Software & Systems

Articles of journal № 3 at 2022 year.

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11. Boundary values evaluation for average response time to an information system user request [№3 за 2022 год]
Authors: Shelest M.N. , Tatarnikova, T.M.
Visitors: 1295
The paper proposes methods for estimating the upper and lower bounds of the average response time of large information systems to a user request. A user request is a transaction consisting of a sequence of commands for which computing re-sources are reserved. The transaction is formalized as a route, which is a chain of “server-buffer” pairs, their number is equal to the number of transaction commands. At the same time, the service device is a mean of executing transaction commands; the buffer is a memory for fixing the results of executing transaction commands and waiting for the time to arrive for service. Allocation of loosely coupled route groups allows parallel processing of transactions. The authors propose a mathematical scheme of a large information system that organizes transac-tion routes in the form of a queuing network, so that each user request passes a certain route from the service devices. The method for estimating the upper bound on the average response time of the system to a user request is based on adding redundant dependencies and duplicating some service nodes. The method for estimating the lower bound of the average response time of the system to a user request is based on the removal of serving nodes that play the role of a weak connection between neighboring routes of the queuing network. The proposed methods allow selecting such parameters that meet the requirements for the infor-mation system being developed and, accordingly, meet the indicators of the quality of service for users of information systems.

12. Applying artificial neural networks in automatic control systems for magnetic levitation [№3 за 2022 год]
Author: Korobeynikov, A.G.
Visitors: 2203
This paper considers the problem of neural network identification in the automatic control system for magnetic levitation (neural network controller). This problem is due to the fact that at present, it is typ-ical to use a mathematical apparatus based on artificial neural networks when designing automatic con-trol systems for complex technical dynamic objects. Such networks have the following unique ad-vantages: the possibility of parallel computing; finding previously unknown relationships between in-put and output sequences of digital signals; more efficient control of nonlinear systems using nonlinear activation functions. In addition, the use of artificial neural networks sometimes removes the difficul-ties that arise when describing some problems in the form of analytical mathematical models. This paper describes the solution for the problem based on artificial intelligence methods – well-known recurrent artificial neural networks NARX and LSTM. These networks were trained using the backpropagation algorithm and the Levenberg–Marquardt method, which have good convergence. For this problem, the application of trained artificial neural networks to test data has shown some ad-vantage of the NARX network compared to LSTM. Moreover, the RSME rms error for the NARX net-work with 50 hidden layers for this problem is less than for the network with 100 hidden layers. The MATLAB R2021b system was a tool for setting the architecture of neural networks, their con-struction, training and testing. The obtained results are applied in designing automatic control systems for levitating objects. Currently, most of these systems are being developed and used to transport goods for various purposes using the effect of magnetic levitation.

13. Applying CUDA technology for training the Kohonen neural network [№3 за 2022 год]
Authors: Latypova D.S., Tumakov D.N.
Visitors: 3062
The paper presents clustering of the data from in the training samples of the MNIST and Fashion MNIST databases. For clustering, the authors use a Kohonen neural network with a Euclidean metric for estimating distances. The optimal number of clusters (no more than 50) is determined for each handwritten digit (MNIST) and type of clothing (Fashion MNIST). Neural network training is parallelized on a NVidia graphics device using CUDA technology. There are the results for each digit illustrating the comparison of the processor and GPU operating time. For both the digits and clothing types, there is a conclusion about a 17-fold acceleration on an entry-level gaming laptop. Test samples of the same databases are used to verify the cluster construction correct-ness. For both sequential and parallel learning, it is concluded that the vectors from the test sample be-long to the correct cluster with a probability of more than 90 % in the case of handwritten digits. In ad-dition, there are calculated F-measures for each digit and type of clothing to evaluate clusters. It is shown that sequential and parallel clustering give similar results. The best values of the F-measure are obtained for the digits 0 and 1 (F-mean is 0.974), while the worst value is obtained for the digit 9 (F-mean is 0.903). For the Fashion MNIST data, the best value for the F-measure was obtained for trousers (F-average value is 0.96), and the worst value was for a shirt (F-average value is 0.34). De-spite the large variations for the F-metric values of the considered two databases, the differences in the clustering results are minimal. Thus, the maximum difference of the F-measure is about 0.01 for the MNIST and about 0.04 for the Fashion MNIST.

