently, improves the efficiency of the tecnological processes.

PL

Wielu autorów poświęciło swoje prace tematyce odwiertów eksploatowanych z wykorzystaniem metody sprężonego gazu. W literaturze naukowej poruszono kwestie zwiększenia wydobycia zarówno ropy o właściwościach newtonowskich, jak i nienewtonowskich. Pomimo tych wysiłków wydajność metody z zastosowaniem sprężonego gazu pozostaje stosunkowo niska, co wymaga opracowania nowych rozwiązań. Jedną z metod zwiększenia wydajności odwiertów eksploatowanych za pomocą sprężonego gazu może być zastosowanie innowacyjnych technologii reologicznych. Technologia reologiczna wykorzystuje wiedzę o właściwościach reologicznych płynów złożowych do rozwiązywania konkretnych problemów technologicznych. W artykule opisano badania nad ropą o właściwościach nienewtonowskich, jej właściwościami reologicznymi oraz ich wpływem na wskaźniki techniczne i ekonomiczne odwiertów eksploatowanych metodą sprężonego gazu. Przeprowadzona analiza wykazała, że badając proces formowania się nienewtonowskiej struktury ropy naftowej można wpływać na jej właściwości relaksacyjne, a tym samym uzyskać ruch nietypowej ropy naftowej („cieczy anomalnej”), zarówno w strefie przyodwiertowej, jak i w rurach wydobywczych. Wyniki badań eksperymentalnych wykazały, że lepkosprężysta ropa naftowa wpływająca do odwiertu charakteryzuje się zwiększoną objętością gazu złożowego, który wraz z wtryskiwanym czynnikiem roboczym pomaga wypychać mieszaniny gazu i cieczy na powierzchnię. Podczas operacji z zastosowaniem gazodźwigu można zaobserwować zjawiska takie jak przebicie i poślizg czynnika roboczego. Uwzględnienie wszystkich tych czynników umożliwia lepszą kontrolę nad operacjami podnoszenia gazu, a w konsekwencji poprawia efektywność procesów technologicznych.

7

Pulsatile MHD flow of two immiscible nanofluids through a porous channel with slip effects

Medisetty Padma Devi, Suripeddi Srinivas, Badeti Satyanarayana, Kuppalapalle Vajravelu

International Journal of Applied Mechanics and Engineering

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2024

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Vol. 29, no. 1

105--129

EN

The present study is carried out to investigate the effects of shape factor nanoparticles on the oscillatory MHD flow of a nanofluid in two immiscible liquids in a horizontal porous channel with velocity and thermal slip on the walls. Thermal radiation, Joule heating, viscous and Darcy dissipations have been accounted for in the model. We have considered and as nanoparticles, in the lower region (Region-I) and upper region (Region-II) respectively, with water as a base fluid. The effective ratio of thermal conductivity of the nanofluid is evaluated using the Maxwell-Garnetts model. Graphical behavior of velocity, temperature, and rate of heat transfer distributions have been depicted for the cases of slip and no-slip effects. This study has been made to understand the impact of different nanoparticle shape factors on temperature and heat transfer rate. For various parameters, values of shear stress distribution at the walls and the mass flux are shown in tabular form. Our study asserts that with the increase of the strength of the magnetic field, the velocity of the liquid falls and enhances the temperature of the liquid. The influence of different combinations of nanoparticles, on the flow variables, have also been discussed. In order to validate the analytical results, the numerical evaluation of the closed-form results, for the velocity distribution, has been compared with those of the numerical method, by using the NDSolve command in MATHEMATICA, and a good agreement is observed.

