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Публікація

Accurate investigation of coupled plasmonic resonances in a chain of silver nanowires

(IEEE, 2016) Stognii, N. P.; Sakhnenko, N. K.

This paper presents investigation of plasmonic properties of coupled metal nanowires arranged to form a finite linear chain. Coupled plasmon resonances of such structures embedded into dielectrics with different dielectric permittivity are studied. The main goals of the paper are to validate true potential of a plasmon nanowire-based structure in sensing applications and to reveal optimized configurations with narrowband plasmonic resonances and enhanced sensitivity.

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Advanced methods for measurement uncertainty evaluation

(MMA-2022, 2022) Zakharov, I.; Botsiura, O.

Disadvantages of the law of propagation of uncertainty underlying the implementation of the model approach in the GUM are analyzed. Advanced methods for implementing a model approach to measurement uncertainty evaluation are described, which allow eliminating the shortcomings of the GUM uncertainty framework: the law of propagation of distributions, the kurtosis method, the law of propagation of expanded uncertainty, the law of propagation of observational results for reliable evaluation of type A uncertainty for correlated and uncorrelated measurement results of input quantities.

Публікація

Aeolian Liquid Vibrations in Conical Tanks with Baffles under Wind Loading with Fuzzy Parameters

(2023) Sierikova, O.; Strelnikova, E.; Kriutchenko, D.; Degtyarev, K.; Gnitko, V.; Doroshenko, V.

The Aeolian liquid vibrations in conical reservoirs caused by low-velocity, steady winds have been under consideration. Both amplitudes and dominant frequencies of wind loadings have been constantly changed, so to adequately describe the vibration process, fuzzy logic methods have been applied. At the first stage, the crisp initial value problem for conical shells with and without baffles has been considered. The liquid inside the reservoirs has been supposed to be an incompressible and ideal one, and its flow induced by the forced harmonic excitation, has been considered as potential. So, there exists a potential to satisfy the Laplace equation. The impermeable condition has been used at wetted surface boundaries of the shell, whereas the dynamic and kinematic boundary conditions have been set on the free liquid surface. A system of singular integral equations has been obtained for values of the velocity potential and the function describing the free surface rise. Its solution has been gained by boundary element methods. The crisp boundary value problem has been reduced to the second-order system of differential equations. After receiving the crisp solution of this system, the initial data have been fuzzified, involving triangular fuzzy numbers, and the fuzzy initial value problem has been formulated. The numerical solution to this problem with uncertain intervals involved has been obtained and analyzed

Публікація

Airy Pulse Transformation by an Accelerated Medium Boundary

(CAOL, 2019) Zhyla, O. V.; Nerukh, A. G.; Gnatenko, A. S.

In the statement of a problem with a moving boundary there is one more idealization, namely, movement stationarity assuming that the movement has begun at infinite past time. Abandoning this idealization, by considering a movement that begins at a finite moment of time, leads to the appearance of new peculiarities in the wave transformation on a moving boundary. In this paper such peculiarities are considered with an abrupt uniform movement of a boundary beginning at zero moment of time, as well as with a smooth “turning on” of a boundary movement according to a relativistic uniformly accelerated law. In the latter approach the continuity of a boundary velocity change allows the development of the evolution of the wave transformation process to be traced.

Публікація

An initial and boundary value electromagnetic problem for plasma sphere

(ХНУРЕ, 2012) Remayeva, Т.

The exact expressions for the transformed field caused by a plasma sphere after its instant formation are obtained as a solution of an initial and boundary value electromagnetic problem for the Maxwell’s equations based on the longitudinal and the transverse spherical vector functions.

Публікація

Bonding and antibonding combinations of plasmons in aggregates of plasma columns

(IEEE, 2012) Stognii, N. P.; Sakhnenko, N. K.

Theoretical investigation of the plasmonic resonances of coupled cylindrical plasma columns is presented. Mechanism of plasmonic mode coupling in a pair of coupled plasma columns and in a cluster with square configuration that can be considered as bonding and antibonding combinations of isolated column plasmons is investigated

Публікація

‘Bright’ and ‘dark’ plasmons in the systems of metal nanowires

(IRE, 2014) Stognii, N. P.; Sakhnenko, N. K.

Many authors find SPs by investigating resonance peaks in Scattering Cross Section (SCS). This study cannot be considered as a complete one, because in this way only ‘bright’ plasmons can be seen, ’dark’ plasmons that do not couple efficiently to incident wave cannot be discovered in such a description. We developed nonquasistatical expressions for the eigenvalues of SPs that includes finding of eigenfrequencies and Q-factor. Using this approach all possible SPs can be found and investigated, including ‘dark’ and multipole ones.

