The work analyzes the Power-Division Non-Orthogonal Multiple Access technology. An assessment is made of the influence of the error in estimating channel parameters on the probability of errors per symbol during the procedure for sequential elimination of interference on the receiving side and the throughput of the communication system. In order to improve the spectral efficiency of the communication system, expressions are derived to ensure fair allocation of power between users.

The stress-strain state of the piston of an internal combustion engine (ICE) and its components is studied using the method of contact interaction with a cylinder-piston group. To conduct the study, a marine four-cylinder four-stroke non-reversible cylinder engine without supercharging with a reversible gear transmission, a cylinder diameter of 85 mm and a piston stroke of 110 mm, 4HSP8.5/11 was used. An algorithm is derived that takes into account the deformations of the contacting parts. A technique has been developed for calculating the stressstrain state of a piston with oil-removing and compression rings. This method consists in solving systems of differential equations, which are represented by the relationship of various parameters of a solid deformable body.

The paper deals with the impact of measured channel state delays caused by subscriber movement and the delay-related effects of channel aging on the performance of DFT codebook precoding in a downstream multi-user MISO system. The channel estimate is obtained using the MMSE algorithm. The paper discusses a precoding algorithm based on codebooks and a method based on numerical optimization for calculating precoding weight vectors in order to increase the total spectral efficiency of a multi-user system.

To carry out numerical modeling, the QUADRIGA radio channel modeling package was used, which allows us to obtain the required volume of MISO channel implementations when subscribers move at different speeds. A comparison of the obtained precoding characteristics of the compared algorithms in a channel with movement of subscribers and the presence of spatial correlation is performed based on the distribution function of the average spectral efficiency over a set of users.

This article is devoted to the preprocessing of images obtained in poor visibility conditions. Phenomena such as fog or haze can significantly reduce the accuracy of neural networks designed to detect objects. Thus, preventing systems based on computer vision from functioning normally. In this work, an algorithm was implemented for automatic removal of static weather phenomena based on a bilateral filter. The algorithm was tested on a neural network trained to recognize road signs.

The article provides an overview of the results related to the search for integer graphs and related issues.

The article presents a new approach to risk management of emergency situations at cellular network base stations. The diversity of emergencies arising on heterogeneous equipment under the influence of various external factors makes risk management a critically important task. The novelty lies in the creation of a mathematical model that accounts for this diversity, providing more accurate and comprehensive prediction of emergency situations. The model is based on a Bayesian network and generates real-time solutions in the form of probabilities of emergency occurrences, identifying critical points and potential threats to the base station's overall functionality. This helps generate recommendations for reducing risks, identifying priority areas for implementing improvements, and modernizing equipment. To ensure effective interaction with the model, an API is being developed and studied using FastAPI and Python. The API interacts with the Bayesian model created in BayesFusion GeNIe. The model implements a new method for integrating the developed Bayesian network with existing applications based on REST API principles, thus introducing a new approach to risk management. The article describes the processes of API creation, performance testing, and deployment. As a result of using the API, real-time risk management becomes possible, helping operators prevent emergency situations.

The integrated model was developed for research purposes to monitor the risk landscape of cellular network base stations. The application of this model significantly increases the level of automation in the risk management process during the operation of cellular network base stations.

An algorithm for symbol synchronization based on complex envelope samples for DQPSK modulation is proposed. The algorithm does not use phase locked loop (PLL). The simulation of this algorithm is carried out, the average time of entering into synchronism and the probability of errors are determined.

During operation, various factors affect the fiber optic cable, which lead to failures. It is generally assumed that the weakest link in an optical cable is fiber, and therefore it is fiber failures that are considered in the article. The warranty period of the fiber, which is set by the manufacturer, is 25 years. Currently, on many sections of the routes where the optical cable is laid, its service life already exceeds the warranty period, and the question arises of replacing it with a new one. As a rule, the service life of an optical cable exceeds the warranty period, because the cable is subject to maintenance and repair during operation. This article proposes a method for calculating the degradation cycle of a fiber-optic cable, which determines the time of its replacement with a new one, taking into account the effect of gradual and sudden failures. The reason for the gradual failures is the aging of the optical cable and the increase in signal attenuation, resulting in a degradation failure (a decrease in the level of the received signal below the critical one), which leads to the replacement of the optical cable. The appearance of a sudden failure caused by outside interference is accompanied by repair work on connecting the cable at the breakage point. The appearance of each new connection leads to an additional attenuation of the signal and a reduction in the degradation cycle time. To detect sudden failures, periodic monitoring of the fiber technical condition is carried out. Within the framework of the proposed methodology, it is assumed that the degradation cycle of an optical cable is divided into degradation states of a certain duration, which, in turn, consist of intervals for checking the condition of the optical fiber in the cable. At the same time, mathematical models using semi-Markov processes are considered, reflecting the state of an optical cable during one testing period, in one degradation state, and on a degradation cycle. Expressions and dependencies have also been obtained showing how sudden and gradual failures affect the reduction of the duration of the opyical cable degradation cycle.