14. Forecasting based on the second generation artificial neural network for decision support in especially significant situations [№3 за 2022 год]
Authors: E.V. Palchevsky, Antonov V.V. , Enikeev R.R.
Visitors: 2611
Nowadays, specialized system models implemented on the basis of decision support in exceptional (emergency) situations (states) using machine learning, artificial intelligence (including using neural networks) to reproduce, predict and prevent (or minimize risk) consequences) in exceptional situations are useful and becoming increasingly popular. Floods also fall under such exceptional situations and states. Therefore, there arises the problem of early forecasting of an exceptional situation using the ex-ample of rising water levels at stationary hydrological posts in order to prevent (or minimize the risk) the transition of the system under consideration into an exceptional state (emergency situation). To solve this problem, the authors propose a decision support system for early forecasting water rise levels. It is based on a neural network (intelligent) analysis of retrospective data (code of a station-ary hydrological station / automatic station, date, water level at a stationary hydrological station / au-tomatic station, atmospheric pressure, wind speed, snow cover thickness, amount of precipitation, time and air temperature) in order to calculate the values of water levels for 5 days in advance. The artificial neural network itself is based on the freely distributed TensorFlow machine learning software library; a modified backpropagation method is used as training. Its main difference is the addition of an artificial neural network (ANN) learning rate increase factor. An analysis of the effectiveness of the proposed solution in the framework of forecasting the flood situation has shown high accuracy in calculating the forecast values of water levels: the difference be-tween the real and predicted values is 2.10 %. This will allow specialized services to carry out special-ized anti-flood measures in advance (5 days in advance). Thus, information support during special situations is an absolute (not relative) indicator of data quality that allows developing and making decisions in the framework of predicting possible critical situations and preventing the transfer of the state of the territory management system to critical situa-tions.

15. Forecasting technological trends based on the heterogeneous data analysis [№3 за 2022 год]
Authors: Nguyen Thanh Viet , Kravets A.G.
Visitors: 2017
To achieve competitiveness, enterprises need to exploit a development strategy by forecasting promis-ing technologies using limited resources. Numerous previous studies have shown that unexpected changes in R&D and patenting of intellectual property are associated with large changes in the market value of an enterprise. In fact, there is a strong correlation between the volatility of market shares, stock prices in the early stages of high-tech enterprise development, and the period when the innova-tive technology is not yet defined. Thus, we propose that if company's share prices continue to trend upward, then the developed technologies are likely to become promising innovations in the future. This paper proposes a method for forecasting technology trends by analyzing web news to identify high-tech enterprises, predicting stock price trends for selected enterprises and analyzing the clusters of patent applications. Unlike other studies, our method advances the idea of predicting technology trends by forecasting the stock price trend using univariate and multivariate data preparation ap-proaches, and using Bayesian optimization to explore the best hyperparameters for machine and deep learning models. The study uses the developed software system for analyzing word frequency burst detection and stock price prediction. In particular, the proposed method is adopted to predict the price dynamics of Tesla and Samsung shares as case studies.

16. A software package for simulating a silicon hydrochlorination reactor [№3 за 2022 год]
Authors: Glushkov I.V. , Chistyakova T.B. , Averina Yu.M.
Visitors: 2029
The modern development of industrial enterprises is impossible without introducing information tech-nologies (IT) into the process of their functioning. The IT introduction allows increasing the competi-tiveness of industrial enterprises. In a market economy, process management involves a range of dif-ferent risks. These risks can be modeled using software packages. In the article, the subject of research is the technology of developing a software complex for the reactor for the hydrochlorination of ground sili-con operating in dynamic mode. In this work, for the first time at the software level, the main features of the operation of the trichlorosilane synthesis reactor are proposed and shown. Described is material and heat balance of reactor, hydrodynamics of "suspended" layer is shown and visualized. Hydrody-namic and thermal calculations of the synthesis reactor were carried out. These calculations are inter-preted into a mathematical graph. A mathematical apparatus for describing the operating parameters of the reactor is shown and for the first time a computer mathematical model of the process of synthesis of trichlorosilane of active production has been developed. The technological processes of the study object were visualized. Sys-tem of monitoring, control and regulation of reactor operating parameters to ensure safety of produc-tion is proposed. Monitoring and control devices are connected to mathematical model. With the help of the resulting software model, various experiments can be carried out in "real time". The study has established the importance of maintaining the operating conditions of such reactors, re-lated to the possibility of local overheating zones that may affect the occurrence of emergencies. The work is of interest to specialists serving the production of trichlorosilane and is aimed at reduc-ing the technological risks arising during the operation of the reactor.

17. Developing a password generator using GUI MATLAB [№3 за 2022 год]
Authors: Shchukarev, I.A. , Markova E.V.
Visitors: 2173
Nowadays, in most cases accounts of various sites, portals and cloud storages have weak passwords. In addition, the passwords created by users themselves are of insufficient length, which directly affects their reliability. Therefore, first of all it is necessary to create sufficiently complex and long passwords to ensure account security. In this paper, the authors present a developed a graphical computer application that allows automat-ic generating of passwords with custom settings and displaying the result in the appropriate field. The created passwords are almost impossible to guess since they include a combination of random upper and lower case letters of the English alphabet, numbers and special service characters. The authors im-plement the ability to change the password length, to output the result to the program window and save it to a separate text file named parol.txt. This application and the entire graphical user interface are not written in a specialized programming language, such as Python or C++, which is typical for programs of this type, but in the MATLAB tech-nical calculation environment using the MATLAB GUI and MATLAB Compiler SDK. The MATLAB Compiler SDK capabilities made it possible to create a standalone exe application, not an m-file, which is the MATLAB program internal format and works only if there is fully installed MATLAB environ-ment. To make it convenient for the end user, the program is designed as a stand-alone graphical appli-cation that can run on any computer with MATLAB Runtime installation that allows running compiled applications on systems without the installed MATLAB. The program is built using MATLAB GUI and MATLAB Compiler SDK. As a result, this application can be used by organizations with a network se-curity department, as it can facilitate the creation of many new random passwords for a large number of computers and employee accounts.

