Simulation of the electroerosion treatment process using neural networks

The paper provides formalization and construction of a model of the process of electrical discharge machining. When describing the process, a T-shaped equivalent circuit containing an RLC circuit was used. Determine the transfer function of the proposed substitution scheme. Also, a task is formulated and an algorithm for neural network parametric identification of a T-shaped equivalent circuit is proposed. The problem is posed and an algorithm is developed for neural network parametric identification of the equivalent circuit with a computational experiment, the formation of training samples on its basis, and the subsequent training of dynamic and static neural networks used in the identification problem. The process was simulated in Simulink, Matlab package. Acceptable coincidence of the calculated data with the experimental ones showed that the proposed model of electrical discharge machining reflects real electromagnetic processes occurring in the interelectrode gap.

ALGORITHMIC SUPPORT FOR DECISION-MAKING ON THE EFFICIENCY OF OPERATION OF ABSORPTION AND REFRIGERATION PLANTS OF AMMONIA PRODUCTION

The features of the hardware and technological design of the AM-1360 series ammonia synthesis units operating in Ukraine are established, the main of which is the use of heat-using ammonia-water absorption and refrigeration units in the secondary condensation complex. The analysis of the functioning of the absorption and refrigeration units has been carried out. A significant dependence of their efficiency on external disturbances, such as temperature and humidity of atmospheric air, has been established. This causes significant fluctuations in the cooling temperature of the circulating gas in the evaporators of absorption-refrigeration units, which significantly affects the efficiency of ammonia production in general. Based on the results of the analysis of the existing information system, implemented on the basis of the TDC-3000 microprocessor complex, recommendations for its improvement were developed, the presence of which makes it possible to abandon daily analyzes and carry out only control ones to check measuring instruments. Algorithmic support has been developed, implemented in the MATLAB package and tested according to the data of industrial operation of absorption and refrigeration units of the ammonia synthesis unit. This allows the operator, in real production conditions, to obtain operational information on the numerical indicators of the efficiency of operation of absorption and refrigeration units, which characterize their operation to the greatest extent (circulation rate, cooling capacity, circulating gas cooling temperature and thermal coefficient) and make a decision on the possibility of reducing the cooling temperature. of circulation gas in evaporators by changing the frequency of circulation of solutions The created algorithmic software in the MATLAB environment allows embedding a client module, the so-called OPC client. The latter provides technology for free programming of access to current data.

Techno-economic aspects and problems of the rotary rowing units introduction in the modernization and construction of ships (on the example of projects 1809 and CNF11CPD)

The article contains a detailed analysis of studies related to the use of existing and new principles of fuel economy, and reducing the cost of re-equipment and operation of vessels of the above projects. The authors of the article did not set out to analyze the technical features of these projects. Only by linking to these projects, the analysis was done for the entire fleet of this type as a whole. A technical and economic analysis of the characteristics, modeling of the main and auxiliary installations in the Matlab package, providing fuel economy on the example of ships of projects 1809 and CNF11CPD, is carried out. Then a physical simulation was carried out. As a result of testing a vessel with a rotary rowing electric installation (RSEU), a qualitative analysis of the data obtained was carried out, conclusions were drawn that allow us to judge the possibility of large-scale use of such installations in maritime transport.

THE PROSPECTS OF USING THE MATLAB PACKAGE FOR MODELING LIGHTNING DISCHARGES IN POWER TRANSMITTING LINES

The possibilities of a simulation model of a power line section with a rated voltage of 220 kV created in the Matlab package under the influence of lightning discharges are described.

Determination of probabilistic characteristics of random values of estimates of the Lyapunov function when describing a physical process

The applied application of the Lyapunov characteristic function is determined by the properties of its estimates. Probabilistic characteristics of estimates of the Lyapunov characteristic function are described for the first time. The probabilistic characteristics of random values of estimates of the Lyapunov function are empirically estimated using statistical methods. The Matlab package has developed a model of a special device for obtaining estimates of the characteristic function by a direct method. A quasi-deterministic signal is fed to the input of the model, the instantaneous values of which are distributed according to the arcsine law, and an array of values of estimates of the Lyapunov function is obtained at the output, which is used to estimate the probabilistic characteristics of these estimates. Statistical estimation was performed by an indirect method. It is established that the values of the estimates of the Lyapunov characteristic function are distributed according to the normal law. The results of the research will be useful in engineering calculations, for example, when detecting message transmission errors in modems with a modulated characteristic function.

