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  • Methodology and algorithm for express assessment of the state of complex technical systems. Constructive approach

    Assessment of the technical condition (hereinafter TC) of technical systems is a prerequisite for a modern strategy for their operation. The study of new methods and algorithms that provide express assessments of the condition of technical devices and reduce the subjective component in these assessments is an urgent and in demand task. The paper presents a constructive approach to assessing the TC indicators of complex technical systems based on a modified method of analyzing hierarchies and the TC index (hereinafter referred to as ITS) of equipment, which is determined on the basis of weights and ITS of the main components of the equipment in question. The ITS of the main nodes is calculated based on the comparative characteristics of the operating parameters of the equipment during its operation, and the weights of the nodes are determined based on the methods of the matrix of paired comparisons (Saaty method) and the degree of importance of the line (DIL - Degree Importance Line method). The testing of the methodology and algorithms in this study was carried out on the basis of statistical data from a NASA turbojet engine (hereinafter referred to as turbofan engine), published in 2008.

    Keywords: technical condition, technical condition index, complex technical system, maintenance and repair, hierarchy analysis method, DIL method, constructive method for assessing technical condition, algorithm for express assessment of technical condition

  • Stress-strain state of a triangular membrane panel under the action of various types of lateral loads

    The article contains the methodology and results of theoretical and experimental studies of the stress-strain state of a conical radial-beam dome with triangular shell elements. The results obtained by various methods are analyzed and compared. The triangular membrane panel is part of the radial beam dome structure and consists of a support frame and a steel membrane in the shape of a triangle. The shape of the triangle forming the membrane panel can be different and depends on the number of ribs in the radial beam dome. The supporting contour is a compressed-bending element of the dome and is made, as a rule, from a rolled steel profile with a channel section. The membrane is made of thin steel sheet and attached to the upper flange of the channel with self-tapping screws or spot welding. To assess the strength and deformability of a steel membrane sheet, its operation under the action of a uniformly distributed snow load, an unevenly distributed snow load and a concentrated installation load was considered. Several options for nonlinear static calculations in various computer systems are shown.

    Keywords: building structures, wooden structures, membrane panel, stress-strain state, radial beam dome, dome, membrane, design, experimental study

  • Selecting a converter of aerodynamic forces and moments into the trajectory of motion for Simulink flight models of aircraft

    The article explores the problem of creating aircraft flight models in the Simulink environment. The reference systems in which transformations are carried out are considered. The equations of motion used in the simplest converters are given. The initial conditions for the equations are determined: the speed of the body, the angular orientation of the body's pitch position, the angle between the velocity vector and the body, the speed of rotation of the body, the initial position, the mass and inertia of the body, the source of gravity, the acceleration due to gravity, the curb and total mass of the body, speed of air flow, inertia of an empty and full body, flight trajectory, etc. An analysis of converters of aerodynamic forces and moments into the trajectory of motion as part of an aerospace package in the Simulink environment was carried out. Recommendations are given for their use for various modeling purposes. The results of modeling a simple converter with three degrees of freedom are presented.

    Keywords: modeling, MatLab, Simulink, equations of motion, aerodynamic torque, flight path, coordinate transformations, reference system, degrees of freedom

  • Identify and rank threats at a critical government facility

    The article discusses the issues of identifying and ranking threats at an important government facility. The classification of threats by type is described. The article discusses the concepts of “design-based threats” and “the most dangerous variant of the violator’s actions” and their differences. An example of ranking threats and reducing their number to reduce the dimensionality of the vulnerability analysis problem is considered. An important government object is considered as an object in the example. Experts are tasked with ranking threats according to the level of potential losses for an important government facility if they are realized. In practice, the implementation of an accepted design threat may lead to lower potential losses than the most dangerous option for violators and, as a result, to lower requirements for the effectiveness of the physical protection system.

    Keywords: comprehensive security, methods, models, security forces, intruders, important government facilities, clashes between security forces and attacks, ranking of threats

  • On the variant of formalization of the task of extracting key skills and cluster analysis of vacancies in the implementation of a comprehensive digital career guidance toolkit

    The article proposes a general formalized model of the task of processing and extracting potential key skills from job descriptions to determine the relevance of training areas and possible areas of employment for graduates. The formalized model is used in the software implementation of the job clustering module based on the obtained sets of key skills within the framework of a comprehensive toolkit for remote career guidance.

