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The main technology currently used in wood harvesting in Russia is the cut-to-length technology (CTL) based on the use of two machine types: harvesters and forwarders. Powerful and manoeuvrable hydraulic manipulators (cranes) are a main part of the equipment of both the harvester and the forwarder. A statistical analysis of ergonomic parameters of the manipulator control system equipped with partial automation option is described in this article. Two machines were studied in natural field conditions. Differences in the frequency and duration of telescopic extension boom control activations were identified. The distributions of the extension boom use parameters for the crane of the logging machines were defined. It can be used to build various models for the analysis of promising crane design solutions. It is determined that the duration of the rocker switch single press has a log-normal distribution and the period between switch activations has an exponential distribution.

Brain‐inspired computing, reconfigurable optical metamaterials, photonic tensor cores, and many other advanced applications require next‐generation phase‐change materials (PCMs) with better energy efficiency and a wider thermal and spectral range for reliable operations. Germanium ditelluride (GeTe2), with higher thermal stability and a larger bandgap compared to current benchmark PCMs, appears promising for THz metasurfaces and the controlled crystallization of atomically thin 2D materials. Using high‐energy X‐Ray diffraction supported by first‐principles simulation, the atomic structure in semiconducting pulsed laser deposition films and metallic high‐temperature liquids is investigated. The results suggest that the structural and chemical metastability of GeTe2, leading to disproportionation into GeTe and Te, is related to high internal pressure during a semiconductor–metal transition, presumably occurring in the supercooled melt. Similar phenomena are expected for canonical GeS2 and GeSe2 under high temperatures and pressures. [ABSTRACT FROM AUTHOR]

Harvesters and forwarders are the main part of cut-to-length logging system equipment. The perfection of the hydraulic cranes has a very large impact on the overall operating efficiency of these forest machines. The impact of the crane partial automation on the operator’s work cycle and workload is described in this article. Two machines were studied in field conditions. Differences in the frequency and duration of telescopic extension boom control activations were identified. It was determined that, as a result of automation, one of the degrees of freedom of the crane controls is almost completely excluded from use in the case of the forwarder. A significant reduction in the duration of its use is observed in the case of the harvester. As a result, this saves the psycho-physiological resources of the operator for more efficient use of the remaining degrees of freedom, which, coupled with a simpler and more intuitive logic of the controls operation, improves the productivity, accuracy and safety of cut-to-length logging. In addition, a simpler work algorithm reduces the level of stereotyping of the operator’s actions, fatigue and loss of attention, which usually emerge at the end of the shift. This work was supported by the Russian Federation Ministry of Science and Higher Education (state research target, theme no. 075-03-2023-128).

The low energy interactions between axions and electromagnetic fields that arise in models with heavy dyons charged under a spontaneously broken global axial U(1) symmetry are derived using the path integral approach. Hence, generic axion‐Maxwell equations relevant for experimental searches are obtained. It is found that the structure of the axion Maxwell equations can be significantly different compared to what is normally assumed in the literature, as the derived equations feature new axion‐dependent terms including CP‐violating ones. The new terms can reconcile the Peccei–Quinn solution to the strong CP problem with astrophysical axion hints, as well as give unique signatures in light‐shining‐through‐wall and haloscope experiments. Moreover, via the latter signatures, these experiments can indirectly probe the existence of heavy dyons. [ABSTRACT FROM AUTHOR]

Recently, interactions between putative axions and magnetic monopoles have been revisited by two of the authors.[1] It is shown that significant modifications to conventional axion electrodynamics arise due to these interactions, so that the axion–photon coupling parameter space is expanded from one parameter gaγγ$g_{a\gamma \gamma }$ to three (gaγγ,gaAB,gaBB)$(g_{a\gamma \gamma },g_{aAB},g_{aBB})$. Poynting theorem is implemented to determine how to exhibit sensitivity to gaAB$g_{aAB}$ and gaBB$g_{aBB}$ using resonant haloscopes, allowing new techniques to search for axions and a possible indirect way to determine if magnetically charged matter exists. [ABSTRACT FROM AUTHOR]

An approach to the optimal timber transport scheduling is described in the paper. A description of this problem is given, a multi-criteria mathematical model is created. It is noted that the problem belongs to the class of General vehicle routing problems (GVRP) associated with the job-shop scheduling. A hybrid algorithm for solving this problem based on the decomposition method using the simplex method and the genetic algorithm is developed. Testing of the proposed approach using real data from wood harvesting enterprises showed its effectiveness. The algorithm was implemented in “Opti-Wood” decision support system for wood harvesting planning and management, developed by Opti-Soft company (Russia).

We present algorithms and results of automated processing of LiDAR measurements obtained during VEGILOT measuring campaign in Paris in autumn 2014 in order to study horizontal turbulent atmospheric regimes on urban scales. To process images obtained by horizontal atmospheric scanning using Doppler LiDAR, the method is proposed based on texture analysis and classification using supervised machine learning algorithms. The results of the parallel classification by various classifiers were combined using the majority voting strategy. The obtained estimates of accuracy demonstrate the efficiency of the proposed method for solving the problem of remote sensing of regional-scale turbulent patterns in the atmosphere.

