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The article presents the results of optimization of the work process of a single-stage axial turbine in order to increase its efficiency. During optimization, it was necessary to preserve the construction of the original turbine as much as possible. To solve this problem, a parameterization scheme for turbine blades and path contours was developed, taking into account the design and technological limitations. The turbine nozzle blade had an inside baffle. To control the possibility of placing the baffle, a special program was developed that automatically monitors the spatial position of the sections of the blade of the nozzle set. A post-processing program was developed to control the flow parameters at the turbine outlet in height. The efficiency and the vertical deviation of the angle of the outflow from the turbine from the original one were used as optimization criteria. The limitations were the mass flow rate of the working fluid and the total pressure ratio of the turbine. The problem was solved in several stages with different changing variables. As a result of solving the problem, it was possible to increase the turbine efficiency by 0.9%

Introduction. The work is devoted to the calculation of series standards for the design of high-pressure transmission devices used in various hydra jet technologies, which will provide the design of these devices based on dimensionless indicators describing the relationship between their geometric and technological parameters.Materials and methods. The methodology includes the use of mathematical models and analytical approaches to assess the influence of various parameters on heat generation processes in equipment, as well as methods for statistical processing of results.Results. A histogram of temperature distribution was constructed and the data was approximated using the distribution curve of temperature values and parametric series were generated for dimensionless parameters depending on various factors such as temperature, pressure, rotational speed and linear speed. It is possible to obtain parametric series for linear dimensions from five temperature ranges and seven standard sizes depending on the pressure and rotation speed of the drill shaft.Discussion and conclusions. The results obtained provide a better definition of the relationships between rotation speed, geometric characteristics and temperature parameters through the use of dimensionless indicators and it is possible to optimize the design of such devices taking into account operating conditions and ensuring increased efficiency.

Digital simulation of mine fires and explosions is an important stage in the process of developing technical solutions and measures aimed at improving the safety of personnel involved in underground mining. Correct simulation results determine the effectiveness of decisions in the event of an actual emergency situation. In this regard, due attention should be paid to each stage of the simulation, and especially to the initial stage of model parameterization. This study formulates a general principle for determining the parameters of mine fire and explosion models, in order to assess their development using the AeroNetwork analytical package. Such parameters in the event of a fire are heat and gas (afterdamp) releases. In the event of an explosion, excessive pressure at the shock front in the explosion origin. It has been established that when simulating a fire, it is advisable to use equivalent heat and gas releases determined by the content of combustible components in the combustion origin. In the event of burning mining equipment, these parameters can be calculated on the basis of the technical characteristics of a machine. Furthermore, when simulating an unauthorized explosion of explosives, the excess pressure determined by the dimensionless length of the active combustion area is calculated taking into account the weight and specific heat of an explosive, as well as the geometric parameters of a mine working. When simulating an explosion of a methane-air mixture (firedamp), the excess pressure is calculated taking into account the gas content of rocks in terms of free combustible gases, the length of a blast cut, the size of the area of increased fracturing, and the lower explosive limit of methane. Based on the proposed principle of the parameterization of emergency models, as an example, a model of fire and explosion development in existing extended dead-end workings (more than 1000 m long) passing coaxially to each other at different heights was developed. The numerical simulation of different emergency situations in workings was carried out, taking into account performing mining in difficult mining conditions.