    Keywords: vacancies, demand for training areas, career guidance, digitalization of career guidance, formalized model, clustering, professions, key skills

  • Investigation of the influence of wind on the flight path in a Simulink model of a lightweight aircraft

    A Simulink model of a lightweight aircraft is being studied as part of the Aerospace Blockset package, including a system model of the aircraft, an environmental model, a model of pilot influences, and a visualization block. The structure of the flight model is considered and models of the effects of the environment and wind are disclosed in detail, consisting of blocks of physical terrain features, wind models and an atmospheric model, a gravity model, each of which is set to an altitude. The Wind Shear Model block calculates the amount of wind shear as a function of altitude and measured speed wind. The Discrete Wind Gust Model block determines the resulting wind speed as a function of the distance traveled, the amplitude and length of the gust. The turbulence equations comply with the MIL-F-8785C specification, which describes turbulence as a random process determined by velocity spectra. Simulation results are presented that reflect changes in the trajectory of movement under various wind influences specified in the wind speed gradient block.

    Keywords: modeling, airplane flight, Simulink, Aerospace Blockset, crosswind, turbulence, turbulence equations, gravity model, motion trajectory

  • The methodology of full-scale testing of reinforced concrete beams as part of a ribbed monolithic floor

    In accordance with the requirements of Federal Law No. 384-FZ, the safety and reliability of buildings and structures must be ensured. One of the ways to confirm the safety and reliability of building structures is to conduct field tests. The authors of this article have developed a method for full-scale testing of a reinforced concrete beam with a span of 14.52 m as part of a monolithic reinforced concrete ribbed floor. The procedure for testing the beam was drawn up with the development of measures to ensure safety during work, the adjustment of the beam testing method by loading was performed, the beam was tested by loading method with fixation of its deflections, followed by analysis of the test results. The test results showed that the developed method can be used as a full-scale test to confirm the safety and reliability of building structures, namely horizontal reinforced concrete structures.

    Keywords: building structures, beam, destruction, safety, methodology, technical condition, field tests

  • Basics of calculating a quantitative assessment of the installation manufacturability of steel structures with a span of up to 18 m

    The relevance of the issue of variant design is considered, taking into account the analysis of previously applied solutions. The concept of installation manufacturability of objects is revealed, its component properties are substantiated. A table of the hierarchy of installation manufacturability properties has been generated. The functions of each level of the property hierarchy are disclosed. The weight indicators of the criteria were calculated using an expert survey. a formula for a complex indicator of installation manufacturability was obtained. A hypothesis has been put forward about the quantitative assessment of the levels of installation manufacturability.

    Keywords: manufacturability, installation manufacturability, levels of hierarchy of installation manufacturability, weight of indicators of properties of installation manufacturability, installation of steel structures

  • Mathematical modeling of the motion of a planning body of complex configuration

    motion of the body are obtained, which can only be solved numerically. The equilibrium equations are solved and the basic stationary modes of body motion are obtained. The main result is the most gentle body planning mode. In the matlab computer mathematics system, a set of programs is written that searches for a numerical solution and outputs trajectories. The movement of the modes under consideration is modeled and the stability of the main modes is looked at using numerical calculations.

    Keywords: body, planning mode, stability, geometric dimensions

  • Development of a data indexing system for the production, economic and labor sectors of the penitentiary system

    The development of business analytics, decision-making and resource planning systems is one of the most important components of almost any enterprise. In these matters, enterprises and production facilities of the penitentiary system are no exception. The paper examines the problem of the relationship between existing databases and statistical reporting forms of the production, economic and labor sectors of the penitentiary system. It has been established that indirectly interrelated parameters are quite difficult to compare due to different data recording systems, as well as approved statistical forms. One of the first steps in solving this problem could be the introduction of a generalized data indexing system. The paper discusses data indexing systems, the construction of their hierarchical structures, as well as the possibility of practical application using SQL. Examples of implementation using ORM technology and the Python language are considered.

    Keywords: databases, indexing, ORM, SQL, Python, manufacturing sector, economic indicators, penitentiary system

  • Development of a retiling microservice in the Python programming language

    In the modern world, it is increasingly necessary to process geographical information in a variety of forms. This paper discusses the concept of «tile», its purpose, features, as well as the process of retiling, which is a method of creating and updating tiles. This technology helps to increase the efficiency of modern cartographic services, reducing the loading time of maps. The main stages of the development of a microservice implementing the retiling logic are presented sequentially. The main data provider is the OpenStreetMap (OSM) open source project. The spatial data set is a core OSM product and contains up-to-date geographic data and information from around the world. The technology stack is based on the Python language, to which specialized modules for working with tiles are added, as well as a library for implementing a simple and high-quality API.

