In the article, the authors note that current threats, challenges, risks and related global problems, and the urgent need for the use of renewable energy sources is coming to the fore in the life of modern societies. It is highlighted that there is a necessity to treat technological progress in correlation with modern science in Russian society, and it should be noted that nowadays the current policy in the field of ensuring climate agreements is subject to legal uncertainty. The authors conduct cognitive modeling and construct a cognitive model.
Keywords: global problems of modernity, information technologies, cognitive modeling, cyber operations
The paper considers the model of management of maintenance of the transport fleet of the territorial body of the Penal System of the Russian Federation. Using the theory of queuing, possible states of the system are identified, a graph of states is constructed, a system of differential equations describing the dynamics of the process under consideration is given, taking into account the application of the prioritization scheme when carrying out maintenance and repair of vehicles. In order to refine the model, it is proposed to use a neural network model (multilayer perceptron) to calculate the failure rates and restore special vehicles. Calculation formulas for the implementation of the learning algorithm of the considered artificial neural network by the method of error back propagation are given. The model proposed in the work can be used to build automated decision support systems in the field of operation and repairs, as well as to improve the material and technical support of institutions and bodies of the Penal System of the Russian Federation.
Keywords: maintenance, reliability, queuing system, multilayer perceptron, error back propagation method, special transport of the Penal System
A variant of the mathematical model of the problem of optimal cutting of a semi-infinite strip of material with the possibility of rotating the workpieces by 90 degrees is proposed. Two-dimensional blanks close to the shape of a rectangle or inscribed in a rectangle are considered. The process of recalculation of the basic sizes of blanks has been formalized. It is shown that the increments of the length and width of a rectangular blank can be determined in various ways. The developed mathematical models are mainly focused on solving the problems of small enterprises and the production of simple-shaped products. Recommendations on the software implementation of the cutting model are given.
Keywords: mathematical model, optimization, optimal cutting of a semi-infinite strip, rectangular workpieces, recalculation of the sizes of workpieces, rotation of workpieces by 90 degrees
A computer simulator for training operators of the technological process of granulating ammophos in a drum granulator dryer is considered. The technological object and the requirements for controlling the granulation process are briefly described. The functions of the simulator, the structure of its mathematical and algorithmic support are given. The software implementation of the simulator is made in the Visual Basic environment.
Keywords: computer simulator, mathematical model, algorithmic support, training of process operators, pelletizing, drum granulator dryer, granule diameter, ammophos pulp
The study of the problem of fretting damage to a mechanical assembly bolted in three dimensions requires the analysis of stress fields in Cartesian coordinates along the angle and radius of contact pads. It also requires determining the location of the crack initiation and propagation. In this study, we will focus on numerical simulation using ANSYS. The results obtained in the form of nodal solutions show in detail the positions of stress concentrations and the formation of the bolted assembly. The contact surface between plates (or contact elements) is characterized by contact pressure, adhesion and clearance. The results obtained made it possible to determine the stress that caused the initiation and propagation of a crack, as well as the position of the damaged area by fretting.
Keywords: bolt assembly, contact modeling, damage zone, fretting, Ramberg-Osgood law, Von Mises stresses
The paper discusses the use of machine learning in relation to natural language processing (sentiment analysis, semantic proximity analysis) to build a recommendation system for the choice of perfumery products. The topic of the work is relevant in view of the growth of the range of manufactured perfumery products and the complexity of its choice by consumers and promotion by manufacturers. The proposed approaches are relevant for solving this problem due to the accumulated textual reviews and reviews of perfumery products on various websites, including online stores.
Keywords: machine learning, natural language, sentiment analysis, distributive semantics, word2vec, recommender systems
The results of the analysis of leakage currents as a function of time in samples of polycrystalline ferroelectric ceramics solid solutions of lead titanate-zirconate with sodium and bismuth impurities under the condition of applying a constant electric field are presented. We considered batches of samples that were stored in different conditions, which led to the formation of two batches - standard and defective. The samples of the standard and defective batches differed in values of the dielectric loss tangent by several times, while other electrophysical parameters practically did not differ. To measure the patterns of current fluctuations with time in the sample, a modernized Mertz scheme was used. The electric field was changed stepwise on the sample. Current fluctuations at a constant voltage across the sample were measured during the establishment of a constant leakage current and were considered as a time series, allowing only a statistical description. Changes in the form of the dependence of the leakage current on time are determined with an increase in the electric field strength on samples with different values of the loss tangent. The exponential decline is accompanied by random jumps in the magnitude of the leakage current. It is assumed that at a higher voltage, the state of the domain regions stabilizes, resulting in current leakage under a depolarizing field, since the domain system retains its more rigid configuration.