8

Modification of Axial Distribution of Fragment Velocity in Preformed Fragmentation Warheads

Li Xin, Wang Weili, Liang Zhengfeng, Dong Jun

Central European Journal of Energetic Materials

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2024

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Vol. 21, no. 1

22--52

EN

Fragment velocity is a crucial parameter for evaluating the destructive capability of a warhead, and it is typically calculated using the Gurney formula with corrections. The currently established correction formulas can determine the axial distribution of natural fragment velocity within the shell, but for a preformed fragmentation warhead, energy losses due to the existence of fragment gaps lead to calculated results that are larger than the actual values, making it unsuitable for accurate calculation of the axial distribution of fragment velocity in such warheads. This paper introduces a filling ratio correction function based on the concept of effective charge and establishes a calculation model for the axial distribution of fragment velocity in preformed fragmentation warheads. The numerical simulation method was validated using prototype ground static explosion test data, then the influence of key parameters such as charge diameter (d), length-diameter ratio (δ), and filling ratio (β) on the axial distribution of fragment velocity was investigated. The relationships between the three parameters (a, m, c) in the filling ratio correction function and the characteristic parameters were derived, and the filling ratio correction function and the calculation formula for the axial distribution of fragment velocity were fitted. Comparisons with existing empirical formulas indicate that the formulas established in this paper offer higher calculation accuracy, with an error of no more than 4.65% compared to measured values, and they can reliably determine the axial distribution of fragment velocity in preformed fragmentation warheads, providing significant practical application value.

9

Problematyka zapewnienia sprzężenia akustycznego głowic ultradźwiękowych kolejowego wagonu inspekcyjnego poruszającego się z prędkościami powyżej 80 km/h

Chałko Leszek, Antolik Łukasz, Machała Piotr, Uchroński Patryk

Badania Nieniszczące i Diagnostyka

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2024

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nr 3-4

35--41

PL

W referacie omówiono problematykę zapewnienia sprzężenia akustycznego i sposób rozwiązania w czasie realizacji projektu pt. „Innowacyjne rozwiązanie umożliwiające realizację badań defektoskopowych szyn przy prędkości od 60km/h do 120 km/h” związane z zapewnieniem odpowiedniego sprzężenia akustycznego głowic ultradźwiękowych. Przedstawiono konstrukcję stanowiska testowego oraz wyniki przeprowadzonych prób dynamicznych. Omówiono wyniki testów w zależności od prędkości, siły docisku, wydatku wody i sposobu jej dostarczenia do strefy współpracy bloku przetworników ultradźwiękowych z powierzchnią badanego przedmiotu.

EN

The paper refers the problems of acoustic coupling phenomena and their solutions during the implementation of the project entitled "Innovative solution for conducting rail defectoscopic tests at speeds from 60 km/h to 120 km/h" with the provision of an appropriate sound signal from the ultrasonic probes. The construction of test stand was presented as well as dynamic tests that were carried out. The test results depending on the speed, angle of attack (block frontal surface bend), water flow, method of water transfer in front of the blocks and block pressure power were discussed The concepts and tests results related to centralization of the probes in relation to the rail centre were described.

10

Experimental and pilot model research of spiral cyclone with curvilinear channels

Jakštoniene Inga, Paliulis Dainius, Venslovas Albertas, Plashykhin Sergii

Archives of Environmental Protection

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2024

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Vol. 50, no. 4

127--134

EN

The advanced type of cyclone was applied to separate wood particulate matter from the air. The cyclone was designed in the laboratory of Vilnius TECH. A series of experimental studies was conducted both in the lab and under industrial conditions. These studies aimed to specify the air velocity and aerodynamic resistance in the experimental and pilot six-channel cyclone with spiral casings and curvilinear semi-rings. Air treatment efficiency was also determined. The highest air treatment efficiency achieved using experimental cyclone was 91.4%, while the pilot cyclone achieved an efficiency of 94. 5%. The industrial and experimental cyclones were found to have similar air treatment efficiency.

11

Prędkości kosmiczne

Kindracki Jan

Postępy Fizyki

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2023

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T. 74, z. 2

24--28

PL

Ruch w przyrodzie jest wszechobecny, porusza się wszystko, co nas otacza począwszy od elektronów i protonów, aż po gwiazdy i galaktyki. Miarą prędkości jest droga pokonana przez dany obiekt (człowieka, samolot, cząstkę elementarną, . . . ) w jednostce czasu. A prędkość wydaje się być coraz bardziej istotna w coraz szybciej zmieniającym się świecie. Prędkość w kosmosie ma fundamentalne znaczenie, gdyż jest związana z trajektorią ruchu i możliwością realizacji danego celu. Określając prędkość zawsze definiujemy jakiś punkt odniesienia. W niniejszym krótkim artykule przedstawiono "kosmiczną” względność prędkości i jak ona wpływa na kosmiczne misje ludzkości. Nie da się ukryć, że stajemy się gatunkiem "kosmicznych wędrowców”, dla których zdobywanie kolejnych kosmicznych celów to sens istnienia. Księżyce Jowisza, księżyc Saturna Tytan, to nasze kolejne długofalowe cele, jednakże na drodze do ich realizacji w rozsądnym dla człowieka czasie stoi prędkość, którą musimy koniecznie zwiększyć.