Statistical texture features are frequently used for the thematic processing of very high spatial resolution satellite images. The assessment of information content of 1st and 2nd order statistics is carried out based on processing WorldView-2 images of test areas located on the territory of the Savvatyevskoe forestry and employing the corresponding ground-based data. The comparison of the accuracy and computational efficiency of traditional and ensemble classifiers in the problem of pattern recognition of various natural and man-made objects reveals the high performance of the error correcting output codes method. The estimates obtained in this study demonstrate the advantage of using ensemble classification and 2nd order statistical texture features.

Neuromorphic computing, reconfigurable optical metamaterials that are operational over a wide spectral range, holographic and nonvolatile displays of extremely high resolution, integrated smart photonics, and many other applications need next-generation phase-change materials (PCMs) with better energy efficiency and wider temperature and spectral ranges to increase reliability compared to current flagship PCMs, such as Ge2Sb2Te5 or doped Sb2Te. Gallium tellurides are favorable compounds to achieve the necessary requirements because of their higher melting and crystallization temperatures, combined with low switching power and fast switching rate. Ga2Te3 and non-stoichiometric alloys appear to be atypical PCMs; they are characterized by regular tetrahedral structures and the absence of metavalent bonding. The sp3 gallium hybridization in cubic and amorphous Ga2Te3 is also different from conventional p-bonding in flagship PCMs, raising questions about its phase-change mechanism. Furthermore, gallium tellurides exhibit a number of unexpected and highly unusual phenomena, such as nanotectonic compression and viscosity anomalies just above their melting points. Using high-energy X-ray diffraction, supported by first-principles simulations, we will elucidate the atomic structure of amorphous Ga2Te5 PLD films, compare it with the crystal structure of tetragonal gallium pentatelluride, and investigate the electrical, optical, and thermal properties of these two materials to assess their potential for memory applications, among others. [ABSTRACT FROM AUTHOR]

This study investigates the occurrence and characteristics of low‐level jets (LLJs) up to 200 m above sea level in the North Sea area, specifically in the southernmost part of the basin, at the entrance of the English Channel. Using a short‐range Doppler lidar installed in Dunkerque Port, on the northern coast of France, wind profiles were recorded for 4 years and analyzed statistically. LLJs were detected on more than 11,000 of the 10‐min average wind profiles (5% of time), with similar jet core height and core speed distributions as in other sites in the southern North Sea area, and a similar annual cycle. However, there were differences in the core directions and the daily cycle, with afternoon northeastly jets being the most frequent in Dunkerque, whereas southwesterly nocturnal jets were dominant in the other North Sea sites. This suggests that wind channeling in the Dover Strait is likely a major factor for LLJ formation in Dunkerque region. The study also examined the conditions of LLJ occurrence using European Centre for Medium‐Range Weather Forecast (ECMWF) reanalysis v5 and ultrasonic anemometer data, but the different types of LLJs sharing the same core direction and occurrence conditions made it difficult to quantify specific jet formation mechanisms. This is the first experimental study on the North Sea shore, and at the entrance of the English Channel, providing valuable insights into the LLJ behavior in the region. [ABSTRACT FROM AUTHOR]

A method for automated processing high spatial resolution satellite images is proposed to retrieve inventory and bioproductivity parameters of forest stands. The method includes effective learning classifiers, inverse modeling, and regression modeling of the estimated parameters. Spectral and texture features are used to classify forest species. The results of test experiments for the selected area of Savvatievskoe forestry (Russia, Tver region) are presented. Accuracy estimates obtained using ground-based measurements demonstrate the effectiveness of using the proposed techniques to automate the process of updating information for the State Forest Inventory program of Russia.

We report on developments of the Geant4 electromagnetic physics sub-libraries of Geant4 release 10.4 and beyond. Modifications are introduced to the models of photoelectric effect, bremsstrahlung, gamma conversion, single and multiple scattering. The theory-based Goudsmit-Saunderson model of electron/positron multiple scattering has been recently reviewed and a new improved version, providing the most accurate results for scattering of electrons and positrons, was made available. The updated interfaces, models and configurations have already been integrated into LHC applications and may be useful for any type of simulations.

Antimony sesquisulfide Sb2S3 has become an outstanding advanced functional material in a variety of rapidly growing application fields: smart integrated photonics from the visible to telecom window, cost-efficient photovoltaics, energy storage and transformation. Rational design and tailoring of the required components need a deep insight into the atomic structure and dynamics of liquid and amorphous Sb2S3, but detailed information is missing in contrast to crystalline counterparts. Using high-energy X-ray diffraction and Raman spectroscopy over an extended temperature range, supported by first-principles simulations as well as by electrical and thermal studies, we show that the high optical and electric contrast between the SET (crystalline) and RESET (amorphous) logic states is related to the different short and intermediate range order in orthorhombic and vitreous Sb2S3. It includes strong asymmetry of the Sb–S nearest neighbor distances and a different coordination of antimony sites in the crystal vs. a distorted trigonal environment of defect octahedral SbS3 entities in glassy Sb2S3. A fast crystallization rate at elevated temperatures in liquid antimony sesquisulfide is related to the enhanced fragility, approaching that of telluride phase-change materials, and to a large fraction of ABAB squares (A: Sb; B: S), combined with a remarkable slowdown of the diffusion processes in the vicinity of the glass transition temperature, ensuring good retention of the amorphous state. Further improvements may be achieved using anionic (Se) or cationic (Bi) substitution that decreases the temperature of a semiconductor–metal transition and allows bandgap engineering, important for both photonics and photovoltaics. [ABSTRACT FROM AUTHOR]