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1

Lung divisions for models of cardiopulmonary interaction – preliminary tests

Pałko Krzysztof J., Kołodziej Dariusz, Darowski Marek

Polish Journal of Medical Physics and Engineering

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2024

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Vol. 30, Iss. 2

52--68

EN

Introduction: The perfusion of a part of the lung depends on its distance from the pulmonary trunk (differences in vascular resistance) and on the horizontal plane (differences in hydrostatic pressure). The aim of this study was to determine the geometric parameters characterising their positions and sizes in order to analyse the diffusion of the ventilation/perfusion ratio. Material and methods: A developed virtual respiratory system has been supplemented with an appropriate model of pulmonary circulation that uses a lung outline that is divided into parts based on an anatomical atlas and a CT image; it comprises a 3D geometric model of the lungs that was developed using the Inventor CAD software (Autodesk, Inc, San Francisco, USA). Each panel was divided into 2 horizontal and 8 vertical parts; the 16-part division was then modified. Results: When taking human lungs as a research object and simulating their accompanying physical, biological, or biochemical phenomena, one necessary task is to construct a spatial model of the lungs that takes into account, and maintains awareness of, the limitations of the source of data that is relied upon. The developed modified geometric model of lung division turned out to be useful and was successfully applied to a virtual patient, among others, as part of the VirRespir project. Conclusions: Finally, we can conclude that the virtual cardiorespiratory system thus elaborated may serve as a proper tool for the preliminary analysis of such complex interactions, considering the elaborated model of the lung’s divisions and its future improvements.

2

Optimising the geometric parameters of a gear in a tractor transmission under constraints using kisssoft

Can Emre, Bozca Mehmet

Acta Mechanica et Automatica

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2023

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Vol. 17, no. 2

145--159

EN

We optimise the speed gears in a tractor transmission with KISSsoft software under three constraints: input power torque, transmission system volume and the gear ratio for each speed. This study aimed to optimise the module, face width, gear quality, centre distance, number of teeth, helix angle, addendum modification coefficient and pressure angle for each speed while considering the above constraints based on an optimisation chart. Tooth bending stress, tooth contact stress, contact ratio and specific sliding were considered during optimisation. Additionally, the effects of changes in a module on the gear profiles, overlap ratio, number of teeth and weight of the gear pair were examined. Strength calculations of gear pairs that were optimised and defined for all geometric parameters with KISSsoft were calculated with the mathematical model described in ISO 6336, and results were then compared. Finally, backlash was minimised for all gear pairs as defined with geometric parameters, and all dimensions and tolerances were determined for gear inspection after manufacturing. A concept design was also presented. We conclude that both the KISSsoft results and mathematical model results are within the range of the target value.

3

A computational analysis of different geometric ratios at the input of a secondary fluid that affects the efficiency of a subsonic air-air ejector

Hincapie-Montoya Jhon Fredy, Sierra-Del-Rio Jorge Andres, Torres-Lopez Edwar, Hincapie-Zuluaga Diego Andres

Engineering Transactions

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2021

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Vol. 69, iss. 3

257--269

EN

For this study, the computational fluid dynamics (CFD) technique was used to investigate the combined effects of different geometric parameter relationships; inclination angle variation of the secondary fluid inlet, different lengths of the mixing chamber, and different separation values between the nozzle outlet and the input of the mixing chamber, in an air-air ejector used in a subsonic regime. As a working fluid, the air was used as an ideal gas and its viscosity was expressed as a constant both in the primary and secondary fluids. The renormalization group (RNG) κ−ε turbulence model was used to predict more accurately the way the pressure recovers along the ejector and suitability/applicability to for recirculation flows. It was found in the numerical results that there is an optimal value of the inclination angle for the secondary fluid inlet, the length of the mixing chamber and the separation between the nozzle outlet and the mixing chamber inlet, where the ejector obtains its maximum mass flow ratio. In addition, it was found that the efficiency of the air-air ejector is related to the inclination angle of the secondary fluid inlet.

4

Metodyka wyznaczania odkształceń mostu suwnicowego

Bryś Henryk, Ćmielewski Kazimierz

Przegląd Geodezyjny

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2020

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R. 92, nr 8

16--18

PL

W pracy przedstawiono zintegrowaną technologię wyznaczania geometrii odkształcenia mostu suwnicy w stanie statycznym z wykorzystaniem precyzyjnych tachimetrów elektronicznych o prospektowych parametrach technicznych S_α=0,15 mgon oraz S_D=0,5+1 ppm. Wyznaczone analitycznie parametry geometryczne (kąty i długości), pozwalają na precyzyjną interdyscyplinarną interpretację zaistniałych w czasie i przestrzeni zmian odkształceń.

