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Envelope equation for water waves : Soliton turbulence and wavebreaking
Journal of Ocean Engineering and Marine Energy. 2017. Vol. 3. No. 4. P. 409–415.
Dyachenko A., Kachulin D., Zakharov V.
Water waves have long been a subject of attention of both mathematicians and physicists. The formulation of the problem is simple enough to be considered fundamental, but as of yet many questions still remain unanswered and many phenomena associated with wind-driven turbulence remain puzzling. We consider a “unidirectional” motion of weakly nonlinear gravity waves, i.e., we assume that the spectrum of the free surface contains only nonnegative wavenumbers. We use remarkably simple form of the water wave equation that we named “the super compact equation”. This new equation includes a nonlinear wave term (à la NLSE) together with an advection term that can describe the initial stage of wave breaking. This equation has also very important property. It allows to introduce exact envelope for waves without assumption of narrowness bandwidth.
Брычков М. Е., Незнанов А.А., Программирование 2026 № 4 С. 50–66
The matrix profile (MP) quickly became one of the most important time series preprocessing methods when it was introduced in 2016, facilitating the solution of a wide range of time series analysis problems, in particular anomaly and pattern detection problems. The high significance has led to the emergence of various tools for MP calculating, but ...
Added: October 9, 2026
ООО "Издательство Юрайт ", 2026.
The Collection of Olympiad Problems (COP) in Probability Theory and Mathematical Statistics (PTMS) is offered as a teaching aid primarily for university students and faculty as a developmental supplementary resource, expanding the range of problems to be solved in lectures, seminars, and out-of-class independent work with students in various formats, including (as the title suggests) ...
Added: October 9, 2026
Aleskerov F. T., Вайншток А. П., Делахова А. М. et al., Информационные процессы 2026 Т. 26 № 3 С. 895–913
The development and effective management of territorial entities are priority issues for all states, particularly in the context of the digital transformation of public administration. Over the past decade, the integration of information technologies into municipal and regional planning has significantly altered approaches to strategic development, service delivery, and public engagement. This paper describes the ...
Added: October 9, 2026
Kupavskii A., Noskov F., Forum of Mathematics, Sigma 2026 Vol. 14 Article 124
We call a family of $s$ sets $\{F_1, \ldots, F_s\}$ a sunflower with $s$ petals if, for any distinct $i, j \in [s]$, one has $F_i \cap F_j = \cap_{u = 1}^s F_u$. The set $C = \cap_{u = 1}^s F_u$ is called the {\it core} of the sunflower. It is a classical result of ...
Added: October 8, 2026
Ozhegov R., Махлуф М., Goltsman G. et al., Инженерная физика 2026 № 8 С. 27–39
This paper investigates the theoretical limits of object detection within isotropic scattering media using single-photon lidar. Within a simplified model, we derive the fundamental relationship between the maximum attainable detection range and the required photon count per pulse. Two distinct limiting regimes are analyzed: the ballistic photon regime, which maintains high spatial resolution but necessitates ...
Added: October 8, 2026
Didenkulova E., Chugunov V., Didenkulova I., Wave Motion 2026 Vol. 147 Article 103787
This work presents a new analytical solution of the shallow water theory for cylindrical propagation of long tsunami-like waves in the basin of variable depth. Considered model cases are related to tsunami wave propagation from an asteroid fallen into the sea, or from underwater volcanic eruptions. The corresponding bottom geometries represent radially symmetric obstacles such ...
Added: October 8, 2026
Flamarion M., Didenkulova E., Pelinovsky E., Physics Letters A 2026 Vol. 598 Article 132218
In this letter, bipolar solitary wave interactions in the Schamel equation are revisited numerically. Two simulation settings are considered: repeated collisions in a periodic domain, and the interaction of a positive solitary wave with a train of negative polarity solitary waves of equal amplitude. In the first case, when the amplitudes are comparable, the larger ...
