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Range Distance Requirements for Large Antenna Measurements for Square Aperture With Uniform Field Distribution
IEEE Antennas and Wireless Propagation Letters. 2018. Vol. 17. No. 7. P. 1257–1260.
Skulkin S. P., Turchin V., Kascheev N. I.
Frequency dependences of the field for constant angle
of observation measured by different probes at different distances
are discussed.We consider the case of the square aperture antenna
with the uniform field distribution. The analysis is based on timedomain
physical optics method of field calculation. We show and
explain the effect of sidelobe reduction when a big square probe is
placed at a finite distance from square aperture antenna. Errors
of the sidelobe levels of the antenna radiation pattern (ARP) in the
cases of different sizes of the probe placed at different distances
are shown. We show an optimal probe size and an optimal measurement
distance between antennas. We also show and explain
the effect of a large distortion of the ARP first zero, measured by
the big probe at the finite distance.
Guterman A., Jonoska N., Kreines E. et al., Proceedings of the Edinburgh Mathematical Society 2026 Vol. 69 No. 3 P. 1041–1057
We provide four equivalent combinatorial conditions for a simple assembly graph (rigid vertex graph where all vertices are of degree 1 or 4) to have the largest number of Hamiltonian sets of polygonal paths relative to its size. These conditions serve to prove the conjecture that such a maximum, which is equal to 𝐹_(2𝑛+1) −1, ...
Added: September 27, 2026
Vergeles S. S., Vointsev I., Physics of Fluids 2026 Vol. 38 P. 024117-1–024117-8
We analytically consider the problem of the Langmuir instability. The instability describes emergence of transverse modulation of horizontal current with vertical shear, when it is superimposed on surface wave co-directional with the flow. Compared to the Craik–Leibovich scheme, we account for the scattering of surface wave on the modulated current, which is significant if the ...
Added: September 26, 2026
Frolov N. Y., Klokov A. Y., Sharkov A. I. et al., Applied Physics Letters 2026 Vol. 128 P. 092201-1–092201-5
Understanding the properties of two-dimensional material interfaces with the substrate is necessary for device applications. Surface acoustic wave propagation through a layered material flake on a substrate could provide unique information on the transverse rigidity of the flake-to-substrate interaction. Ultrasonic waves were generated by a focused femtosecond laser pulse at the surface of a model ...
Added: September 26, 2026
Shishkina E., Современная математика. Фундаментальные направления 2026 Т. 72 № 1 С. 52–67
In this paper, we construct a weighted Sobolev space of fractional order based on the
generalized Bessel potential.We apply these results to the analysis of the singular fractional Schr¨odinger
equation. To solve the Cauchy problem for this equation, we prove an estimate that relates the norm of
the solution to the norm of the initial condition in the ...
Added: September 26, 2026
Shishkina E., Computational Mathematics and Mathematical Physics 2026 Vol. 66 No. 5 P. 804–815
This article demonstrates that the Laplace–Bessel operator generates a strongly continuous
semigroup on a weighted Lebesgue space. Using this semigroup, we define the fractional Laplace–
Bessel operator via Balakrishnan’s formula. Furthermore, we derive three distinct representations for
fractional powers of the negative Laplace–Bessel operator. ...
Added: September 26, 2026
Kolokoltsov V., Shishkina E., Journal of Theoretical Probability 2026 P. 39–83
In this paper, we introduce a new construction of fractional derivatives and integrals
with respect to a function, based on a matrix approach. We believe that this is a powerful
tool in both analytical and numerical calculations.We begin with the differential
operator with respect to a function that generates a semigroup. By discretizing this
operator, we obtain a matrix ...
Added: September 26, 2026
Petr Kucheriaviy, Bulletin of the Australian Mathematical Society 2026
We prove that an analogue of Rogers’ theorem on sieving holds for an order if and only if the order is a Dedekind domain. We also prove that it holds for a finite commutative ring if and only if the ring is a direct product of local rings with linearly ordered ideals. ...
