Sergey V. Samsonov

1. Gaussian approximation results play a central role in modern machine learning, where algorithms are often implemented via stochastic approximation methods such as stochastic gradient descent (SG...

Despite a significant number of publications devoted to the biotropic effects of space weather factors, the psychotropic effects of heliogeophysical factors remain largely unexplored. Objective. To determine the psychological characteristics of female participants in the "Heliomed – 2" project living in mid-latitudes on one of its stages during the period of maximum solar activity, taking into account the psychological heliogeomagnetic synchronization identified in them. Materials and Methods. To achieve this objective, 13 female volunteers with an average age of 41.2 years (40.2–44.6) living in mid-latitudes were surveyed during the "Heliomed – 2" project in 2024 (a year of high-solar activity) using the C. Spielberger – J. Hanin questionnaire, E. Haim’s stress-coping behavior test, and S. Dellinger’s projective psychogeometric test; in addition, the integral indicator of heliogeomagnetic disturbance, the Kp-index, was determined. When comparing the daily measured indicators of reactive anxiety and the Kp-index, all subjects were divided into two groups: Group I – individuals possessing psychological heliogeomagnetic synchronization; Group II – individuals with no such synchronization. Results. It was found that at this stage, individuals in Group II (without heliogeophysical synchronization) predominated; compared to volunteers in Group I, they were more anxious, less effective in developing coping behaviors (primarily in the emotional and behavioral spheres), actively suppressed their emotions, engaged in self-blame, and sought to avoid emerging problems, therefore, they could be classified as a high-risk group for the development of psychosomatic disorders and cardiovascular events. Conclusion. Thus, when compared with the results of previous studies of volunteers at different latitudes and during different periods of solar activity, further research must take into account gender, latitude of residence, and solar cycle activity.

A pulse-periodic oscillation regime was experimentally obtained in a gyro-resonant backward-wave oscillator (BWO) with a feedback circuit providing a high (approximately 0.9) transmission coefficient. The experiments were conducted by a 30 GHz gyro-BWO with a working space in the form of a three-pass corrugated waveguide. The pulse repetition frequency, with duration of ~1.5 ns, was approximately 220 MHz. The observed regime is interpreted as a mode-locking effect in a ring resonator formed by the interaction space of the gyro-BWO and the feedback circuit.

In this paper, we present gfnx, a fast and scalable package for training and evaluating Generative Flow Networks (GFlowNets) written in JAX. gfnx provides an extensive set of environments and metrics for benchmarking, accompanied with single-file implementations of core objectives for training GFlowNets. We include synthetic hypergrids, multiple sequence generation environments with various editing regimes and particular reward designs for molecular generation, phylogenetic tree construction, Bayesian structure learning, and sampling from the Ising model energy. Across different tasks, gfnx achieves significant wall-clock speedups compared to Pytorch-based benchmarks (such as torchgfn library) and author implementations. For example, gfnx achieves up to 55 times speedup on CPU-based sequence generation environments, and up to 80 times speedup with the GPU-based Bayesian network structure learning setup. Our package provides a diverse set of benchmarks and aims to standardize empirical evaluation and accelerate research and applications of GFlowNets. The library is available on GitHub (https://github.com/d-tiapkin/gfnx) and on pypi (https://pypi.org/project/gfnx/). Documentation is available on https://gfnx.readthedocs.io.

The paper presents the results of the first experiments on the investigation of an inverted gyrotron or a gyrotron rectifier, a device which, unlike a conventional gyrotron, converts incident microwave power into direct current (DC) power. In the experiment, by means of cyclotron-resonance interaction with a thin solid initially rectilinear 8.4 keV/0.54 A electron beam, microwave radiation at a frequency of about 34 GHz with a power of 13 kW is converted by it into a power of 15 kW of a 70-μs pulse current that flows through a 51.4 kΩ resistor connecting the device collector to ground. The achieved efficiency of microwave-to-DC power conversion, taking into account the power to drive the electron beam, is 80%.