Keywords: mobile robots, polarization, depolarization, ferroelectrics, polarization current, remanent polarization, dielectric losses, electrical load, domain structure, electrical breakdown, mechanical failure
The article deals with the solution of the problem of unilateral frictional contact on the example of an arched culvert in the embankment. Unilateral contact is modeled as a linear complementarity problem, which is solved using the Lemke method. The features of solving such problems are shown. A comparison with modern approaches is given, the advantages and disadvantages of the proposed method are indicated.
Keywords: constructive nonlinearity, frictional contact, unilateral constraints, linear complementarity problem, numerical models, finite element method, load increment
The article considers the possibility of using the ANSYS WORKBENCH software complex for calculating beams on an elastic base. The mechanical properties of the soil base are very complex, therefore, when calculating structures on an elastic foundation, mathematical difficulties arise. Thus, the task of improving calculation methods becomes extremely urgent. The use of computer modeling programs and the possibilities of modern computers allows you to get a more accurate solution to such problems. From using the ANSYS software package and the finite element method modeling of beam deformations on an elastic Winkler foundation was performed. The proposed method can be used to calculate the settlement of building and structures foundations
Keywords: ANSYS WORKBENCH, elastic foundation, beam, computer modelling, deformation, finite element method, Winkler hypothesis
The paper considers a model for managing the reliability of an intelligent video surveillance system of a protected object. To build a model of the operation of a security television system with video analytics modules, a scheme of a multiphase queuing system was used. The process of constructing a computer model for evaluating the quality indicators of processing information entering the system is described. The given computer model provides an opportunity to assess the reliability of the system in question in a wide range of parameters and can be used in the design, operation and modernization of intelligent video surveillance systems to increase their reliability and ensure the possibility of making effective management decisions.
Keywords: intelligent video surveillance, integrated security, reliability, multiphase queuing system, protected facilities of the Penal System
In a number of branches of agricultural production, including agriculture, land reclamation, etc., there are problems, the solution of which requires the use of artificial intelligence. In particular, the assessment of the reclamation state of agricultural fields in large areas is a very time-consuming task, even with the use of unmanned aerial vehicles. To automate these intelligent approaches, it is effective to use artificial neural networks (INS) implemented in the form of computer programs. The use of software as a service (SaaS) is a modern approach to computer support of various intelligent production processes, including agricultural. Agriculture is a promising industry for the introduction of such technologies. The aim of the study is to develop a methodology and create a cloud-based SaaS system for identifying defective areas of agricultural fields based on INS. The development of neural network technologies and cloud services makes it possible to process a large amount of information in the cloud and provide user access to computing power. The article describes the methodology of building a service architecture for recognizing problem areas of cultivated agricultural fields, data preparation, network training, development of client and server parts. Such implementation is possible with the use of such technologies and tools as CUDA, CNN, PyTorch. As a result, the strengths and weaknesses of their use for solving the problem of image recognition on the example of problem areas of agricultural fields were identified. It has been established that classification-type INS are capable of solving problems of recognizing the reclamation state of fields, and modern information technologies make it possible to transfer calculations to the cloud, while the cloud service can be monetized as a SaaS model.
Keywords: agriculture, color images, SaaS system, artificial neural network, image classification
Artificial intelligence methods can be used to solve the problems of agricultural production. Assessing the condition of crops in large areas, even with the use of unmanned aerial vehicles, is a time-consuming task. The peculiarities of the task of such an assessment are the multifactorial nature of the analyzed structures, which require the use of a systematic approach at all stages of the study from the formation of a database of color images to the intelligent solution of problems of their analysis. The results of the analysis of the U-net architecture of the INS and its limitations for the problem of image segmentation are presented. The purpose of the study is to substantiate the architecture of the segmentation artificial neural network (INS) to identify problem areas of agricultural fields. The hypothesis of the segmentation network advantage was tested on the DeepLabV3 ResNet50 architecture. Numerical experiments have established that the increase in the accuracy of segmentation of images of agricultural fields is constrained by the limited resolution and accuracy of manual markup dataset. The built architectures can be used as an algorithmic core for creating SaaS systems, while the performance of the used configuration of the INS can be crucial.