Added: October 8, 2026
Flamarion M. V., Pelinovsky E., Chaos, Solitons and Fractals 2026 Vol. 213 No. 2 Article 119245
This article concerns the study of modulational instability in the rotated-modified Gardner–Whitham (rmGW) equation. This model incorporates both quadratic and cubic nonlinearities, similarly to the Gardner equation, while also retaining the fully dispersive character of the Whitham equation together with a large-scale dispersive term analogous to that in the Ostrovsky equation. Using a classical multiple-scale asymptotic expansion, we ...
Added: October 8, 2026
Люксембург А. А., УРСС, 2005.
Изучается возможность автоматизированного построения математических теорий. Рассматривается дедуктивная система, основанная на языке логики предикатов первого порядка, объектами системы являются математические выражения или формулы, которые описывают математические объекты или их свойства. В дедуктивной системе выводятся математические определения и теоремы. Для доказательства теорем используются методы автоматического доказательства. Разработан алгоритм, выводящий часть формул системы. Для решения задачи используется аппарат математической ...
Added: October 7, 2026
Aleskerov F. T., Chaika E., Дерендяев А. Б. et al., Procedia Computer Science 2026 No. 287 P. 590–595
Under conditions of dynamic socio-economic changes, effective planning and decision-making are key factors in ensuring a high quality of life for the population in territories. This paper presents a decision support system for territorial administrations for the development and implementation of sustainable development strategies, using one of the regions of the Russian Federation – the ...
Added: October 7, 2026
Bernardin C., Gonçalves P., Olla S., Mathematical Physics Analysis and Geometry 2024 Vol. 27 No. 7
We consider the macroscopic limit for the space-time density fluctuations in the open symmetric simple exclusion in the quasi-static scaling limit. We prove that the distribution of these fluctuations converge to a gaussian space-time field that is delta correlated in time but with long-range correlations in space. ...
Added: October 6, 2026
Bernardin C., Chhaibi R., Najnudel J. et al., Probability Theory and Related Fields 2026 Vol. 195 P. 1823–1875
We study the celebrated Shiryaev-Wonham filter (Wonham, W.M., in J. Soc. Ind. Appl. Math. 347–369, 1964) in its historical setup, where the hidden Markov jump process has two states. We are interested in the weak noise regime for the observation equation. Interestingly, this becomes a strong noise regime for the filtering equations. Earlier results of ...
Added: October 5, 2026
Ismailov A., Spiridonov V., Успехи математических наук 2026 Т. 81 № 5 С. 183–184
Получена новая формула для цепной дроби Аски–Вильсона в форме отношения двух q-гипер-геометрических рядов. ...
Added: October 5, 2026
Isaev T. F., Шаров А. Н., Журнал вычислительной математики и математической физики 2026 Т. 66 № 1 С. 83–93
Исследуются свойства оптических покрытий на основе использования упрощенного симулятора ошибок в толщинах слоев покрытий при их напылении. Обосновывается возможность такого подхода. Выводятся аналитические оценки среднеквадратичного значения нормы вектора ошибок и степени коррелированности ошибок в толщинах слоев покрытия. Изучается зависимость среднеквадратичного значения нормы вектора ошибок и свойств покрытия от уровня случайных ошибок в слоях. ...
Added: October 5, 2026
Осипова А. М., Пилипенко С. В., Novikov D. I. et al., Physical Review D - Particles, Fields, Gravitation and Cosmology 2026 Vol. 114 Article 063522
We investigate the prospects for observing a specific spectral distortion of the cosmic microwave
background, which occurs due to the anisotropy of the radiation when it is scattered by hot plasma of
galaxy clusters. Detection of this anisotropic Sunyaev-Zel’dovich effect would enable an independent
measurement of the CMB anisotropy multipoles with l 1⁄4 1, 2, 3, allow the ...