Публікація

Changing of an Airy pulse form due to re-reflections inside a dielectric layer

(YSF, 2016) Kuryzheva, O. V.; Nerukh, A. G.

A problem of Airy pulse transformation by a plane-parallel layer is considered. A problem formulation is equivalent to a case of permittivity sharp change in a dielectric layer at zero moment of time. It allows to use the resolvent method for solution of the Volterra integral equation describing this phenomenon. It is shown a virtual structure of a pulse field inside the layer. Influence of a number of pulse re-reflections from the layer boundaries on a form of a primary pulse is analyzed.

Публікація

Coupled plasma cylindrical columns as sub-wavelength antenna

(КПИ, 2011) Stognii, N. P.; Sakhnenko, N. K.

We theoretically study the resonant properties of an aggregate of coupled cylinders filled with negative permittivity plasma. Such a problem has applications in optical and plasma antennas, intelligent antenna systems, and pulse-driven antenna arrays. Chain of columns of plasma can be used in the design of both transmitting and receiving antennas with a very broad frequency range and tunability that allows switching it on and off very fast. The Mie series expansion is used to derive the solution. Electromagnetic analysis of the spectrum of different plasmon resonances is presented.

Публікація

Coupled plasmon hybrid modes in aggregates of metal nanowires

(IEEE, 2015) Stognii, N. P.; Sakhnenko, N. K.

Investigation of the plasmonic resonances in aggregates of metal nanowires is presented. Mechanism of plasmonic mode coupling in a system of metal wires that can be considered as hybridization combinations of isolated wire plasmons is investigated.

Публікація

Development of a rangefinding method for determining the coordinates of targets by a network of radar stations in counter-battery warfare

(2022) Khudov, H.; Zvonko, A.; Lisohorskyi, B.; Solomonenko, Yu.; Mynko, P.; Glukhov, S.; Irkha, A.; Lishchenko, V.; Mishchenko, Y.; Khudov, V.

The increase in the accuracy of determining the coordinates of targets is explained by the use of a network of counter-battery radar stations and the rangefinding method for determining the coordinates of targets. The main advantage of using the rangefinding method for determining the coordinates of targets in a network of counter-battery radar stations is to ensure the required accuracy in determining the coordinates of targets without using accurate measurement of angular coordinates. The minimum geometry of the system, which ensures the use of the rangefinding method for determining coordinates, is given. The method of determining the coordinates of targets by a network of counter-battery radar stations has been improved. In contrast to the known ones, information about the range to the target is additionally used in a spatially distributed network of radar stations for counter-battery combat. The boundaries of the working zones of the network of two and three counter-battery radar stations are calculated. The features of creating a continuous strip using the rangefinding method for determining the coordinates of the target are considered. Statistical modeling of the rangefinding method for determining the plane coordinates of the target has been carried out. It has been established that the use of the rangefinding method ensures the determination of the planar coordinates of the target in a sector of at least 120°. The targets are at a distance of direct radio visibility in relation to the counter-battery radar. The root-mean-square error in determining the target range in this case is no more than 50 m. It has been established that the creation of continuous bands of a low-altitude radar field at a certain height is possible by arranging radar stations in a line. In this case, the distance between the counter-battery radar stations should be no more than half the target detection range at this height

Публікація

Development a method for determining the coordinates of air objects by radars with the additional use of multilateration technology

(Eastern-European Journal of Enterprise Technologies, 2021) Khudov, H.,; Mynko, P.; Ikhsanov, S.; Diakonov, O.; Kovalenko, O.; Solomonenko, Y.; Drob, Y.; Kharun, O.; Сherkashyn, S.; Serdiuk, O.

This paper reports an experimental study aimed at confirming disruptions in the operation of ADS-B receivers. The experimental investigation into disruptions in the operation of ADS-B receivers involved the FlightAware Piaware receiver. Examples of the disrupted performance of ADS-B receivers are given. It was found that the experimentally detected disruptions in the operation of ADS-B receivers could lead to a decrease in the accuracy of determining the coordinates of air objects with the joint use of the radar and multilateration technology. A method for determining the coordinates of an air object by radar with additional use of multilateration technology has been devised. The method involves the following stages: entering initial data, the calculation of distances between the points of reception and the air object, the computation of the inconsistency vector, the calculation of the matrix of partial derivatives taking into consideration the estimates of the coordinates of an air object at the previous iteration, the computation of the correction, the calculation of the refined coordinates of the air object. Unlike those known ones, the improved method for determining the coordinates of an air object by a radar additionally uses multilateration technology. The accuracy of determining the air objects' coordinates by a radar with the additional use of multilateration technology was estimated. It was stablished that the additional application of multilateration technology would reduce the error in determining the coordinates of an air object by 1.58 to 2.39 times on average, compared to using only an autonomous radar

