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1

The analysis of the different modeling in CST for predicting designs of a monostatic and bistatic RCS

Bekimetov Alisher Farxodovich, Yangibaeva Madina

Diagnostyka

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2023

|

Vol. 24, No. 3

art. no. 2023308

EN

In this, research paper, we analyzed different radar cross-sections and models in Computer Simulation Technology (CST) software and tell in advance the RCS of the layer. In this variation exploration and representation of antenna layout in CST, we make a decision on various polarized plane wave angles. The research results may influence aircraft and any vehicle building, connecting with the incorporation of magnetic and electrical part power going return, therefore the polarization of plane waves, the use of different materials, aircraft, and any vehicle size. For this article, a microstrip antenna design with a reduced monostatic (RCS) with changing angle is described. Radar recognizes a reflected signal from this target due to microwave sensors' capacity to adequately light it with energy. The research used several both basic and sophisticated targets at an unaccompanied median rate of occurrence. Two categories of target forms, basic and complicated, made of iron material, give an appearance for assessing RCS in two distinct systems, Monostatic and Bistatic, with a range of angles.

2

Resolution in the 3D modeling of objects for additive manufacturing and reverse engineering – shutter effect

Coutiño-Moreno Elvis, Estrada Quirino, Maldonado-Onofre Daniel, Rodriguez-Mendez Alejandro, Gomez-Giron Julio

Applied Computer Science

|

2021

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Vol. 17, no 1

40--52

EN

This article presents a proportional relationship between Shutter and the value of the resolution scanning system that allows decision making for modeling 3D parts used in reverse engineering and additive manufacturing. As a first step, the object of interest is treated to dim excessive brightness, then the object is scanned (by point cloud or mesh) with the use of a Handyscan 700 scanner. The point cloud is processed with the Geomagic software Desing X to generate a CAD image and a “.stl” file for 3D printing.

3

Refleksyjne odbicie architektury – synteza wody i dzieła architektonicznego

Twardowski M., Żabicka A.

Środowisko Mieszkaniowe

|

2018

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nr 24

168--178

PL

Odkąd architektura towarzyszy człowiekowi, woda ma poważny wpływ na jej charakter. Pomijając budowle inżynierskie, w których woda jest głównym aktorem, w wielu przypadkach woda stanowi niezwykłe uzupełnienie budowli, które niejednokrotnie bez niej nie miałyby już takie siły odbioru. To dzięki wodzie budowle często stają się dziełami sztuki. Podkreśla ona wyjątkowość, tworzy, często ze światłem i cieniem, tajemniczość budynku. W Południowej Ameryce znaleźć można wiele przykładów, które popierają powyższą tezę. Również w Europie znajdujemy budowle oparte na podobnej zasadzie. Nie należy zapominać tutaj, iż większość przykładów architekturze towarzyszy zieleń, jednym razem znajdując się w środku zielonego ogrodu a innym gdy zieleń przenika się z wnętrzem budynku. Wszystkie one mogą być inspiracją dla budynku zaprojektowanego w Krakowie przez MTWW Architekci. Woda podkreśla budowę odbiciami i refleksami. Zieleń pojawia się w środku i na zewnątrz sprawiając, że użytkownicy przez cały czas otoczeni są przez naturę.

EN

Since architecture accompanied people, water has a serious impact on its character. Apart from engineering buildings, in which water is the main actor, in many cases it is an extraordinary supplement to a building, which would often not have such power without it. Thanks to water buildings often become works of art. It emphasizes uniqueness, creates, often with light and shadow, the mystery of the building. There are many examples in South America that support this thesis. We find buildings based on a similar principles in Europe. It should not be forgotten that most of the examples were designed together with greenery, sometimes being in the middle of a green garden, another time the greenery interfuse with the interior. All of them can be an inspiration for a building designed in Krakow by MTWW Architekci. Water emphasizes architecture by reflections. Greenery appears in the interior as well as outside, making users surrounded by nature the whole way through.