EN

Movement in nature is ubiquitous. Everything around us moves, from electrons and protons to stars and galaxies. By definition, velocity is the distance traveled by a given object (human, plane, elementary particle, . . . ) in a time unit. And velocity seems to be more and more important in a quick-changing world. Velocity in the universe is crucial because it is related to the trajectory of movement and the possibility of achieving a given goal. When determining velocity, we always define a reference point. This paper explores the “cosmic” relativity of velocity and how it affects humanity’s space missions. Undoubtedly we are becoming “space wanderers”, for whom reaching further space goals has become the essence of life. Jupiter’s moons, Saturn’s moon Titan are our next long-term goals, but there is speed in the way of achieving these goals in a reasonable time for human. In order to achieve further ambitious goals, we need to increase the available travel velocity.

12

(Nie)oczywiste zastosowanie wideorejestratora drogowego

Maciąg Klaudia, Leń Przemysław, Maciąg Michał

Przegląd Geodezyjny

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2022

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R. 94, nr 10

40--44

PL

Podstawową funkcją wideorejestratorów drogowych jest utrwalanie obrazu potencjalnych zdarzeń drogowych celem umożliwienia ustalenia ich przyczyn i przebiegu. Rola tzw. czarnej skrzynki nie stanowi jednak jedynego zastosowania urządzenia. Wykorzystanie kamery samochodowej wyposażonej w moduł GNSS oraz darmowego oprogramowania i otwartych danych przestrzennych umożliwia przeprowadzenie szczegółowej analizy charakterystyki przebytej trasy oraz stylu jazdy kierowcy. W publikacji zaprezentowano autorskie algorytmy zapewniające m.in. możliwość automatycznego obliczenia parametrów ruchu, kontroli prędkości jazdy oraz wygenerowania prognozy wysokości mandatów karnych w przypadku przekroczenia dopuszczalnej prędkości w zasięgu pracy napotkanych fotoradarów. Intuicyjność obsługi stworzonych narzędzi czyni je dostępnymi dla przeciętnego użytkownika posiadającego podstawowe umiejętności w zakresie pracy w programie QGIS.

EN

The basic facility of the dash-cams is to record the potential road accident video for the purpose of identifying its cause and course. However, the role of a black box is not an only application of the device. The implementation of a dash-cam featuring a GNSS module with free software and open spatial data enables to conduct a detailed analysis of the route course and the driver's behaviour. The paper describes the authors' own algorithms providing i.a. automatic computation of the motion parameters, verification of the driving velocity and generating a forecast of potential fines in case of exceeding the speed limit in an area controlled by a speed camera. The intuitiveness of the created tools makes them available for an average user that has got an ability to use the QGIS software on a basic level.

13

Ruch pęcherzyka w cieczach i fizykochemiczna metoda detekcji zanieczyszczeń powierzchniowo-aktywnych w wodzie

Zawała Jan, Kosior Dominik, Małysa kazimierz

Wiadomości Chemiczne

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2021

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[Z] 75, 9-10

1317--1342

EN

Motion of gas bubbles in aqueous phase (either clean water or solutions of surface-active substances) is a phenomenon of great practical importance. Gas/liquid contacting is one of the most common operations in the chemical and petrochemical industry and mineral processing In particular in mineral industry, for all kind of flotation processes it is the main act responsible for the success of the entire technology As a result, properties of the liquid/gas interfaces are considered as a one of the most important parameters, determining the outcome of industrial applications and engineering processes. These properties can be modified by surfactants which adsorption (molecules accumulation) at the interfaces leads to the decrease in the interfacial tension and modification of the hydrodynamic boundary conditions. Description of a single bubble motion in wide range of flow magnitude (Reynolds numbers) is not trivial and many attempts have been undertaken to quantify a bubble behavior in liquids. This paper presents a short overview of the current “state of arts” on physics of the bubble motion in liquids and the elaborated models, describing motion of the bubble formed in liquid phase. The comparison of the theoretical models predictions with the available experimental data is presented. It is shown, moreover, that the bubble velocity can be used as a very sensitive tool for detection of organic contaminations in environmental water samples.

