VESTNIK OF ASTRAKHAN STATE TECHNICAL UNIVERSITY SERIES MANAGEMENT COMPUTER SCIENCE AND INFORMATICS
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Published By Astrakhan State Technical University

2072-9502

Author(s):  
Natalia Fedorova

The article highlights the different aspects of complex technical systems that can be ordered and classified in accordance with the totality, structure and values of the attributes characterizing these systems by a unified approach to various types of classifications. The most complex classifiers studied in this work are hierarchical-matrix, cyclic and zonal classifiers. Zones are the areas identified in the space of classification attributes that characterized by a similar value of an additional target classification attribute. The dimension of the zonal classification is equal to the number of descriptive classification attributes, the zonal dimension is equal to the number of zones. Adding the zones is carried out according to the target classification criterion, multiplying the zones consists in introducing the new descriptive classification attributes. Cyclicity is repetition of the similar elements that occurs in the space of physical quantities or other parameters. The concept of cycle stages is defined for all cycles, which is a specific (target) classification attribute. The internal dimension of the cycle is equal to the number of stages, the external dimension is equal to the number of acts of the cycle, the descriptive dimension is equal to the number of descriptive classification attributes. Addition of cycles can be carried out both by stages and by descriptive features and consists in increasing the number of values of classification attribute. Multiplication of cycles consists in the introduction of new descriptive classification attributes. Zonal and cyclic classifiers are widely used in the practice of describing and planning technical energy systems. A wide range of classifiers ordered from the standpoint of a unified formal theory of classification will take into account the features of specific technical systems, the conditions for the objects functioning, the context of the interpretation area. As a re-sult, the degree of adequacy of classifiers to the diversity of the interpretation area objects and the representativeness of models based on classifiers will increase


Author(s):  
Ivan Vladimirovich Chicherin ◽  
Boris Andreevich Fedosenkov

The article defines the object of control in the form of signals of current trajectories (CT), along which unmanned vehicles (UMV) move. It describes the subject field of research – the principle and technology of forming the signals generated by the computer-aided system for modal controlling the UMVs during their movement along quarry routes. In order to develop procedures for identifying an upcoming trajectory of the UMV when bypassing some static or dynamic obsta-cles, conditions are included in the software and hardware complex for the formation of the UMV corresponding trajectory direction based on assigned sinusoidal-like frequency-time-dependent functions (chirp signals) responsible for redirecting the UMV along a particular trajectory. The cor-responding chirp signals for the left and right deviation trajectories of the UMV are fixed. The no-tion of sporadic disturbances and force-modal transient processes (TP) is introduced. There has been also reviewed a new description of TP, whose signal contains the variable frequency changing by a certain law depending on the direction and nature of a CT deviation and the environment of UMV. The essence and reasons for the effects of structural and parametric nonstationarity of the control object (CO) are explained. Analytical and graphical interpretations of the emerging non-stationarity caused by the introduction of additional stationary and dynamic-type poles into the CO are presented. It is noted that the stationary poles characterize the inertia of the aperiodic components of the trajectory chirp signals, and the dynamic ones determine the permanently varied frequency of transients (their chirp form). The properties of both sporadic and forced-modal TPs’ poles localized on the complex plane are characterized. Calibration characteristics are determined that establish a relationship between the instantaneous frequency of TP and the metric deviation of UMV CT relative to the nominal axial trajectory. The difference between the procedures of localization and re-localization of poles for modal upward and downward reverse TP, on which the efficiency and safety of UMV moving along the quarry routes, depends, is functionally identified and considered. All the procedures mentioned above make it possible to monitor online and control effectively the dynamics of operative and safe UMV trajectory moving along technological quarry routes in open pit mining


Author(s):  
Svetlana Abdulaevna Feylamazova ◽  
Zukhra Khalipaevna Akhmedova ◽  
Zinfirat Shagumilaevna Abdurazakova

The development of Internet technologies allows remote control of various devices. The paper presents a description of a greenhouse microclimate control device with remote control. There are used the concept of the Internet of Things, which allows to remotely control devices using cloud services. The Internet of Things is one of the popular trends in the networking environment allowing data to be transferred between devices. There is no need to write a program to transfer data, it is enough to use one of the many existing cloud services. The cloud service records the microclimate parameters and displays them on-line on the user's computer or phone. The user can observe the data received from the sensors installed in the greenhouse and control the executive devices, namely, turn on and off the heating, irrigation, lighting and opening of the vents. The device under development will help not only take the microclimate indicators in the room and transfer them via the Internet to a personal computer or telephone while being remote from the measurement object, but also control the actuators inside the greenhouse. The functional requirements for the developed device are determined, the block diagram of the device is shown, the main element of which is the Arduino Uno board, on which not only the microcontroller is located, but also the connectors of external devices. The user interface is presented and described, which provides interaction between a user and a control object, developed in the IoControl cloud service, and the stages of its development are also presented. The modes of microclimate control and the corresponding actuators and variables are considered.