4

Rotation, initial stress, gravity and electromagnetic field effect on P wave reflection from stress-free surface elastic half-space with voids under three thermoelastic models

Abo-Dahab S. M., Rida S. Z., Mohamed R. A., Kilany A. A.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 1

313--328

EN

The present paper is devoted to investigate the influence of the rotation, thermal field, initial stress, gravity field, electromagnetic and voids on the reflection of P wave under three models of generalized thermoelasticity: Classical and Dynamical coupled model (CD), Lord-Shulman model (LS), Green-Lindsay model (GL), The boundary conditions at stress-free thermally insulated surface are satisfied to obtain Algebraic system of four equations in the reflection coefficients of various reflected waves. It is shown that there exist four plane waves; P1, P2, P3 and P4. In addition, the reflection coefficients from insulated and isothermal stress-free surface for the incident P wave are obtained. Finally, numerical values of the complex modulus of the reflection coefficients are visualized graphically to display the effects of the rotation, initial stress, gravity field magnetic field, thermal relaxation times and voids parameters.

5

Reflection of plane waves from surface of a generalized thermo-viscoelastic porous solid half-space with impedance boundary conditions

Singh B.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 4

1483--1496

EN

A phenomenon of reflction of plane waves from a thermally insulated surface of a solid half-space is studied in context of Lord-Shulman theory of generalized thermo-viscoelasticity with voids. The governing equations of generalized thermo-viscoelastic medium with voids are specialized in x-z plane. The plane wave solution of these equations shows the existence of three coupled longitudinal waves and a shear vertical wave in a generalized thermo-viscoelastic medium with voids. For incident plane wave (longitudinal or shear), three coupled longitudinal waves and a shear vertical wave reflect back in the medium. The mechanical boundary conditions at free surface of solid half-space are considered as impedance boundary conditions, in which the shear force tractions are assumed to vary linearly with the tangential displacement components multiplied by the frequency. The impedance corresponds to the constant of proportionality. The appropriate potentials of incident and reflected waves in the half-space will satisfy the required impedance boundary conditions. A non-homogeneous system of four equations in the amplitude ratios of reflected waves is obtained. These amplitude ratios are functions of material parameters, impedance parameter, angle of incidence, thermal relaxation and speeds of plane waves. Using relevant material parameters for medium, the amplitude ratios are computed numerically and plotted against certain ranges of impedance parameter and the angle of incidence.

6

Propagation and reflection of plane waves in a rotating magneto-elastic fibre-reinforced semi space with surface stress

Roy I., Acharya D. P., Acharya S.

Mechanics and Mechanical Engineering

|

2018

|

Vol. 22, nr 4

939--957

EN

The present paper investigates the propagation of quasi longitudinal (qLD) and quasi transverse (qTD) waves in a magneto elastic fibre-reinforced rotating semi-infinite medium. Reflections of waves from the flat boundary with surface stress have been studied in details. The governing equations have been used to obtain the polynomial characteristic equation from which qLD and qTD wave velocities are found. It is observed that both the wave velocities depend upon the incident angle. After imposing the appropriate boundary conditions including surface stress the resultant amplitude ratios for the total displacements have been obtained. Numerically simulated results have been depicted graphically by displaying two and three dimensional graphs to highlight the influence of magnetic field, rotation, surface stress and fibre-reinforcing nature of the material medium on the propagation and reflection of plane waves.

7

Colorimeter based on color sensor

Snizhko D. V., Sushko O. A., Reshetnyak E. A., Shtofel D. H., Zyska T., Smolarz A., Mussabekov N., Kalizhanova A.

Przegląd Elektrotechniczny

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2017

|

R. 93, nr 5

96--101

EN

In this paper colorimeter based on color sensor is considered. The developed colorimeter experimental utilization is shown on example of detection Cu2+, Co2+ ions and Neutral Red indicator. Realized measurement optical system in the colorimeter supports operation with different types of sorbents, as possibility is shown an operation with silica, polyurethane foam and the indicator paper. Dynamic range of device at 12 bit per channel and well stability of characteristic are enough to work with fine reliability that is no more 0.7% for analyzed test systems.

PL

W artykule przedstawiono kolorymetr zbudowany z wykorzystaniem czujnika barwy. Przedstawiono wykorzystanie przedstawionego kolorymetry na przykładzie detekcji jonów Cu2+, Co2+ i neutralnego wskaźnika barwy czerwonej. Zrealizowany system optyczny kolorymetru umożliwia pracę z różnymi rodzajami sorbentów. Możliwości te pokazano z wykorzystaniem krzemionki, pianki poliuretanowej i papierka wskaźnikowego.