Keywords: color images, segmentation task, agropole plots, deep neural network, INS architecture, convolutional layers
The application of the results of hardness measurements and its modeling in CAD as a 3D model is considered. Different welding modes were applied and electrodes CT-15, OZL-8 and CL-11 were used as consumables. The test material is a hot-rolled pipe with a diameter of 159 mm made of corrosion-resistant steel 12X18N10T with a thickness of 6 mm. The electrodes were fused to half its length and removed from the electrode holder, after cooling the remainder of the electrode, it was reused. For scanning measurement of microhardness of samples with a load of 100 g, the scanning step was applied 0.5 mm. The use of modern software was able to more accurately simulate the test results on a 3D model. The samples are welded with CT-15 electrodes at a maximum current of 100 A. the hardness is over 450-550 HV, regardless of what the passage was. Similarly, when welding with OZL-8 brand electrodes, but only at low currents, the hardness exceeds 450 HV. In both electrodes, the hardness is increased. When using OZL-8 electrodes, samples welded at high currents have less hardness than at low currents. When welding with these electrodes, it is possible to use them in certain passages, for example, when surfacing the root layer of the seam. In the case of full penetration in high-current modes with CT-15 electrodes, the result differs little as in low modes.
Keywords: steel 12X18N10T, multi-pass welding, welding of austenitic steels, pipe, coated electrodes, welding modes, mechanical properties, macrostructure. Excel, Autodesk Inventor, CT-15, OZL-8, CL-11, amperage
The paper considers a model of security equipment reliability management using optimal control methods and data mining. An algorithm is given for finding a maintenance and repair management strategy that provides decision support in a wide range of system parameters changes. The possibility of automating the search for optimal solutions to the problem of increasing the reliability of security equipment is investigated on the example of the information system of analysis and predictive diagnostics of technical objects of the IS "Analyst", and the prospects for the use of neurofeedback in the tasks of increasing the reliability of complex technical systems are considered.
Keywords: security system, reliability of technical systems, optimal control, necessary conditions of optimality, neurofeedback
The widespread use of Educational Data Mining (EDM) allows the collection of data in the educational field for the analysis and adjustment of the educational process. Based on the analysis of the areas of training of construction specialties, a choice of job requests from the site was made hh.ru . A chain of nodes has been built in the Knime program for analyzing vacancies in construction specialties. Based on Knime queries, a semantic analysis of employers' requirements for construction specialties was carried out. The dependence of the result of the analysis of employers' requirements on the number of terms in the topic was considered. The preparation of the material was carried out to compare the data obtained from the work programs with the data extracted from the job search site hh.ru .
Keywords: analysis, data, work program, education, query, term, table, employer requirement
This article discusses the problems of constructing convolutional neural networks for determining road objects. The general relevance and formulation of the problem of determining road objects is presented. The rationale for the use of artificial neural networks for determining road objects has been formed. The Retinanet network architecture is used as the main architecture of an artificial neural network for determining road objects. The general concept of this architecture and the main subnets are visualized. Error functions for the main subnets of the Retina net network are described. The design description of algorithms for constructing data annotation for training an artificial neural network, as well as algorithms for constructing the neural network architecture of classification, regression and feature pyramid is given. The dynamics of changes in the general error function when determining road objects is determined. The result of training an artificial neural network is presented.
Keywords: convolutional neural networks, classification, regression, convolutional neural networks, deep learning, big data, mathematical modeling, computer science, RetinaNet architecture
The work is devoted to the analysis of the frequency characteristics of a piecewise homogeneous coaxial Bragg microwave structure with irregularities in the inner conductor. The article presents varieties of piecewise-homogeneous Bragg coaxial microwave structures, their options for practical application and implementation, as well as the possibility of their modernization, and also considers a recurrent method for calculating a piecewise-homogeneous transmission line. The possibility of using lumped capacitances in an equivalent circuit is considered and simulation is carried out in the electrodynamic simulation program with initial parameters.Based on the results of the work done, it was concluded that the effect of lumped capacitances included in the equivalent circuit of a piecewise homogeneous coaxial Bragg microwave structure significantly improves the frequency characteristics of a single-wave calculation in comparison with full-wave simulation. When approaching conditions favorable for the propagation of the first highest mode, it is necessary to include the effects of its propagation in the calculation.