Added: October 5, 2026
Meshcheryakov A. A., A.R. Safin, Kalyabin D. et al., Physics of the Solid State 2025 Vol. 67 No. 1 P. 72–77
The phenomenon of mode hybridization in the exchange-coupled two-layer antiferromagnet|ferromagnet structure has been theoretically investigated. Expressions describing the dependence of the resonant frequencies of magnetization oscillations on the external magnetic field have been obtained by the method of Hamiltonian formalism. The effect of the coupling strength between the ferro- and antiferromagnetic layers on the width ...
Added: July 2, 2025
Pelinovsky E., Talipova T., Didenkulova E., Physics Letters A 2024 Vol. 507 Article 129489
The dynamics of waves of sign-variable shape has been studied within the framework of the Hopf equation (ut +Fux = 0) with a non-analytic propagation velocity containing the modulus of the function at the zero crossing (F ~ |u|α). It is shown that Riemann waves exist only for a certain smoothness of the function F[u(x)] ...
Added: May 30, 2024
Dyachenko A., Kachulin D., Zakharov V., Lobachevskii Journal of Mathematics 2017 Vol. 38 No. 5 P. 888–892
Presented are the results of experiments on calculation of Probability Distribution Functions for elevations of waters waves in numerical tank. Statistics of waves of anomalous amplitude, or freak-waves were compared both for nonlinear and linear models. Obviously, linear model demonstrates the exact Rayleigh distribution of surface elevations while PDFs for nonlinear equation have tails (for ...
Added: October 22, 2022
Dyachenko A., Kachulin D., Zakharov V., Journal of Fluid Mechanics 2017 Vol. 828 P. 661–679
Mathematicians and physicists have long been interested in the subject of water waves. The problems formulated in this subject can be considered fundamental, but many questions remain unanswered. For instance, a satisfactory analytic theory of such a common and important phenomenon as wave breaking has yet to be developed. Our knowledge of the formation of rogue ...
Added: October 22, 2022
Dremov S., Kachulin D., Dyachenko A., Fluids 2022 Vol. 7 No. 6 Article 204
In this paper we propose two Hamiltonian models to describe two-dimensional deep water waves propagating on the surface of an ideal incompressible three-dimensional fluid. The idea is based on taking advantage of the Zakharov equation for one-dimensional waves which can be written in the form of so-called compact equations. We generalize these equations to the ...
Added: October 22, 2022
Kachulin D., Dyachenko A., Zakharov V., Fluids 2020 Vol. 5 No. 2 Article 67
We investigate and compare soliton turbulence appearing as a result of modulational
instability of the homogeneous wave train in three nonlinear models for surface gravity waves:
the nonlinear Schrödinger equation, the super compact Zakharov equation, and the fully nonlinear
equations written in conformal variables. We show that even at a low level of energy and average
wave steepness, the ...
Added: October 22, 2022
Dyachenko A., Fluids 2019 Vol. 4 No. 1 Article 47
The waves on a free surface of 2D deep water can be split into two groups: the waves moving to the right, and the waves moving to the left. A specific feature of the four-wave interactions of water waves allows to describe the evolution of the two groups as a system of two equations. The ...
Added: October 20, 2022
Slunyaev A., Степанянц Ю. А., Physics of Fluids 2022 Vol. 34 No. 7 Article 077121
We study the nonlinear modulation property of flexural-gravity waves on a water surface covered by a compressed ice sheet of given thickness and density in a basin of a constant depth. For weakly nonlinear perturbations, we derive the nonlinear Schrodinger equation and investigate the conditions when a quasi-sinusoidal wave becomes unstable with respect to amplitude modulation. The ...
Added: October 13, 2022
Morozova T. I., Kopnin S. I., Popel S. I. et al., Physics of Plasmas 2021 Vol. 28 No. 3 Article 033703
The development of modulational instability involving dust acoustic perturbations in dusty ionospheric plasma and in dusty plasmas of meteor tails in Earth’s ionosphere was considered. The effect of collisions of electrons, ions, and dust grains with neutrals at different altitudes was estimated. It is shown that, in this case, the influence of collisions of electrons and ions ...
Added: March 11, 2021