14

Magistrala Siedlce-Bołogoje jako przykład kolei strategicznej

Massel Andrzej

Kwartalnik Historii Nauki i Techniki

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2021

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T. 66, nr 4

107--156

EN

The article presents a comprehensive view of the origins, technical characteristics and functioning of the Siedlce-Bologoye railway line. This railway, with an impressive length of 1.100 km, was built in the years 1902-1907 as a connection between the lands of the Kingdom of Poland and the governorates of central Russia in order to ensure the efficient transport of troops and their supplies given the anticipated war with Germany and Austria-Hungary. The work aims to illustrate to what extent the assumptions of the construction promoters were confirmed and how it was used in particular periods.

15

Flow characteristics after installation of floating bridge in open channel

Ibrahim Mohamed M., Eltoukhy Mahmoud A.R., Ghanim Adnan D.

Journal of Water and Land Development

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2021

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no. 49

244--251

EN

A pontoon bridge, also known as a floating bridge, can be used as for pedestrian and vehicle traffic. The buoyancy of the floating bridge limits the maximum load it can carry. This research included experimental runs to study variations of open channel flow characteristics upstream and downstream a floating bridge. Eighty one runs have been carried out using a flume in a hydraulic laboratory. The experimental run program is classified into two main categories; the first investigates the velocity ratios (vds/vus) downstream and upstream the floating bridge. The second category is concerned with the energy head losses (hL) due to the presence of a floating bridge. The experimental runs are carried out using three pontoon lengths, three flow depths, six submerged depths, and three discharges. The results are analysed and graphically presented to help predict hydraulic parameters. The outcomes have shown that the floating bridge upstream, Froude number and submergence of the pontoon are the dominant parameters that affect the studied flow characteristics.

16

Mathematical modelling of water-based Fe3O4 nanofluid due to rotating disc and comparison with similarity solution

Bhandari Anupam

Acta Mechanica et Automatica

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2021

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Vol. 15, no. 3

113--121

EN

The current research demonstrates the revolving flow of water-based Fe3O4 nanofluid due to the uniform rotation of the disc. This flow of nanofluid is investigated using CFD Module in COMSOL Multiphysics. However, the similarity solution for this flow is also ob-tained after transforming the given equation into a non-dimensional form. In the CFD Module, streamlines and surface plots are compared with the similarity solution for the magnitude of the velocity, radial velocity, tangential velocity, and axial velocity. The results from the direct simulation in the CFD Module and the solution of dimensionless equations represent a similar solution of velocity distribution. The derived results show that increasing the volume concentration of nanoparticles and effective magnetic parameters decrease the velocity distribu-tion in the flow. Results in the CFD Module are important for monitoring the real-time particle tracing in the flow and, on the other hand, the dimensionless solution is also significant for the physical interpretation of the problem. Both methods of solution empower each other and present the physical model without sacrificing the relevant physical phenomena.

17

Characterization of amplitude scintillation and distribution of positioning error for IRNSS/GPS/SBAS receiver