Added: September 25, 2026
Войтович В. И., Makhov I., Мельниченко И. А. et al., Optics Letters 2026 Vol. 51 No. 17 P. 4872–4875
The influence of cavity surface passivation with SiO2 coating deposited by the plasma-enhanced chemical vapor deposition technique is investigated for injection microdisk lasers with an InGaAsN/GaAs quantum well active region. The electroluminescence spectra of the microdisk lasers with cavity diameters ranging from 12 to 32 μm with and without sidewall surface passivation were studied for a ...
Added: September 25, 2026
Бабичев А. В., Makhov I., Kryzhanovskaya N. et al., Оптика и спектроскопия 2026 Т. 134 № 3 С. 272–277
Представлены результаты по реализации генерации при повышенных температурах в лазерах с длиной волны генерации 980 nm на основе вертикального микрорезонатора с использованием непоглощающих на длине волны оптической накачки зеркал. Минимальная пороговая мощность накачки составила ~0.8 mW и соответствовала температуре 150 K. Добротность микрорезонатора, определенная на пороге генерации, превысила 13000. Максимальная рабочая температура микролазера составила 195 ...
Added: September 25, 2026
Бабичев А. В., Makhov I., Kryzhanovskaya N. et al., Письма в Журнал технической физики 2026 Т. 52 № 12 С. 40–43
Реализована одночастотная генерация при 300 K в лазерах на основе вертикального микрорезонатора. Для лазеров с полупроводниковым выводным зеркалом пороговая плотность мощности накачки составила 6.5 kW/cm2. Добротность микрорезонатора и длина волны излучения, определенные на пороге генерации, равнялись 8800 и ~ 959.8 nm. Применение конструкции микрорезонатора с гибридным выводным зеркалом позволило повысить добротность микрорезонатора (до 12 360) ...
Added: September 25, 2026
Бабичев А. В., Makhov I., Kryzhanovskaya N. et al., Письма в Журнал технической физики 2026 Т. 52 № 18 С. 30–34
Представлены результаты реализации генерации при комнатной температуре в планарных вертикальных микрорезонаторах на основе зеркал Al0.2Ga0.8As/Al0.9Ga0.1As. При 300 K пороговая плотность мощности и добротность на пороге генерации составили 11.4± 0.7 kW/cm2 и 5070± 160 соответственно. Двукратное превышение порога генерации привело к увеличению добротности микрорезонатора до 19 000. Эффективный латеральный теплоотвод подтвержден малым сдвигом энергии кванта, который составил ...
Added: September 25, 2026
Пелевин Ф. Е., Математические заметки 2026 Т. 120 № 1 С. 159–163
Две не равные тождественно нулю функции (последовательности элементов некоторого поля) будем называть эквивалентными, если они удовлетворяют функциональному уравнению типа теорем сложения тэта-функций. Основной результат работы состоит в том, что рассматриваемое отношение действительно является отношением эквивалентности. ...
Added: September 25, 2026
Shimanogov I. N., Vyalyi M., Siberian Mathematical Journal 2026 Vol. 67 No. 5 P. 1203–1212
We consider a class of Boolean algebras formed by intersections of regular languages with
a given language. In the case where such an algebra is isomorphic to the algebra of regular languages,
we prove the existence of an isomorphism that is computable using oracles for the regular realizability
problem and the infinite regular realizability problem. This result yields ...
Added: September 25, 2026
Ramazanov I., Bukh A., Shepelev Igor A., Chaos 2026 No. 36 P. 083150–083150
We investigate how stochastic Poisson impulsive forcing influences the spatiotemporal dynamics of a two-dimensional network of Hindmarsh–Rose neurons. Unlike continuous noise, impulsive forcing introduces discrete, state-dependent perturbations, making the system response highly sensitive to both the statistics and the spatial structure of the input. In most of the parameter space, stochastic impulses destabilize the initial ...
Added: September 24, 2026
Levashev V., / Series arXiv "math". 2026. No. 2609.06010.
We prove that continuous A-bilinear pairings on the ring of Laurent series that are invariant under continuous automorphisms coincide, up to a constant, with the pairing given by the residue of a differential form over any commutative associative ring with identity. ...