Development of algorithm for fuzzy art appraisal model

This paper presents an algorithm for a fuzzy art appraisal model, which is a hierarchical model based on a base price and the following adjustment. In the first step of the model, we determine the list of linguistic variables, their number, types of terms and types of membership functions for each term. Then, we analyze the subject area, process expert information and build a knowledge base containing 50 predicate rules of inference. The analysis shows that the model reflects a 4.37% error in a porcelain figurine appraisal. The paper also outlines recommendations on the implementation of the developed algorithm for fuzzy art appraisal model using Fuzzy Logic Toolbox for Matlab package and explains package limitations such as the need for strong authentication of art pieces, identification of mass artworks and a limited range of artwork that can be appraised.

FARCI: Fast and Robust Connectome Inference

The inference of neuronal connectome from large-scale neuronal activity recordings, such as two-photon Calcium imaging, represents an active area of research in computational neuroscience. In this work, we developed FARCI (Fast and Robust Connectome Inference), a MATLAB package for neuronal connectome inference from high-dimensional two-photon Calcium fluorescence data. We employed partial correlations as a measure of the functional association strength between pairs of neurons to reconstruct a neuronal connectome. We demonstrated using in silico datasets from the Neural Connectomics Challenge (NCC) and those generated using the state-of-the-art simulator of Neural Anatomy and Optimal Microscopy (NAOMi) that FARCI provides an accurate connectome and its performance is robust to network sizes, missing neurons, and noise levels. Moreover, FARCI is computationally efficient and highly scalable to large networks. In comparison with the best performing connectome inference algorithm in the NCC, Generalized Transfer Entropy (GTE), and Fluorescence Single Neuron and Network Analysis Package (FluoroSNNAP), FARCI produces more accurate networks over different network sizes, while providing significantly better computational speed and scaling.

Control System of a Robotic Irrigation Machine Based on the Mamdani Fuzzy Algorithm

The article analyzes the tasks that can be solved by agricultural robots. The purpose of the study was the robotization of the "Fregat" type crop irrigation machine by the fuzzy control of irrigation technological processes, which allows to control the irrigation rate. It is proposed to use in a robotic irrigation machine the analog valve-setter of the speed of the last cart, powered by electricity. It is recommended to include a diagnostic subsystem in the fuzzy control system of the flow control valve, which includes sensors for measuring the soil moisture and the slope of the irrigation machine in various areas of the field. The mathematical model of fuzzy control of the irrigation machine is developed based on the software control of the water supply depending on the terrain of the field, the speed of irrigation machine and soil moisture to reduce water consumption and improve the efficiency and quality of irrigation. The Mamdani algorithm, which is implemented in the MATLAB package, is proposed as a fuzzy inference system. The formalization of the description of the indicators of the irrigation machine is carried out by specifying linguistic variables. The proposed mathematical model can be used in the design of control systems for other robotic agricultural machines.

RiboDraw: semiautomated two-dimensional drawing of RNA tertiary structure diagrams

Publishing, discussing, envisioning, modeling, designing and experimentally determining RNA three-dimensional (3D) structures involve preparation of two-dimensional (2D) drawings that depict critical functional features of the subject molecules, such as noncanonical base pairs and protein contacts. Here, we describe RiboDraw, new software for crafting these drawings. We illustrate the features of RiboDraw by applying it to several RNAs, including the Escherichia coli tRNA-Phe, the P4–P6 domain of Tetrahymena ribozyme, a −1 ribosomal frameshift stimulation element from beet western yellows virus and the 5′ untranslated region of SARS-CoV-2. We show secondary structure diagrams of the 23S and 16S subunits of the E. coli ribosome that reflect noncanonical base pairs, ribosomal proteins and structural motifs, and that convey the relative positions of these critical features in 3D space. This software is a MATLAB package freely available at https://github.com/DasLab/RiboDraw.

Simulation of the movement of hedge cutter links in the Simulink application of the Matlab package

Simulation modeling allows researching a mechanism consisting of many links interacting with each other according to complex laws. In order not to write a model for each node of the investigated mechanism, it is advisable to use ready-made blocks of the Simulink application. To simplify the process of creating blocks responsible for the links of the mechanism, we used the Solidworks computer-aided design system. 3d models of each link were designed, kinematic connections between them were established. Thus, the mass characteristics of the links, their geometric parameters, moments of inertia and kinematic pairs were obtained. After exporting the model from the computer-aided design system to Simulink of the Matlab package, a basic block diagram was obtained which was supplemented with disturbing input signals, virtual oscilloscopes for characterizing, mechanical transmission units, etc. Based on the obtained coordinates of the frame links and the rotor knives, dependencies were constructed to determine the kinematics of their movement in three planes, which made it possible to clearly demonstrate the top and rear view of the mechanism under study in the considered time interval. The developed simulation model can be upgraded to study the dynamic characteristics of the mechanism.