The article presents the theoretical substantiation of the author’s methodology for conducting a forensic linguistic examination of the text - parametric triangulation. Its essence is to attract to the previously verified method of parameterization the principles of triangulation - the use of several methods to solve one problem, as well as several sources when working with dictionaries and reference publications. The developed technique includes three consistent aspects of expert work: 1) the establishment of the parameters of identification of the offense committed in a verbal way; 2) determination of the list of methods and algorithm for studying language material in order to establish the compliance of its characteristics to the specified parameters; 3) quantitative-qualitative assessment of the results of the research. Practical issues of using the proposed methodology are considered in detail on the example of an expertise of speech activity products containing signs of insult. It has been established that based on the definition recorded in the Belarusian legislation, the insult is identified by the parameters of attributivity (status decrease in the image of the object of speech influence), non-normativity (the use of linguistic units related to the vocabulary as a part of the attributive constructions of the vocabulary) and deliberateness (In expert practice, most often replaced by factology), i.e., presence of intention to create a negative image of the victim. The conclusion on whether the conflictogenic text corresponds to one of the parameters is drawn from the results obtained through application of several methods: logical-and-semantic, lexiscentric and comparative analyses to identify attributivity; lexical, stylistic and genre analyses to identify non-normativity; syntactic, pragmalinguistic and contextual analyses to identify deliberateness (factology).Examples of the study of actual material are presented, including texts from the author’s practice of conducting judicial linguistic research. The relevance of the proposed methodology is proved by the achievement of a positive effect in the leveling of the possible subjectivity of expert conclusions and an increase in their level of visibility, as well as minimizing the assumption of inaccuracies in the conclusion of a specialist.

Introduction. Truss structures are widespread in construction due to a number of advantages, such as economy, versatility, and scalability. Accordingly, their modeling and calculation are urgent tasks in the design of building structures. Automatic solution to these problems causes an increase in design efficiency, calculation accuracy, and lower costs. The objective of the study is to examine the functionality and operation algorithm of the software module developed by the authors that generates the geometry of two-dimensional truss structures for subsequent modeling.Materials and Methods. Following the research of the widespread truss configurations, the classification of chords available in the software under consideration is given. The method of parameterizing a truss structure is provided. This method includes base geometric parameters of the structure such as dimensions, model construction rules, and additional features, as well as a comprehensive algorithm. The software is developed in JavaScript.Results. The software module has been integrated into a web application for calculating two-dimensional rod structures. To illustrate the functionality of the software, the examples of user interface are given as well as an example problem. The example includes configuration and calculation of an inclined truss structure. The results, such as support reactions and internal forces with axial force diagram, are provided.Discussion and Conclusions. Using this software module within the framework of the tool for calculating rod structures allows for the simplified process of modeling and calculating complex truss structures, design time, and resource reduction. The software module provides tools for specifying various types of structures, applying loads and assigning properties of a rod system, which makes it a useful instrument for design engineers.

The article discusses the computational procedure of the alternance optimization method as applied to the problem of semi-infinite programming. These problems are reduced numerous applied problems of optimization of objects with distributed and lumped parameters: robust parametric optimization of dynamic systems, parametric synthesis of control systems, etc. Since the calculation of alternance optimization method is rather difficult, as reduced to the solution, as a rule, the transcendental system of constitutive equations is proposed for efficient computational complexity of an embodiment of a computational procedure. To reduce the complexity of the computational procedure, the properties of the extremum points of the optimality criterion established in the alternance method are used in the region of permissible values of variables. These properties allow creating a topology of this area and thereby minimizing the number of references to it during the search procedure. The proposed computational method is especially effective for non-convex and nonsmooth optimality criteria, to which the technologically sound statements of semiinfinite optimization result. A step-by-step algorithm for preparing data and performing calculations, suitable for implementation in most programming languages, has been developed. The efficiency of the algorithm, which is higher, the larger the number of parameters included in the control vector and the higher the dimension of the optimization domain, is investigated. An estimate of the computational complexity of the computational procedure of the alternance optimization method is proposed, which makes it possible to determine the effectiveness of the application of the proposed algorithm for solving the problem of optimal control of the technological control object.

Introduction. The aim of the work is to develop a mathematical model of a part based on a parametric model of graphic systems. Material and Methods.The review of the status of the question of developing a mathematical model of a part based on graphic systems showed the possibility of controlling the geometric shape of a part through the variables of a parameterized drawing. A proposal was made to use design parameterization in the calculation of the parameters of technological processes in computer-aided design systems. Results. The article establishes links between the design parameters of the part drawing and tabular values of the variables. The revealed relationships between the parameters in the drawing and the variables in the table make it possible to change the geometric shape of the part by changing the values in the variable table, i.e. the drawing is managed through the table. It is proposed to use this system of work with the parametric drawing in computer-aided design systems for calculating the parameters of technological processes. Discussion and Conclusion. The tasks solved in this article allow making a step in increasing the level of automation of parameter calculations in computer-aided design systems. The implementation of the developed methodology for constructing mathematical models of parts based on graphic systems will increase the overall level of automation of developing geometric drawings of parts. The implementation of this technique in computer-aided design systems allows automating the calculation of parameters (cutting modes, time norms, technological dimensions on transitions, etc.).