EN

The paper presents the integrated technology for determining the geometry of the crane bridge deformation in a static state using precise electronic total stations with prospective technical parameters Sα = 0.15 mgon and SD = 0.5 + 1 ppm. Analytically determined geometrical parameters (angles and lengths) allow for precise interdisciplinary interpretation of deformations occurring in time and space.

5

Investigation of the Influence of Technology Parameters and Thread Type on Embroidered Textile Element Quality

Daukantienė Virginija, Mikelionytė Karolina

Autex Research Journal

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2020

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Vol. 20, no. 4

517--523

EN

Embroidery can be applied to improve esthetic or functional properties of products. However, the expected appearance of the original design may be discarded by unsuitable selected technological parameters of embroidery machine. Thus, the influence of the technological parameters and embroidery thread types on the embroidery geometric parameters and on tension characteristics of embroidery has been investigated in this research. The research results revealed that the changes in geometry parameters of the designed digital image compared with the ones of actual embroidery samples are dependent on embroidery filling type, stitch density, and thread type. Mechanical testing of the embroidery elements has proved that embroidering influences the decrease in material breaking force and elongation at break compared with their initial tension characteristics.

6

Integrated square shape inductor with magnetic core in a buck converter DC-DC

Namoune Abdelhadi, Taleb Rachid, Derrouazin Ahmed, Belboula Abdelkader, Hamid Azzedine

Przegląd Elektrotechniczny

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2019

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R. 95, nr 9

57--61

EN

This paper presents the buck converter DC-DC. At first, we define the characteristics of the converter. The second, we descript our inductor; the topology of square shape inductor has been presented to extract the geometric parameters. The equivalent electrical model approved of the integrated inductor with magnetic core takes into account all the technological parameters which are illustrated by analytic expressions. Moreover, the results of different simulations concern the effect of geometrical parameters of inductor on the inductance value and quality factor. Finely, we performed simulations on the operating of our buck converter including firstly an ideal inductor and then an integrated inductor with magnetic core. Simulation results have shown that the waveforms of the current and output voltage in both cases are similar.

PL

Zaprezentowano przekształtnik typu buck DC-DC wykorzystujący planarną indukcyjność. Przedstawiono analiz wpływu wymiarów dławika na parametry indukcyjności takie jak dobroć.

7

Integrated solenoid inductor with magnetic core in a buck converter

Namoune Abdelhadi, Taleb Rachid, Derrouazin Ahmed, Belboula Abdelkader

Przegląd Elektrotechniczny

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2019

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R. 95, nr 8

92--95

EN

In this paper, we discuss the design and modeling of a solenoid inductor with a magnetic core. The equivalent electrical model approved of the integrated solenoid inductor acquires into account the inductance and quality factor. The optimization of the inductance and quality factor values is based on the numerical analysis of the influence of the geometric parameters on the electrical characteristics of the solenoid inductor. The results simulation based on the MATLAB software. Finally, is discussing about the integrated solenoid inductor in a buck converter DC-DC, simulation results present by PSIM.

PL

Przedstawiono projekt planarnego scalonego dławika. Analizowano parametry geometryczne pod kątem najlepszej dobroci cewki. Podzespół może być zintegrowany z układem przekształtnika.

8

Analysis of variations in and correlations between selected physical parameters of common beech (Fagus silvatica L.) nuts

Kaliniewicz Z., Markowski P., Anders A., Tylek P., Krzysiak Z., Wasielewski W.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2018

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nr 21(1)

49--63

EN

The basic dimensions and the mass of common beech nuts and seeds from five nut batches, harvested from tree stands in northern Poland, were determined. Environmental conditions had a greater influence on seed plumpness than the age of tree stands. The results of measurements were analyzed statistically by analysis of variance, correlation analysis and linear regression analysis. Despite differences in their plumpness, nuts were characterized by nearly identical cross-sections which resembled an equilateral triangle. The thickness of nuts and seeds was highly correlated with their mass, and this information can facilitate seed husking and separation into mass categories. Before and after husking, seeds should be separated with the use of a mesh screen with longitudinal openings. Medium-sized (most numerous) seeds were separated into the following plumpness categories using a screen separator with ≠6 mm and ≠7 mm openings: 84% of moderately plump seeds, 3% of seeds with reduced plumpness, and 13% of plump seeds.

9

Calculation and Selection of Flat-Plate Solar Collector Geometric Parameters with Thermosiphon Circulation

Amirgaliyev Y., Kunelbayev M., Wójcik W., Amirgaliyev B., Kalizhanova A., Auelbekov O., Kataev N., Kozbakova A.

Journal of Ecological Engineering

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2018

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Vol. 19, nr 6

176--181

EN

The article describes a newly developed calculation technique and the choice of the geometrical parameters of the solar collector with the siphon effect. The dependence of the cross section of the pipe on the flow time for different values of the head is also shown. With an increase in the siphon head, the flow time of the liquid increases as well. This is explained by the fact that with increasing head, the hydraulic resistance of the siphon rises, which leads to a decrease in the velocity of the fluid. For the first time, a relationship determining the time of fluid outflow in dependence on the geometric parameters of the solar collector is formulated. The developed technique allowed to establish that the local hydraulic resistance and friction play a significant role in the heat carrier flow rate.