8

Reaction of plane waves from a rotating magneto-thermoelastic medium with two-temperature and initial stress under three theories

Othman M. I. A., Abo-Dahab S. M., Alsebaey O. N. S.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 2

217--232

EN

The model of the equations of generalized magneto-thermoelasticity in an isotropic elastic medium with two-temperature under the effect initial stress is established. The entire elastic medium is rotated with a uniform angular velocity. The formulation is applied under three theories of generalized thermoelasticity: Lord-Shulman, Green-Lindsay, as well as the coupled theory. The Harmonic function is used to obtain the exact expressions for the considered variables. Some particular cases are also discussed in the context of the problem. We introduce the equations of the velocity of p-wave, T-wave and SV-wave. The boundary conditions for mechanical and Maxwell’s stresses and thermal insulated or isothermal are applied to determine the reflection coefficients for p-wave, T-wave and SV-wave. Some new aspects are obtained of the reflection coefficients and displayed graphically and the new conclusions are presented. Comparisons are also made with the results predicted by different theories (CT, L-S, G-L) in the presence of rotation, initial stress, magnetic field, as well as, the two-temperature parameter on the reflection of generalized thermos-elastic waves.

9

Propagation and reflection of plane waves in a rotating magneto elastic fibre-reinforced semi space with surface stress

Roy I., Acharya D. P., Acharya S.

Mechanics and Mechanical Engineering

|

2017

|

Vol. 21, nr 4

1043--1061

EN

The present paper investigates the propagation of quasi longitudinal (qLD) and quasi transverse (qTD) waves in a magneto elastic fibre-reinforced rotating semi-in finite medium. Reflections of waves from the flat boundary with surface stress have been studied in details. The governing equations have been used to obtain the polynomial characteristic equation from which qLD and qTD wave velocities are found. It is observed that both the wave velocities depend upon the incident angle. After imposing the appropriate boundary conditions including surface stress the resultant amplitude ratios for the total displacements have been obtained. Numerically simulated results have been depicted graphically by displaying two and three dimensional graphs to highlight the in uence of magnetic field, rotation, surface stress and fibre-reinforcing nature of the material medium on the propagation and reflection of plane waves.

10

On generalized magneto-thermoelastic P-, T- and SV-waves propagation at the interface between two magnetized solid-liquid media with initial stress

Abo-Dahab S. M.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 4

897--917

EN

In this paper, we study the effects of magnetic field and initial stress on plane waves propagation. We have investigated the problem of reflection and refraction of thermoelastic waves at a magnetized solid-liquid interface in the presence of initial stress, in the context of CT (Classical theory) of thermoelasticity, the problem has been solved. The boundary conditions applied at the interface are: (i) continuity of the displacement, (ii) vanishing of the tangential displacement, (iii) continuity of normal force per unit initial area, (iv) vanishing of the tangential stress and (v) continuity of temperature. The amplitudes ratios for the incident P-, T-, and SV- waves have been obtained. The reflection and transmission coefficients for the incident waves are computed numerically, considering the initial stress and magnetic field effects and the results are represented graphically.

11

Oblique water wave diffraction by a step

Dolai P.

International Journal of Applied Mechanics and Engineering

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2017

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Vol. 22, no. 1

35--47

EN

This paper is concerned with the problem of diffraction of an obliquely incident surface water wave train on an obstacle in the form of a finite step. Havelock expansions of water wave potentials are used in the mathematical analysis to obtain the physical parameters reflection and transmission coefficients in terms of integrals. Appropriate multi-term Galerkin approximations involving ultraspherical Gegenbauer polynomials are utilized to obtain a very accurate numerical estimate for reflection and transmission coefficients which are depicted graphically. From these figures various interesting results are discussed.

12

The proposal of the laboratories for calibration of radar level gauges

Mikuś P., Harťanský R., Smieško V.

