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This article discusses a method for analyzing the layered structure of soil using the phase-metric method of geoelectric monitoring to ensure the reliability of a railway track. The importance of monitoring soil layers for timely detection of changes that may affect the stability and safety of railway tracks is emphasized. The use of geophysical monitoring methods, such as phase monitoring of the geoelectric signals, allows us to optimize measures to strengthen the roadway and increase its durability. The present article describes laboratory experiments in which a specialized setup was created to simulate the process of drilling through various soil layers. Geoelectric methods involving the registration of phase characteristics of the electromagnetic field were used in an experimental setup. The experiments demonstrated the effectiveness of the phase-metric method for determining the characteristics of the layered structure of the soil. The results showed that the change in the phase of the signal recorded at the receiving electrodes can be used to identify different soil layers with different electrical characteristics, such as moisture and density. The method of modeling the physical and geological environment using equivalent circuits of elements in the form of a dielectric made it possible to more accurately analyze the electrical properties of the soil. Based on the obtained data, an automatic monitoring system was developed using recurrent neural networks (RNNs), in particular long short-term memory (LSTM) networks, for automatic detection of bends and transitions in signal time series. Evaluation of the model's effectiveness showed high accuracy in identifying layers, which contributes to increasing the reliability and efficiency of monitoring the condition of the railway track. [ABSTRACT FROM AUTHOR]

Assessment of the current state of the near-surface part of the geological environment and understanding of its layered structure play an important role in various scientific and applied fields. The presented work is devoted to the application of phasometric modifications of geoelectric control methods to solve the problem of the detailed complex study of the underground layers of the environment in the process of drilling operations with the use of special equipment. These studies are based on the analysis of variations in phase parameters and characteristics of an artificially excited multiphase electric field to assess poorly distinguishable details and changes in the layered structure of the medium. The proposed method has increased accuracy, sensitivity and noise proofness of measurements, which allows for extracting detailed information about the heterogeneity, composition and stratification of underground geological formations not only in the zone where the drill makes contact with the medium, but also in the entire control zone. This paper considers practical mathematical models of phase images for basic scenarios of drill penetration between the layers of the near-surface part of the geological medium with different characteristics, obtained by means of approximation apparatus based on continuous piecewise linear functions, and also suggests the use of modern machine learning methods for intelligent analysis of its structure. Studying the phase shifts in electrical signals during drilling highlights their value for understanding the dynamics of soil response to the process. The observed signal changes during the drilling cycle reveal in detail the heterogeneity in soil structure and its response to changes caused by drilling. The stability of phase shifts at the last stages of the process indicates a quasi-equilibrium state. The results make a significant contribution to geotechnical science by offering an improved approach to monitoring a layered structure without the need for deep drilling. [ABSTRACT FROM AUTHOR]

Flying ad-hoc networks (FANET) based on unmanned aerial vehicles (UAVs) and ground control systems is a convenient tool to collect data on the state of resources of agricultural facilities. Increasing the effectiveness of such network causes a need for new design of its radio transmitting equipment. Signal generators of radio transmitters of flying sensor networks and their spectral characteristics have been considered. In order to improve their spectral characteristics, the autocompensation principle has been applied. Block diagram and equivalent functional model of a carrier oscillator with automatic noise compensation have been shown. Transfer functions of the scheme for phase deviations of its various blocks have been obtained. Simulation had shown that the maximum degree of noise autocompensation reaches 13 dB, which confirms the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The near-surface subsoil area undergoes active changes as a result of antropogenic impact and natural factors. Effective use of geological environment necessitates control of the area, which is complicated by high noise level. The idea of phase-measuring geoelectric control method is based on tracking the phase changes of geoelectric signals and allows to detect low-level signals indistinguishable by well-known amplitude methods. Block diagram of the two-threshold phasometric control system of the geological environment was shown, as well as its operation principles and mathematic expressions. Matlab Simulink model of the geodynamic event detector circuit was developed. Dynamic mode simulation of the model was done, and the influence of the filter's parameters on the probability of successful geodynamic detection was estimated. The obtained results confirmed the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Flying ad-hoc networks (FANET) based on unmanned aerial vehicles (UAVs) are characterized by constant changed of the topology due to the moving of networking nodes. It causes an increased overhead costs for transmission of their coordinates when topology control is being done, or specific geographic routing protocols are being used. In order to reduce such overhead costs, a new approach based on medium access layer (MAC) adaptation is proposed. It evaluates the communication channel parameters, checks the integrity of the received data and manages retransmissions of information packets. Basic carrier sense multiple access/collision avoidance (CSMA/CA) MAC layer protocol for the application of neuro-fuzzy adaptation have been considered and the types of FANET service messages to be optimized have been described. A flowchart of the new MAC layer neuro-fuzzy adaptation algorithm was shown. Simulation of FANET performance with neuro-fuzzy MAC layer adaptation, as well as classic CSMA/CA protocol, was provided. The simulation showed that the modified MAC protocol reduces the number of lost packets while having a comparable transmission rate and average latency. Thus, the simulation showed the effectiveness of the proposed method of neurofuzzy adaptation of the channel level of the UAV network. [ABSTRACT FROM AUTHOR]

To optimize the rotation parameters of the drill and reduce the load on it during the drilling process, it is necessary to have information about the composition of the layers of the geological environment through which it passes. This information will reduce the wear of technical equipment and tools, as well as allow to plot optimal drilling trajectories and track the penetration of the drill into the target layer of the geological environment. This issue is especially relevant for the mining industry, where work is carried out at great depths with a complex structure of soil and rocks. Effective extraction of this information can be obtained by monitoring the phase changes of the recorded electrical signals from the receiving lines of the electrodes of the geoelectric monitoring system. The paper considers the general mechanism of implementation of the phasometric method in relation to the tasks of monitoring the drilling process, describes the equipment, as well as laboratory and field experiments to study the effectiveness of monitoring the drilling process by the phasometric method. The study of the dynamics of changes in the phase signals of the receiving lines of the electrodes during passage through the layers of soil with different electrical characteristics, which affects the change in the parameters of the recorded geoelectric signals. The research results are accompanied by graphic material confirming the possibilities of the proposed method and the prospects of its application in the extractive industry to optimize the parameters of drilling wells in real time. [ABSTRACT FROM AUTHOR]

Peltier thermoelectric modules (TEM) have several significant advantages over classic compressor-based cooling systems, such as better mass characteristics, non-dependence on special orientation, absence of moving parts, possibility of the precise temperature control over time, etc. In order to adjust different temperature regimes based on TEM, high quality automatic control systems are strongly needed. The development of such systems necessitates the use of complex models which take into account nonlinearities of the Peltier module itself, as well as different other blocks of the control system. The Functional diagram and model of the TEM-based climate control system have been represented. The transfer coefficients of nonlinear links and a scheme as a whole based on piecewise linear approximation have been obtained. A new methodology for modeling the nonlinear stability of climate control systems based on TEM under arbitrarily large impacting disturbances have been deleloped. The presented technique based on the Popov's frequency criterion and piecewise linear approximation allows an analytical study of absolute stability in general for any order of the model and with an arbitrary nonlinearities of components. Based on the proposed approach, Modeling of nonlinear stability of climate conltol systems based on TEM was done. As a result of the simulation, the stability areas of the system with various filters in the feedback loop were estimated. The possible application of the proposed approach in a future for optimization and synthesis of TEM control systems was briefly discussed. [ABSTRACT FROM AUTHOR]