10

Research on the influence of geometric parameters on the phenomenon of snaking of articulated vehicles

Dudziński P., Skurjat A.

Zeszyty Naukowe / Wyższa Szkoła Oficerska Wojsk Lądowych im. gen. T. Kościuszki

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2017

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Nr 4

294--301

EN

The article presents the results of own numerical research conducted to determine the influence of the differential, causing the occurrence of the non-uniform torsion of wheels on the same axle and the changes in the width of an articulated vehicle, on the changes of the angle in the turn joint leading to snaking. An attempt was also made to determine the influence of swaying on vehicle stability. The quantitative influence of the above mentioned factors has been determined. Analytical formulae are also presented.

11

Oceny stanu frezu kulistego w zmiennych warunkach obróbki elementów trójwymiarowych

Wittbrodt P., Łapuńka I.

Stal, Metale & Nowe Technologie

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2017

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nr 9-10

26--30

PL

W artykule przedstawiono problemy oceny stanu frezu kulistego przy obróbce elementów trójwymiarowych. Przedstawiono wybrane metody oceny zużycia ostrzy narzędzia w zmiennych warunkach skrawania.

EN

The paper presents some problems related to the ball nose end mill wear estimation during milling three-dimensional elements. The selected methods of tool wear assessment in variable milling conditions are presented.

12

String sieve: design concept and parameters

Kaliniewicz Z.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2013

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nr 16(2)

119--129

EN

This paper presents the design concept and the parameters of a new device for cleaning and-or sorting seeds and grain produced in a conventional farm. The discussed device is a string sieve where the groove between adjacent strings is minimal at the beginning of the screen and increases towards the end of the screen. The proposed sieve poses an alternative to a screen separator comprising a set of differently-sized mesh screens with longitudinal openings. In view of the average size of farm-produced seeds, the width of the separating groove should be set at 1mm at the beginning of the screen and 11 mm at the end of the screen. In sieves not designed for grading large seeds or vetch seeds, the width of the separating groove can be set at 1 mm and 5 mm, respectively.

13

Electronic measurement system for monitoring of geometrical parameters of rolling shaped metal profiles

Zaharieva S., Mutkov V., Georgiev I.

Elektronika : konstrukcje, technologie, zastosowania

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2012

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Vol. 53, nr 1

95-98

EN

The measurement of the complex and the differential geometric parameters in the production process of cylindrical, square and rectangular rolling shaped metal profiles will inevitably lead to a rise in the production quality. The dynamism of the technological process and the influence of great number of outside factors over geometrical parameters of revolving, enforce development of an electronic measurement system, which reliably reads and preserves measured data immediately in the production process of rolling shaped metal. The accomplished electronic measurement system for monitoring of geometric parameters of rolling shaped metal performs an active firsthand control in the production process, for the purpose of management of the quality of the finished production.

PL

Pomiar kompleksowych i różnicowych geometrycznych parametrów w trakcie produkcji cylindrycznych, kwadratowych i prostokątnych wytłaczanych wyrobów niewątpliwie zwiększa jakość gotowej produkcji. Dynamika procesu technologicznego oraz wpływ zewnętrznych czynników na parametry wyrobów narzuca wprowadzanie elektronicznego systemu pomiarowego, który w trakcie produkcji mierzy i przechowywuje dane pomiarów. Zrealizowany elektroniczny system pomiarowy do kontroli parametrów geometrycznych profili produkowanych na liniach wytłaczakowych pozwala na aktywną kontrolę w trakcie produkcji i równocześnie zwiększa jakość gotowej produkcji.

14

Methods of geometric parameters estimation for a mechanism based on point coordinates measurements

Knapczyk J., Maniowski M.

Archive of Mechanical Engineering

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2009

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Vol. LVI, nr 3

291-301

EN

The paper presents selected methods used for estimation the unknown geometrical parameters of a spatial mechanism model, used to describe the position and orientation of the end-effector, for example the coordinates of the center points of spherical joints, link dimensions etc. These data are necessary when dealing with computer simulation of any mechanism. The parameters are estimated based on coordinate measurements of selected points, located on the real mechanism links, using a portable manipulator with serial structure composed of 6 revolute joints and a spherical probe, but other techniques of acquiring point coordinates are applicable as well. The described methods can be used in the cases of a disassembled link, an assembled mechanism and redundant data sets. This methods are characterized by accuracy and robustness in the presence of different levels of noise, stability with respect to degenerate data sets, and low computation time. Special attention is paid to the case when the wanted parameters are hard to measure directly. Numerical examples are presented dealing with 5-link mechanism used to guide front wheels of a car.