Przegląd Elektrotechniczny

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2016

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R. 92, nr 2

72--74

EN

This article deals with the problem of the design of the measuring environment for the testing of the devices working on the base of the electromagnetic waves. We mean by these devices the radar level gauges. The radar level gauge is a source of the electromagnetic waves. The input part of this device receives reflected waves from the referential interface (reflection board). In the measuring environment can occur also various steel installations, e.g. constructions which consist of cylindrical steel beams. If the measuring environment contains steel installations, the receiving of the electromagnetic waves can be influenced by high frequency phenomena on the construction. In this article we focus on the proposal of the dimensions of the measuring environment.

PL

Artykuł dotyczy problemu projektowania stanowiska pomiarowego do badania urządzeń wykorzystujących fale elektromagnetyczne. Pod pojęciem tych urządzeń rozumie się radarowe wskaźniki poziomu. Radarowy wskaźnik poziomu jest źródłem fal elektromagnetycznych. Wejściowy element tego urządzenia odbiera fale odbite od płaszczyzny odniesienia. W środowisku pomiarowym mogą występować różne instalacje stalowe, np. elementy konstrukcyjne złożone z cylindrycznych stalowych belek. Jeżeli środowisko pomiarowe zawiera stalowe instalacje, odbiór fal elektromagnetycznych może być zakłócany wskutek zachodzących zjawisk wysokoczęstotliwościowych. W artykule skupiono się na propozycji określenia wymiarów środowiska pomiarowego.

13

Isometries in Teaching Descriptive Geometry and Engineering Graphics

Ulasevich Z., Ulasevich V.

Journal Biuletyn of Polish Society for Geometry and Engineering Graphics

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2016

|

Vol. 29

23--30

EN

Important basic transformations, implemented in CAD systems, are congruence transformations, so-called isometries, which preserve the distance of points. Logic of CAD software bases on the reflection, translation, rotation, and similarity. This fact is the important desideratum in the teaching of Descriptive Geometry. The paper includes a proposal for a teaching from the scope of isometries on the plane and in three-dimensional space.

PL

Ważnymi przekształceniami zaimplementowanymi w oprogramowaniu CAD, są izometrie, czyli przekształcenia zachowujące odległość punktów. Logika tych systemów opiera się gównie na pojęciu symetrii, translacji i obrotu. Ważną jeszcze rolę odgrywa podobieństwo. Uwzględnienie tego faktu w nauczaniu geometrii wykreślnej jest ważnym dezyderatem dydaktycznym. Praca zawiera propozycję dydaktyczną z zakresu zastosowania izometrii na płaszczyźnie i w przestrzeni.

14

Propagation of plane waves in a rotating transversely isotropic two temperature generalized thermoelastic solid half-space with voids

Bijarnia R., Singh B.

International Journal of Applied Mechanics and Engineering

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2016

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Vol. 21, no. 2

285--301

EN

The paper is concerned with the propagation of plane waves in a transversely isotropic two temperature generalized thermoelastic solid half-space with voids and rotation. The governing equations are modified in the context of Lord and Shulman theory of generalized thermoelasticity and solved to show the existence of four plane waves in the x – z plane. Reflection of these plane waves from thermally insulated stress free surface is also studied to obtain a system of four non-homogeneous equations. For numerical computations of speed and reflection coefficients, a particular material is modelled as transversely isotropic generalized thermoelastic solid half-space. The speeds of plane waves are computed against the angle of propagation to observe the effects of two temperature and rotation. Reflection coefficients of various reflected waves are also computed against the angle of incidence to observe the effects of various parameters.

15

Terahertz range double direction isolator based on stratified antiferromagneticdielectric structures : theoretical investigation

Vytovtov K., Hnatushenko V., Zouhdi S.

Elektronika : konstrukcje, technologie, zastosowania

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2015

|

Vol. 56, nr 2

75-78

EN

A double direction isolator based on a stratified antiferromagnetic-dielectric structure is proposed in the paper. Frequency dependence of the reflection coefficient on the incident angle and the anisotropy axis orientation is investigated analytically as the key feature of the isolator. Instead of well-known Faraday effect, we use strongly nonlinear frequency dispersion of the structure response to achieve desired non-reciprocal performance. It is shown that proposed isolator provides directional isolation of the incident plane wave at two frequencies of 0.55 THz and 1.65 THz with the half-power level bandwidths of 0.16 THz and 0.22 THz, respectively. Tuning of the isolator operating frequencies is the second issue solved in the paper. Frequency tuning is realized by a changing of external magnetic field. Both fine and broadband frequency tuning are demonstrated.