Prajapati Mitchell, Rawat Abhishek, Sharma Shivam

Acta Geophysica

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2021

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Vol. 69, no. 1

323--333

EN

Indian regional navigation satellite system (IRNSS) or Navigation with Indian Constellation (NaVIC) is the satellite-based navigation system, established and controlled by the Indian Space Research Organization. It provides services of positioning, velocity, and timing for civilian and military applications. Ionospheric irregularities cause the fuctuations in the amplitude and phase of the received navigation signals; this phenomenon is known as scintillation. Scintillation can create the error in precise positioning and degrades the position accuracy of the navigation system. It varies with solar activity, geographical location, seasonal variation, day–night time, and elevation angle of satellites. The S4 index is one of the key parameters to estimate the amplitude scintillation to recognize the quality of the navigation signal. In this paper, amplitude scintillation characteristics are studied with IRNSS/GPS/SBAS in the Ahmedabad region which is at the average altitude of 53 m. S4 index is calculated and analyzed using the real-time navigation data of one week. Here, IRNSS/GPS/SBAS receiver with L1, L5, and S-band, is used to collect the data at low altitude station (IITRAM, Ahmedabad). The position error of normal sunny days is calculated using IRNSS/GPS/SBAS receiver. The probability of position error is also derived and found that it follows the gamma distribution function and validate it statistically using a chi-square test. This study also focuses on the efect of elevation of the satellite on the value of carrier to noise ratio at the location of IITRAM.

18

The effects of ArUco marker velocity and size on motion capture detection and accuracy in the context of human body kinematics analysis

Wieczorek Bartosz, Warguła Łukasz, Kukla Mateusz, Kubacki Arkadiusz, Górecki Jan

Technical Transactions

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2020

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Vol. 117, iss. 1

art. no. e2020036

EN

The research aim was to analyse the influence of velocity and size of markers on the accuracy of motion capture measurement utilising image processing with the use of OpenCV. On the basis of the obtained results, the usefulness of the applied measurement method in studying the kinematics of the human body while driving operating a wheelchair was determined. This article presents the test results for a low-budget motion capture measurement system for testing the kinematics of the human body in a single plane. The tested measuring system includes a standard activity camera Xiaomi Yi4K, expanded polystyrene markers with printed ArUco codes, and original software for marker position detection developed by the author. The analysis of the measurement method with regard to its applicability in biomechanical studies has highlighted several key factors: the number of measuring points, measurement accuracy expressed as a relative error and the limit velocity at which the marker trajectory is correctly represented. The article shows that the limit velocity of the marker is 2.2 m/s for 50x50 mm markers and 1.4 m/s for 30x30 mm markers. The number of measured points ranged from 233 to 2,457 depending on the marker velocity. The relative error did not exceed 5% for the marker velocities and thus provided a correct representation of its trajectory.

19

Określanie prędkości pojazdów na podstawie materiału wideo. Cz. 2

Kosendiak Tomasz

Paragraf na Drodze

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2020

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Nr 1

41--50

PL

Filmy wykonywane przy użyciu automatycznych, stacjonarnych i mobilnych rejestratorów coraz częściej są materiałem służącym do rekonstrukcji wypadku drogowego. Celem tego artykułu jest przedstawienie sposobu postępowania dla ustalenia prędkości pojazdu wymijającego się z pojazdem wyposażonym w kamerę wideo.

EN

Films made with automatic, stationary and mobile recorders are increasingly often used in road accident reconstruction. The aim of this article is to show how to accurately determine the speed of an oncoming vehicle equipped with a video recorder.

20

Major Features Of Adaptive Supply Chains – Literature Review

Leończuk Dorota

Logistics and Transport

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2020

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Vol. 45-46, No. 1-2

43--53

EN

Adaptiveness is one of the most significant features of the supply chain that affects the results of its functioning. The capability of the supply chain to adapt to all, more and more demanding conditions is one of the main factors that guarantee long-term competitiveness and success. R. Kalakota, M. Robinson and P. Gundepudi consider inventory visibility, fulfilment velocity and coordination versatility as three fundamental pillars of adaptive supply chains, also termed as 3V in the literature. The chief objective of this paper is the identification of features that a supply chain should have in order to be called adaptive, as well as the verification of their compliance with the 3V principle. The review of the available literature sources that focus on the subject of the major features of adaptive supply chains (in particular having a decisive effect on their adaptive capabilities) has resulted in certain common elements. The authors of all the described approaches emphasise the two features: visibility and velocity. The third, frequently indicated, feature is also versatility or variety (that can be treated as one of the elements of the versatility of the supply chain). Visibility involves ensuring access to the information for all participants in the supply chain, also customers. Velocity, in turn, refers to the reaction time of the supply chain to all sorts of events and the time of implementing necessary changes. The third element is versatility. It primarily involves balancing the operational capability of a supply chain with market requirements, in particular delivering suitable products and services of the required quality and in the ordered volume. It is also vital to adjust the offer to the individual needs of customers.