Публікація

Diffraction of electromagnetic waves on an imperfectly conducting conical structure of a partial shape

(РАН, 2006) Doroshenko, V. A.; Kravchenko, V. F.; Pustovoit, V. I.

In this paper, we propose equivalent impedance-type boundary conditions on the surface of a thin conical surface taking into account its curvature; they are obtained from the exact solution for a thick conical grating.

Публікація

Diffraction of the plane electromagnetic wave on the structure incorporating two coaxial unclosed cones

(IEEE, 2007) Doroshenko, V. A.; Semenova, E. K.; Doroshenko, Ya. V.; Ruzhytskya, S. V.

The paper is developed to the investigation of plane wave diffraction on the 3D composite unclosed conical structure consisting of two cones with longitudinal slots. The rigorous analytical-numerical approach, based on the Kontorovich-Lebedev integral transform and the semi-inversion method, has been developed and applied to solve this problem.

Публікація

Dynamics of decelerating pulses at a dielectric layer

(Optical and Quantum Electronics, 2016) Nerukh, A.; Zolotariov, D.; Kuryzheva, O.; Benson, T.

Time dependent electromagnetic pulses propagating with deceleration along the dominant propagation direction, and passing through a dielectric layer are investigated in the 1D + T case. This is achieved using an integral equation in the paraxial approximation obtained via the Green’s function symmetric with respect to the propagation direction

Публікація

Eigenvalue problem in a linear chain of coupled infinite-long plasma cylinders

(IRE, 2011) Stognii, N. P.; Sakhnenko, N. K.

Strong interest in the electromagnetic wave propagation and scattering in the presence of plasma objects is due to the wide range of potential applications of such study. Tuning of resonant characteristics of resonators by free carrier plasma injections can be used in active switches or tunable filters. Transient phenomena in plasma lead to the possibility of the frequency upshifting and the generation of waves. Using resonators composed of negative permittivity materials such as plasma can form the basis of effective small-size antenna elements. The main goal of this paper is to analyze the plasmonic resonances in finite array of plasma coupled cylinders.

Публікація

Electromagnetic excitation of PEC slotted cones by elementary radial dipoles – a semi-inversion analysis

(IEEE, 2008) Semenova, E. K.; Doroshenko, V. A.

This paper presents a novel method that is based on the use of the Kontorovich-Lebedev integral transform and the semi-inversion technique, developed for building the efficient and accurate numerical solutions to the boundary-value problems of electromagnetic wave scattering by 3D coaxial slotted cones.

Публікація

Electromagnetic wave diffraction by a cone with longitudinal slots and a solid conic screen inside

(IEEE, 2003) Doroshenko, V. A.; Semenova, E. K.

A numerical-analytical solution of the problem of excitation of an unlimited perfectly conducting biconical surface is considered. Surface consists of both a cone with periodical longitudinal slots and an internal solid conical screen. The effects of slots and solid cone on the Fourier coefficient of the electromagnetic field components and the scattering patterns are discussed. The obtained results are in good agreement with previously recognized ones for solid bicone structure.

Публікація

Electromagnetic waves diffraction a system of open cones in time domain

(IEEE, 2010) Doroshenko, V. A.; Artjukh, A. V.; Parhomenko, V. A.

A model problem of electromagnetic waves diffraction on an equalperiodical multilayered perfectly conducting conical grating is considered. The solution method is based on using the Meler-Fock integral transforms and the method of the coupling problem. This allows both analytical and numerical solutions obtaining.

Публікація

Evolution of an Airy pulse energy flow induced by a dielectric plane boundary

(CAOL, 2016) Kuryzheva, O. V.; Nerukh, A. G.

Transformation of energy flows of an electromagnetic Airy pulse by a plane boundary of a dielectric is considered. It is shown that a problem formulation is equivalent to a case of a permittivity sharp change in a half space at zero moment of time. It allows to use the resolvent method for solution of the Volterra integral equation describing the phenomenon. Explicit expressions for transmitted and reflected pulses are obtained and energy flows are analyzed.

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