PL

Dwukierunkowy izolator pracujący w paśmie terahercowym, wykorzystujący antyferromagnetyczne, warstwowe struktury dielektryczne, przedstawiony jest w artykule. Charakterystyka częstotliwościowa współczynnika odbicia w zależności od kąta padania fali i orientacji osi anizotropii została przeanalizowana jako podstawowy parametr izolatora. Zamiast dobrze znanego efektu Faradaya wykorzystano fakt silnego rozproszenia częstotliwości odpowiedzi do analizy zachowania struktury izolatora. Wykazano, że proponowany izolator zapewnia izolację kierunkową dla dwóch częstotliwości 0,55 THz i 1,65 THz przy szerokości pasma 0,16 THz i 0,22 THz odpowiadającej mocy połówkowej. Przestrajanie częstotliwości pracy izolatora jest drugim zagadnieniem analizowanym w tej pracy. Przestrajanie częstotliwości pracy realizowane jest za pomocą zewnętrznego pola magnetycznego. Przedstawione zostały charakterystyki przestrajania izolatora.

16

Investigation of the reflective properties of layered antiferromagnetic-dielectric structures

Vytovtov K., Arkhipov A., Gnatushenko V.

Elektronika : konstrukcje, technologie, zastosowania

|

2014

|

Vol. 55, nr 2

55-58

EN

Reflection properties of layered antiferromagnetic-dielectric structures with an oblique axis orientation and an oblique planar wave falling are investigated in this paper. Nonreciprocal angle dependence in oblique axis orientation was obtained and described. Founded properties are based not on the Faraday effect but on the non-reciprocity of anisotropic material - FeF2 antiferromagnetic. Obtained result were studied in terahertz region but may be used in near-infrared region and radio frequency region with another anisotropic materials using. Obtained results allow us to propose a valve based on the investigated structure.

PL

Właściwości odbijające warstwowych antyferromagnetyczno-dielektrycznych struktur z ukośną orientacją osi i ukośną, płaską falą padania są badane w tej pracy. Uzyskano i opisano zależność kąta w orientacji skośnej osi. Założone właściwości nie są oparte na efekcie Faradaya, ale na braku wzajemności materiału anizotropowego-antyferromagnetycznego FeF2. Otrzymany wynik oceniano w obszarze terahercowym ale może być stosowany w obszarze bliskiej podczerwieni i w obszarze częstotliwości radiowych w odniesieniu do innych materiałów anizotropowych.

17

Reflection of waves in initially stressed transversely isotropic fibre-reinforced thermoelastic medium

Gupta R. R., Gupta R. R.

International Journal of Applied Mechanics and Engineering

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2013

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Vol. 18, no. 3

671--685

EN

The present investigation deals with the reflection of plane periodic waves incident at the surface of a homogeneous initially stressed transversely isotropic fibrereinforced thermoelastic medium. The wave equations are solved by imposing proper conditions on displacements, stresses and temperature distribution. Numerically simulated results have been depicted graphically for different angles of incidence with respect to frequency. Some special cases of interest have also been deduced from the present investigation.

18

Reflection of magneto-thermo-elastic waves from a rotating elastic half-space in generalized thermoelasticity under three theories

Othman M. I. A., Song Y.

Mechanics and Mechanical Engineering

|

2011

|

Vol. 15, nr 1

5-24

EN

The model of the equations of generalized magneto-thermoelasticity based on Lord-Shulman theory (LS) with one relaxation time, Green-Lindsay theory (GL) with two relaxation times, as well as the classical dynamical coupled theory (CD), is used to study the electro-magneto-thermoplastic interactions in a semi-infinite perfectly conducting solid. The entire elastic medium is rotating with a uniform angular velocity. There an initial magnetic field acts parallel to the plane boundary of the half-space. Reflection of magneto-thermoplastic waves under generalized thermoelasticity theory is employed to study the reflection of plane harmonic waves from a semi-infinite rotating elastic solid in a vacuum. The expressions for the reflection coefficients, which are the relations of the amplitudes of the reflected waves to the amplitude of the incident waves, are obtained. Similarly, the reflection coefficients ratios variation with the angle of incident under different conditions are shown graphically. Comparisons are made with the results predicted by the three theories in the presence and absence of rotation.