PL

W pracy przedstawiono metody estymacji położenia i przemieszczeń mechanizmu przestrzennego, na podstawie znanych współrzędnościowych wybranych punktów mechanizmu, które zmierzono metodą stykową za pomocą szeregowego manipulatora pomiarowego o 6 parach obrotowych. Opisano kolejne etapy pomiarów i estymacji, np.: pomiary punktów, osi, cylindrów i środków sfer, transformacje układów współrzędnych, miary rozrzutu pomiarów. Procedurę tę wykorzystano do wyznaczenia nieznanych parametrów geometrycznych mechanizmu oraz do weryfikacji jego modelu symulacyjnego. Przykład numeryczny dotyczy wielo-wahaczowego mechanizmu prowadzenia koła samochodu.

15

Analytical-numerical model for the detection of structural defects by lock-in thermography

Gralewicz G., Owczarek G., Więcek B.

Problemy Eksploatacji

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2006

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nr 2

65-79

EN

This paper presents the results of analytical-numerical modelling for the carbon-fibre-reinforced polymer (CFRP) structure using lock-in thermography. The method consists of the excitation of thermal effects in the tested structure caused by an external heat source. Simulations have been carried out to determine the optimum conditions for the lock-in evaluation in order to detect internal defects, measure their thickness and evaluate thermal properties. In the structure under study, a defect was simulated by inserting to the CFRP volume such materials as teflon and epoxy resin. Since many structures consist of CFRP, the rapid and remote identification of delaminations, impact damages and cracks is a topic of major concern. The results of our study indicate that a method is required for the maintenance of safety relevant structures (e.g. aerospace equipment and vehicles) where one needs to defect areas early enough to prevent catastrophic failure.

PL

W pracy przedstawiono wyniki modelowania analityczno-numerycznego dla struktury karbon-włókno-wzmocniony polimer (CFRP) wykorzystując metodę termografii synchronicznej (lock-in). Metoda ta polega na wymuszaniu przez zewnętrzne źródło ciepła zjawisk termicznych zachodzących w badanej strukturze. Przeprowadzone symulacje miały na celu określenie optymalnych warunków badań metodą lock-in, w celu wykrywania defektów wewnętrznych, dokonywania pomiaru grubości ich warstw, a także badania właściwości cieplnych. W analizowanej strukturze defekt był symulowany przez wprowadzenie do objętości CFRP takich materiałów, jak teflon i żywica epoksydowa. Wyniki przedstawione w pracy potwierdzają przydatność metody przy ocenie struktur materiałowych (wykorzystywanych w lotnictwie oraz przemyśle samochodowym), gdzie odpowiednio wcześnie wykryte defekty struktur mogą zapobiec groźnym wypadkom.

16

Weryfikacja metody skalowania parametrów geometryczno-wytrzymałosciowych na modelach wirtualnych.

Rutkowski J.

Mechanik

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2006

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R. 79, nr 10

822-825

PL

Metoda skalowania parametrów geometryczno-wytrzymałościowych została opracowana w związku z potrzebą skrócenia czasu przygotowania modelu i obliczeń optymalizacyjnych konstrukcji mechanicznych. Zaletą metody skalowania jest szybkość uzyskiwania wyników, którą osiąga się dzięki przyjętym uproszczeniom i przybliżeniom. Te ostatnie są jednak źródłem niedokładności obliczeniowych, które należało zbadać. W tym celu prowadzone są badania symulacyjne, których pierwszy etap już zakończono, a wyniki przedstawiono.

EN

Presented are the results of simulation exercise carried out for veryfication of the presumed theoretical method of scaling of the strength/geometric parameters.

17

Wpływ rozdzielczości i kompresji obrazu na błąd pomiaru geometrii oraz barwy ziarniaków zbóż

Zapotoczny P.

Inżynieria Rolnicza

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2005

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R. 9, nr 8

417--425

PL

Przedstawiono rozważania nad wpływem rozdzielczości i kompresji obrazu na pomiar geometrii ziarniaków zbóż. Obraz ziarniaków pozyskiwany był za pomocą aparatu cyfrowego, a automatyczny pomiar geometrii wykonany został przy użyciu programu MultiScan v. 11.06. Rozdzielczość i kompresja obrazu nie miały wpływu na pomiar pola powierzchni, natomiast pozostałe wymiary zmieniały się w zależności od rozdzielczości i kompresji.

EN

The study considered the influence of digital image resolution and compression on the measurements of cereal grain geometry. Grain image was obtained by using a digital camera. The automatic measurement of grain geometry was realized by application of the MultiScan v. 11.06 programme. Neither the image resolution nor compression did affect the exactness of grain surface measurement, whereas the other dimensions changed depending on the resolution and compression parameters.