Keywords: Bragg microwave structure, reactivity, permittivity, coaxial cable, microwave range
The article represents the results of the research of economic effectiveness of NIIOKR results. There are investigated the possibilities of using mathematic models for the evaluation of scientific production, the opportunities of its introduction into the economic practice.
Keywords: mathematic models, prognosis, economic effectiveness, economically valuable features, sorts
Temperature regimes of heating and cooling in three-dimensional printing are the most significant part of the technological solution in the production of products in any industry: from printing parts for aviation and rocket engineering to the construction of buildings or the manufacture of prosthetic human bones. The paper considers a simple and reliable method for obtaining calculated values of non-stationary temperatures and heat fluxes during layer-by-layer printing of products with various thermophysical properties and imperfect contact between layers, which does not require special software shells and large machine resources for calculations.
Keywords: non-stationary heat transfer, multilayer printing of products, additive manufacturing, 3D printing of products, heating and cooling of multilayer products, layer-by-layer deposition, optimization of the temperature regime of printing products
The paper considers a model for managing the reliability of a data transmission network used by an executive authority to organize access to state information resources. The process of constructing a computer model of the system for assessing the availability factor is described. The constructed computer model provides an opportunity to assess the reliability of the system in question in a wide range of parameters and can be used in the design, operation and modernization of the organization's information and telecommunications network to increase its reliability.
Keywords: information and telecommunication network, provider, routing, reliability, state information resource
In the process of conducting information activities, a large set of data accumulates, which reflects the specific features of the work performed. The stored information is not always in an orderly and understandable form, which makes it very difficult to work with it. This complicates the analysis, increases the processing time. Neural networks can solve this problem. Today, neural networks are widely used in many fields of activity, due to their application, for example, it becomes possible to analyze the market situation more thoroughly and make appropriate decisions that directly affect success. Thanks to the use of a neural network, it is possible to carry out a set of information in a convenient form for analysis. The article will provide a list of information about the self-organizing Kohonen map, concerning the principles of the neural network. The processing of test data with visualization of maps is considered.
Keywords: Kohonen self-organizing map, Kohonen networks, neural networks, cluster, processing, Self Organizing Map, SOM
The task of planning the trajectory of a mobile robot is considered in the following formulation: it is necessary to choose the optimal trajectory of the robot's movement over hilly terrain from one point to another among the many available paths. The developed algorithm for planning the optimal trajectory of movement of mobile objects allows minimizing energy costs when moving over hilly terrain. The optimal trajectory is determined from the condition of minimum of the functional of the rolling friction forces work. To find the optimal trajectory on which the friction forces work is minimal, is used the dynamic programming method. The proposed algorithm for planning the optimal trajectory can be used to reduce energy consumption in the process of moving over hilly terrain not only autonomous robotic systems, but also other vehicles.
Keywords: planning algorithms, rolling friction force operation, dynamic programming, optimization according to the selected criterion
The article examines the issue of calculating the depth of compression stresses when using a spherical indenter in order to increase the fatigue strength of steel parts. When the spherical indenter is pressed, elastic deformation of the surface first occurs, and then plastic one. The residual plastic deformation is expressed in the size of the print. The physicomechanical properties of the processed material are not taken into account, the process of pressing a spherical indenter into a steel sample in the ANSYS program is modeled by the final element analysis (FEA).A bilinear deformation diagram was fed, which is set in the program by the modulus of elasticity, yield strength and Poisson's ratio. At the next stage, a finite element grid was generated by using the Hex Dominant Method, which divided the model into elements in the form of hexahedra of various sizes. In the contact area, the size of the finite elements was 0.2 mm. The results of calculations of analytical and numerical methods for spherical indenter diameters of 4, 6, 8, 10 mm and various degrees of plastic deformation to determine the depth of compression stresses are presented, compared with known data, the error is calculated. A dependence is derived for a preliminary assessment of the occurrence of residual stresses depending on the diameter of the well after the indentation of the spherical indenter.
Keywords: spherical indenter, bilinear deformation diagram, plastic deformation, indentation depth, compression stress
The article uses the mathematical apparatus of the theory of linear-quadratic differential games, as well as the method of qualitatively representative scenarios to build a mathematical model of interaction between the university and its industrial partner. The analytical solution of the game (Nash equilibrium) is obtained and the numerical solution of the problem is demonstrated.
Keywords: linear-quadratic differential games, optimization, mathematical modeling, method of qualitatively representative scenarios, game theory
Keywords: search engine, document analysis, linguistics, word forms, morphology, word generation, web service