    Keywords: Python, tile, retiling, OpenStreetMap, microservice, Flask-RESTX, mercantile

  • Statical algorithms for identifying unique features from a person's handwritten signature

    One of the most reliable methods of identity verification are biometric authentication methods. There are two types of methods: static and dynamic. Static methods include fingerprint scanning, 3D facial recognition, vein patterns, retina scanning, etc. Dynamic methods include voice verification, keyboard handwriting and signature recognition. As of today, static methods have the lowest type I and II error rates, because their primary principle of operation is based on capturing a person's biometric characteristics, which do not change throughout their lifetime. Unfortunately, this advantage, which accounts for such low type I and II error rates, is also a drawback when implementing this method for widespread use among internet services. If biometric data is compromised, user can no longer safely use method everywhere. Dynamic biometric authentication methods are based on a person's behavioral characteristics, allowing user to control information entered for authentication. However, behavioral characteristics are more vulnerable to changes than static, resulting in significantly different type I and II errors. The aim of this work is to analyze one of the dynamic methods of biometric authentication, which can be used in most internal and external information systems as a tool for authorization or confirmation of user intentions. Biometric user authentication based on their handwritten signature relies on comparing unique biometric features that can be extracted from signature image. These unique features are divided into two categories: static and dynamic. Static features are extracted from signature image, based on characteristics such as point coordinates, total length, and width of the signature. Dynamic features are based on coordinate dependency of the signature points over time. More unique features are identified and more accurately each is weighted, the better type I and II error rates will be. This work focuses on algorithms that extract unique features from static characteristics of signature, as most signature peculiarities are identified from the dependencies of writing individual segments of the signature image.

    Keywords: static algorithms, metrics, signature length, scaling, signature angle

  • Dynamic algorithms for identifying unique features from a person's handwritten signature

    Currently, to access information contained in autonomous and external information systems, user must pass an authorization process using modern methods of identity verification, such as: password protection, protection based on one-time codes, electronic signature-based protection, etc. These methods as always have worked well and still continue to provide secure access, however, biometric authentication methods are more reliable when access to confidential information should be limited to a single user. Today, there are two types of biometric authentication methods: static and dynamic. Static methods based on a person's biological characteristics that remain with them throughout their life, while dynamic methods based on a person's behavioral characteristics. Static methods are considered some of the most accurate, because most biometric parameters do not change over a lifetime. However, this method should only be used if chance of data compromise is very low, because in the event of leak, user will not be able to continue using these types of methods anywhere else. Dynamic methods, due to their behavioral characteristics, do not have sufficiently satisfactory type I and II error rates, as they directly depend on user's psychological and physical state. However, unlike static methods, user can control the information that will serve as a secret key for authorization in the future, so in case of a leak, user can always change the contents of the key for current and future services. This work examines one of these dynamic methods of biometric authentication: verification by handwritten signature. This method is considered more attractive among its counterparts, as in case of successful type I and II error rates, it can be applied in most existing services as a tool for authentication and confirmation of user intentions when signing various types of documents. The article discusses the main algorithms for verifying handwritten signatures by identifying unique dynamic features, dependent on the temporal and coordinate values of the analyzed samples of handwritten signatures.

    Keywords: dynamic algorithms, feature extraction, signature writing time, proximity of point coordinate functions, Fourier transform

  • Development of a mathematical model and a software package for automating scientific research in the field of financial industry news analysis

    The article is devoted to the development of a mathematical model and a software package designed to automate scientific research in the field of financial industry news analysis. The authors propose an approach based on the use of graph theory methods to identify the most significant scientific hypotheses, the methods used, as well as the obtained qualitative and quantitative results of the scientific community in this field. The proposed model and software package make it possible to automate the process of scientific research, which contributes to a more effective analysis of it. The research results can be useful both for professional participants in financial markets and for the academic community, since the identification of the most cited and fundamental works serves as the starting point of any scientific work.

    Keywords: software package, modeling, graph theory, news streams, Russian stock market, stocks, citation graph

  • A website for debugging of robots artificial intelligence technologies

    The article presents the state of technology of websites for designing robots with artificial intelligence. The image of a modern technical site-book as a place for the development of artificial intelligence applications is considered, the possibility of executing algorithms from the page to ensure the connection of robots with real and virtual objects is shown.

    Keywords: mathematical network, technical website-book, artificial intelligence, algorithms executed on the website-book, network development of robots