18. Developing an information system in the field of composite materials using modern tools [№3 за 2022 год]
Authors: Kirillov N.D., Koltsova E.M.
Visitors: 1561
The article considers the approach to developing an information system in the field of composite mate-rials using the modern development framework Laravel in the PHP programming language. This study includes the subject area analysis and data storage model development based on this analysis, the de-velopment of the main program modules of the system and the implementation of the logic of interac-tion between these modules. The originality of the study is in the implementation of the information system as a web-based service for quick and easy access to information based on the Laravel develop-ment framework. This paper identifies and compiles a list of the main entities that describe the field of composite ma-terials. Then, the paper presents a description a method of compiling and developing a relational data storage model for these entities. During model developing, among other things, the authors used meth-ods for the most optimal storage of hierarchical data structures. Based on this data storage model, the authors developed modules and blocks of information system modules and connected these modules into a single end service. This service is web-based and can very conveniently provide users and re-searchers of composite materials with access to all the information they need. The work notes and de-scribes the tools and modules of the Laravel framework, which were used in the development of the en-tire system. As a demonstration of the study results, the authors give examples of the information system opera-tion - the authorization pages of a web-based service and some pages of the main entities of the system are given as an example of service visualization.

19. Information system for calculation, information accumulation and certification of phosphorite thermophysical properties [№3 за 2022 год]
Authors: Orekhov V.A. , Bobkov V.I., S.V. Panchenko
Visitors: 2009
The paper proposes creating a certificate of phosphorite properties, which allows preserving in elec-tronic form experimental temperature dependencies of the material thermal conductivity coefficient at its first heating and in the annealed state, specific true heat capacity at the first and second heating, ef-fective heat capacity at the first heating, relative linear expansion, electrical conductivity and density of phosphate material at heating. There is a developed an information system that can implement such certificate of properties. It al-lows inputting and storing data on chemical composition and thermophysical and technological proper-ties of samples in digital form, searching and processing them. This system uses client-server technolo-gy to access and process data. Calculation of thermophysical properties of phosphorites by structural models takes into account hierarchical properties of phosphorite components, their volume and mass fractions. The information for determining the component proportions is the material mineralogical composition. The information system includes a program for calculating a thermal conductivity coefficient and a specific heat capacity. It differs by taking into account mass and volume fractions of the main rock-forming minerals using interpolation of table temperature values of thermal conductivity coefficients and specific heat capacities of phosphorite, carbonate and silica to determine thermophysical proper-ties of the components at any temperature. The thermal conductivity coefficient of the material is cal-culated is based on the combined thermal conductivity model taking into account the endothermic re-action of carbonate dissociation; the specific heat capacity is calculated from the additive model. There is a developed algorithm for a program for calculating thermophysical properties by the chemical composition of phosphorites.

20. Developing software for mathematical modeling of temperature distribution in the process of electron beam welding [№3 за 2022 год]
Authors: S.O. Kurashkin , Rogova D.V., Tynchenko V.S., Shutkina E.V.
Visitors: 2083
The purpose of the study is to develop a software system for modeling temperature distribution in the electron-beam welding process (EBW) in the Embarcadero RAD Studio application (student version), in the programming language C++. The base for this development is the thermal field theory using mathematical models to calculate the surface temperature distribution. Nowadays, it is possible to carry out simulation in the numerical simulation environments Comsol and ANSYS, as well as in the MATLAB package. These programs are powerful solutions, however they have a number of significant drawbacks such as: the need to create a product sketch in CAD systems and programming calculation models in the Comsol and ANSYS packages; direct work with the source code in the modeling process and lengthy calculations in the MATLAB package. Thus, the authors propose developing a software system based on mathematical models that will al-low: (1) simulating the EBW welding process for products from different alloys considering their geo-metric dimensions and thermophysical parameters, which will make it possible to determine the opti-mal technological parameters and, therefore, eliminate root defects; (2) simplifying the process of ELW modeling comparing to such systems as MATLAB, ANSYS and Comsol. The paper describes a software system for modeling temperature distribution, an algorithm for mod-eling an experiment, and an algorithm for calculating temperature. In addition, there is a presented modeling process using data based on full-scale experiments (technological parameters, thermophysi-cal parameters and geometric dimensions of the product). In addition, the developed software system allows storing both the results of the developed technological process and the simulation results. Introduction to production of the proposed approach to modeling the process of electron beam welding for thin-walled structures will reduce material and labor costs when developing the technolog-ical process of electron beam welding, as well as when introducing new types of products into produc-tion.

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