The paper contains a substantiation of the method of parametric modeling used in forensic linguistics. An expert analysis procedure is described as an algorithm for evaluating texts using a closed list of parameters by standard formulas. Parametrization is the modeling of a process or phenomenon includes such items as features of a phenomenon (process), normative (prototypical) forms of each of the phenomenon features (process) manifestation, manifestation variation range which does not destroy phenomenon (process) identity. Legal risk parametrization in communication is carried out by building a parametric forensic-linguistic model of the offense. This model consists of the following components: the parameter code, parameters' list for identifying verbal offense signs, each parameter identifying verbal offense signs qualitative manifestations, each parameter identifying verbal offense signs quantitative manifestations, each parameter identifying offense verbal signs qualification indices, all identification parameters offense verbal signs indices qualification sum. A parametric model is developed on the appeal speech act example; it allows building an expert analysis algorithm that can be checked and reproduced. According to this model, we can observe the presense or the lack of linguistic offense signs under Art. 280 of the Russian Federation Criminal Code (public appeal for extremist activity). In the analysis of the call for one and verbal manifestations of extremism, a classification of calls based on the characteristics relevant to forensic linguistic expertise is proposed.

In the present study the effect of under ice warming is analyzed on the basis of observed data from the Karelian Isthmus and lakes of Karelia. A simple 1D parameterized mathematical model of the phenomenon was developed. The heat fluxes in the “ice – water column – sediments” system were quantified.

There are many different methods and tools for data analysis in dendrochronology. Modeling is one of them. One of the main issues in modeling is a choice of the main factors. Сlimatic data (temperature and precipitation) are the most common and affordable of them. Based on Vaganov – Shaskin model the new algorithm of visual parameterization of three-ring growth – VS-oscilloscope was developed. Algorithm was tested on different species of woody plants – Larix gmelini and Picea obovata. A new parameterization and analysis of modeling results help to evaluate conditions of area of growth of woody plants, based on dynamic of two climate variables: temperature and precipitation, without adding information about area of growth

The questions of speech and acoustic (registered on a human body at pronouncing by him of sounds) signals processing are examined. The measure of a distinguish ability for identification at parameterization of a biometric image by an amplitude-frequency response of a human body is developed.

Using the systems of non-adaptive control, in particular, modal for high-quality control over linear dynamic objects is discussed and some results of our research in this area are given in the paper. The primary objective of the study is to solve the problem of modal control synthesis for a multidimensional object based on the Van der Woyd's generalized approach, as well as on using the knowledge in the field of control, obtained from different sources, for the process of growing single crystals using the Czochralski method on the "GROWTH"-type setups. Using modern methods and tools for analyzing the properties of linear controllable systems leads to the need of using modal controllability of the system and solving the problem of synthesis of modal control over the multidimensional object. In the paper, generalization of the Van der Woyd's theorem in terms of band matrices for the case of MIMO-system modal control is given in the form of the algorithm, difference vectors of coefficients of specified and initial characteristic polynomials with respect to the growing process as the control object are described and parameterized. Using the graphical representation of the transfer characteristics of the object and closed-loop system in trajectory areas for analysis allows to obtain important information about the high-quality system control. It is proposed to use this method for increasing the dynamic quality of control over inertial objects, which is the process of growing crystals in order to increase the efficiency of control systems for modern growth setups in conditions of producing these crystals. The research results can be applied by specialists in the field of modal control over material, energy and information flows in control systems for modern technological processes, integrated into the technical environment of these processes [ABSTRACT FROM AUTHOR]