19

Kalibracja spektrofotometryczna modelu sondy odbiciowej do dynamicznego pomiaru wilgotności gleby

Wojciechowski T., Piechnik L.

Inżynieria Rolnicza

|

2010

|

R. 14, nr 2

285-292

PL

Upowszechnienie systemów rolnictwa precyzyjnego ograniczane jest przez brak lub małą dostępność wydajnych dynamicznych metod monitorowania środowiska glebowego. Rolę odegrać może tutaj zastosowanie metody odbiciowej pomiaru wilgotności gleb. W ramach prowadzonych działań opracowano metodykę dynamicznego pomiaru wilgotności gleby metodą odbiciową oraz sformułowano założenia i skonstruowano miernik z komercyjnym czujnikiem odbiciowym. Przeprowadzono badania spektrofotometryczne w zakresie NIR co pozwoliło na określenie długości fal najsilniej skorelowanych z wilgotnością gleb oraz ich porównanie z operacyjną długością fali czujnika optoelektronicznego miernika.

EN

Popularisation of precise agriculture systems is limited by complete lack or low availability of efficient, dynamic methods for soil environment monitoring. Using a reflection method for soil humidity measurement may play a role here. In the scope of carried out works, the researchers developed a methodology for dynamic soil humidity measurement using the reflection method, formulated guidelines and designed a meter with commercial reflection sensor. Spectrophotometric tests in NIR range were carried out, allowing to determine wavelengths most strongly correlated with humidity of soils, and to compare them to an operating wavelength of sensor in an optoelectronic meter.

20

Effectiveness of Shielding Electromagnetic Radiation, and Assumptions for Designing the Multi-layer Structures of Textile Shielding Materials

Brzeziński S., Rybicki T., Malinowska G., Karbownik I., Rybicki E., Szugajew L.

Fibres & Textiles in Eastern Europe

|

2009

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Vol. 17, no. 1 (72)

60--65

EN

In many cases, to obtain the required extent of protection against electromagnetic radiation (EMR) emitted by operating electrical and electronic devices, it is not enough to use only shielding materials that non-transmit the radiation as a results of its reflection, but it is indispensable to use shields (materials) possessing the capability to reflect and absorb EMR at the same time. Depending on their practical use, such materials should be characterised by a high EMR absorption coefficient, even twice as high as their reflection coefficient within as wide a frequency band as possible. This paper presents assumptions for designing multi-layer textile-polymeric materials, the dominating feature of which that increases the shielding effectiveness consists in absorbing EMR as a result of so-called multiple internal reflection. Methods for testing the coefficients of reflection and transmission as well as the preliminary assessment of the test results concerning the EMR shielding materials are also presented.

PL

W wielu przypadkach, celem uzyskania wymaganego stopnia ochrony przed promieniowaniem elektromagnetycznym (PEM), emitowanym przez pracujące urządzenia elektryczne i elektroniczne, niewystarczające jest zastosowanie tylko materiałów ekranujących „nieprzepuszczających” promieniowania w wyniku jego odbicia, ale niezbędne są ekrany (materiały) posiadające zdolność jednoczesnego odbijania i pochłaniania PEM. W zależności od przeznaczenia użytkowego, materiały takie powinny charakteryzować się dużym współczynnikiem absorpcji PEM, nawet dwukrotnie przekraczającym współczynnik odbicia i to w możliwie szerokim paśmie częstotliwości. W artykule przedstawiono założenia do konstrukcji wielowarstwowych materiałów włókienno-tworzywowych, dla których dominującym czynnikiem zwiększającym skuteczność ekranowania jest absorpcja PEM w wyniku tzw. wielokrotnego wewnętrznego odbicia, metodykę badań współczynnika odbicia i współczynnika transmisji oraz ocenę wstępną wyników badań materiałów ekranujących PEM.