Added: September 24, 2026
Budkov Y., Kiselev M. G., Journal of Chemical Physics 2026 Vol. 165 No. 12 Article 124508
We develop a three-mode statistical-mechanical theory for a two-conformer
solute in a near-critical solvent. A compressible lattice model with
vacancies yields the Gaussian free-energy functional for a critical conserved
density, an orthogonal noncritical conserved mode, and the local conformer
fraction. Their couplings follow from packing and cohesive interactions,
rather than being introduced phenomenologically. Kawasaki transport of the
two conserved fields and ...
Added: September 24, 2026
Sokolov V., Adler V. E., Journal of Geometry and Physics 2026 Vol. 227 Article 105860
The group reduction procedure is applied to vector generalizations of the NLS, mKdV,
and KdV equations. The resulting ODE systems admit isomonodromic Lax representations
and are multicomponent generalizations of the Painlevé equations P 1, P 2, P 34, and P 4.
Some of them can be interpreted as nonautonomous deformations of well-known systems
integrable in the Liouville sense, in ...
Added: September 24, 2026
Sokolov V., BALAKHNEV M. Y., Ufa Mathematical Journal 2026 Vol. 18 No. №3 P. 85–93
A collection of miscellaneous continuous, semi-discrete, and discrete integrable
systems can be associated with each integrable evolution equation of the KdV type. We provide them for the Schwarz — KdV equation and generalize to the vector case. The existence
of these vector generalizations is a non-trivial found fact, no mathematical explanation of
which is known yet. ...
Added: September 24, 2026
Sergey P. Skulkin, Uskov G. K., Lysenko N. A. et al., IEEE Access 2023 Vol. 11 P. 66028–66034
In this study, we describe the specific features of the near-field distribution of a uniformly
illuminated aperture. An analytical method based on physical optics in the time domain is used to calculate
the field intensity. The primitive impulse response function makes it possible to calculate the near-field
distribution of the antenna. The difference in the amplitudes of the ...
Added: September 22, 2023
Lysenko N. A., Uskov G. K., Bobreshov A. et al., , in: 2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, IEEECONF 2020 - Proceedings.: IEEE, 2020. P. 1057–1058.
Added: November 10, 2020
Skulkin S. P., Lysenko N. A., Uskov G. K. et al., IEEE Antennas and Wireless Propagation Letters 2019 Vol. 18 P. 1036–1040
The letter describes a transient far-field calculation
method.We consider a case of circular plane aperture with various
field distributions.The method allows to obtain the analytical forms
presented in trigonometric functions. New formulas are given. The
behavior of the far field in the time domain is considered. ...
Added: October 9, 2020
Skulkin S. P., Lysenko N. A., Uskov G. K. et al., IEEE Antennas and Wireless Propagation Letters 2020 Vol. 19 P. 1516–1520
In this letter, we present a novel time-domain analytic
formula for the elementary radiator antenna pattern of a metal
plane surface with infinite conductivity. The formula is presented
as a function of time and the integration angle. The formula refers
to a flat metal aperturewithout regard to its shape.We also describe
a novel equation for the primitive impulse response function ...
Added: October 8, 2020
Chen L., Davydov Y., Gribkova N. et al., Mathematical Methods of Statistics 2018 Vol. 27 P. 83–102
We introduce and explore an empirical index of increase that works in both deterministic and random environments, thus allowing to assess monotonicity of functions that are prone to random measurement errors. We prove consistency of the index and show how its rate of convergence is influenced by deterministic and random parts of the data. In ...
Added: February 28, 2020
Skulkin S. P., Турчин В. И., Kascheev N. I. et al., В кн.: Сборник трудов XXIV Международной научно-технической конференции Радиолокация, навигация, связь. Том 4. – Воронеж: ООО «Вэлборн», 2018.Т. 4.: Воронеж: Общество с ограниченной ответственностью "Вэлборн", 2018. С. 83–88.
Errors of radiation patterns (RP) on measurement of distance and on sizes of test and probe antennas are discussed. We consider the case of circular aperture antenna with uniform field distribution. The analysis is based on time-domain (TD) physical optics (PO) method of field calculation [1-2]. We show that the optimal measurement distance with respect to acceptable small errors ...
Added: October 26, 2018