“Missouri Through Soviet Eyes”

In 1935, Russian satirists Ilya Ilf and Yevgeny Petrov bought a Ford and drove across the United States and back; their observations shaped the ideas of Russians about the United States for some three decades. One of the places they visited was Hannibal, Missouri. Here is their account, including their own photos

Object pop-up: Can we infer 3D objects and their poses from human interactions alone?

The intimate entanglement between objects affordances and human poses is of large interest, among others, for behavioural sciences, cognitive psychology, and Computer Vision communities. In recent years, the latter has developed several object-centric approaches: starting from items, learning pipelines synthesizing human poses and dynamics in a realistic way, satisfying both geometrical and functional expectations. However, the inverse perspective is significantly less explored: Can we infer 3D objects and their poses from human interactions alone? Our investigation follows this direction, showing that a generic 3D human point cloud is enough to pop up an unobserved object, even when the user is just imitating a functionality (e.g., looking through a binocular) without involving a tangible counterpart. We validate our method qualitatively and quantitatively, with synthetic data and sequences acquired for the task, showing applicability for XR/VR. The code is available at https://github.com/ptrvilya/object-popup.Comment: Accepted at CVPR'2

Strongly subradiant states in planar atomic arrays

The optically trapped ensembles of atoms provide a versatile platform for storing and coherent manipulation of quantum information. However, efficient realization of quantum information processing requires long-lived quantum states protected from the decoherence e.g. via spontaneous emission. Here, we theoretically study collective dipolar oscillations in finite planar arrays of quantum emitters in free space and analyze mechanisms that govern the emergence of strongly subradiant collective states. We demonstrate that the external coupling between the collective states associated with the symmetry of the array and with the quasi-flat dispersion of the corresponding infinite lattice plays a crucial role in the boost of their radiative lifetime. We show that among different regular arrangements of the atoms the square atomic arrays support eigenstates with minimal radiative losses that scale with the total number of atoms $N_{tot}$ as $\propto N_{tot}^{-5}$

Numerical simulation of stages number influence to the characteristics of a looped tube thermoacoustic Stirling engine

Background and Objectives: The traveling wave thermoacoustic engine is a variation of the Stirling engine family. With an increase in the number of stages of a traveling wave thermoacoustic engine from one to four, an improvement in the characteristics of the acoustic wave in the regenerator zone is observed, the temperature difference between the heat exchangers required to start the engine decreases, and the efficiency increases. For this reason, it is important to study the patterns of changes in engine characteristics with a further increase in the number of stages. The aim of the work was to study the influence of the number of stages on the characteristics of the acoustic wave in the engine. Materials and Methods: A numerical calculation of eight models of engines with the number of stages from three to ten was carried out in the Delta EC program. The working gas is argon under a pressure of 1.5 MPa, the diameter of the heat exchangers is 160 mm, the diameter of the acoustic resonator is 41.2 mm, the length of the looped engine resonator for all models was 8 meters. The stages in all engines were structurally the same. In the course of the calculations, the number of stages and the number of acoustic loads changed, while maintaining the same total length of the hull-resonator. For each of the eight models studied, the acoustic load was optimized to achieve the maximum engine efficiency. Conclusion: It was shown that with an increase in the number of stages from three to ten, there is a gradual increase in the phase difference between the pressure and velocity oscillations, that is, the wave approaches the parameters of a standing wave in the entire cavity of the resonator. In this case, the maximum acoustic load power and efficiency were observed when the number of stages was equal to five. With an increase in the number of stages from five to ten, the power of each individual stage decreased by 15.8%, and the efficiency decreased by 8%

Interaction of vector solitons with a nonlinear interface

We develop the analytical method of field momenta for analyzing the dynamics of optical vector solitons in photorefractive nonlinear media. First, we derive the effective evolution equations for the parameters of multi-component solitons composed of incoherently coupled beams and investigate the soliton internal oscillations associated with the relative motion of the soliton components. Then, we apply this method for analyzing the vector soliton scattering by a nonlinear interface. In particular, we show that a vector soliton can be reflected, transmitted, captured, or split into separate components, depending on the initial energy of its internal degree of freedom. The results are verified by direct numerical simulations of spatial optical solitons in photorefractive nonlinear media

Moment conditions in strong laws of large numbers for multiple sums and random measures

The validity of the strong law of large numbers for multiple sums $S_n$ of independent identically distributed random variables $Z_k$, $k\leq n$, with $r$-dimensional indices is equivalent to the integrability of $|Z|(\log^+|Z|)^{r-1}$, where $Z$ is the typical summand. We consider the strong law of large numbers for more general normalisations, without assuming that the summands $Z_k$ are identically distributed, and prove a multiple sum generalisation of the Brunk--Prohorov strong law of large numbers. In the case of identical finite moments of irder $2q$ with integer $q\geq1$, we show that the strong law of large numbers holds with the normalisation $\|n_1\cdots n_r\|^{1/2}(\log n_1\cdots\log n_r)^{1/(2q)+\varepsilon}$ for any $\varepsilon>0$. The obtained results are also formulated in the setting of ergodic theorems for random measures, in particular those generated by marked point processes.Comment: 15 page

Larch Forests of Middle Siberia: Long-Term Trends in Fire Return Intervals

Fire history within the northern larch forests of Central Siberia was studied (65 + deg N). Fires within this area are predominantly caused by lightning strikes rather than human activity. Mean fire return intervals (FRIs) were found to be 112 49 years (based on fire scars) and 106 36 years (based on fire scars and tree natality dates). FRI were increased with latitude increase and observed to be about 80 years at 64 deg N, about 200 years near the Arctic Circle and about 300 years nearby the northern range limit of larch stands (approximately 71 deg + N). Northward FRI increase correlated with incoming solar radiation (r = 0.95). Post Little Ice Age (LIA) warming (after 1850) caused approximately a doubling of fire events (in comparison with a similar period during LIA). The data obtained support a hypothesis of climate-induced fire frequency increase

Analysis of the state of information security on the basis of surious emission electronic components

The article deals with an approach to determining the state of information security based on the analysis of spurious emission of electromagnetic components. Attention is drawn to the possibility of the formation of the data, obtain samples for the analysis of the state of the information security. An experiment in result of which the amplitude-frequency characteristics of the analyzed radiation. Formed data tuples estimated probability values correctly determine the state on the basis of the data obtained