Author(s):  
Nadezhda Kaznacheeva ◽  
Aleksey Poletaykin ◽  
Lyubov' Danilova Filippovna ◽  
Sergey Gennadievich Sinitsa

The article focuses on building an individual educational trajectory of a university student. This concept is formalized in the form of a hybrid mathematical model. This model is based on a structural model of educational competence. In this case, the competence is a basic construct of the educational program, it acts as a prototype of the structural model of individualized educational content. The main source of semantic and control information is the digital twin sys-tem. The digital double of the educational program formalizes its structure and content in strict ac-cordance with the regulatory requirements of federal state educational standards. The digital twin of a student fixes and processes his digital tracks throughout his life. The digital twin of the labor market formalizes the structure of a certain segment of the labor market in the context of the re-quirements for professional and personal qualities of specialists. There has been substantiated the need for proactive management of restructuring and rebranding the professional educational pro-grams in accordance with the changes at the labor market. A significant contribution to the man-agement of these evolutionary processes is made by the dynamics of a student’s activity, which is reflected in his digital traces. Hybridization of these digital twins into the system of constructing individual educational trajectory allows the semantic marking and weighing of the educational situation and projected content. Based on a suspended educational content and taking into account the regulatory requirements of educational standards and additional requirements of the educational organization, optimization modeling of an individual educational trajectory in its structural and meaningful context is carried out. The study of the structural features of the constructed hybrid mathematical model made it possible to determine and substantiate its rational structure.


Author(s):  
Viktor Afonin ◽  
Anastasia Vasilevna Savkina ◽  
Vladimir Nikulin

The article presents an algorithm and a methodology of ranking a group of raster images by using the criterion of their expected quality. Ranking refers to the evaluation of a sample of bitmap images in a descending order of their quality, the image quality assessment being performed on the basis of a number of statistical parameters, such as coefficients of variation, determination, rank correlation index, as well as errors (absolute maximum error, average error, average quadratic error). The differences between the images are based on converting a full-color RGB image into HSV, Lab, NTSC, XYZ, YCbCr color models, which are represented as one-dimensional pixel ma-trices. The colour model RGB is taken as a reference. In relation to it, the proposed statistical char-acteristics of other color models are compared, any object of each color model being compared with the base model - an RGB image. Based on this comparison, all images of a given group are analyzed independently of each other. Image quality assessment is performed in a module that can be used to cycle through multiple images and is represented in numerical form as a real number. One of the module blocks calculates the statistical parameters between each color model and the base RGB model. After receiving the values of the quality scores they are ranked according to their values. As a result, an image with a higher or lower scene quality can be determined. Images with blocking artifacts, noisy images of the salt & pepper type, and images with strobe effects artifacts were considered as test images.


Author(s):  
Andrej Vladimirovich Averchenkov ◽  
Amirmamad Murodmamadovich Alidodov

The article is focused on the description of the system of control over the social system of foreign students studying in the Russian Federation, which is based on the approaches and methods of control theory. The proposed model of the control system assumes developing the control influence, specification of the output coordinates of the controlled object, including after working out the controlling influence, description of the external environment. There is presented a visual model of the social system control system of Tajik students studying in the RF higher educational institutions and its formalization from the standpoint of a set-theoretic approach. There are described the principles of control by mistake and omission, which allows adjusting the control im-pact on the social system of the foreign students studying in the Russian Federation in order to achieve the targets of the national system of higher education. Managerial decision-making in the field of managing the social system of the foreign students studying in the Russian Federation is based on a process approach. There is proposed a set-theoretic model of control system of foreign students studying in the Russian Federation as a basis for further formalization of the task of con-trol, setting criteria for optimality and corresponding restrictions in the similar social systems. The context diagram of the management process of the developed social system of foreign citizens studying in higher education institutions of the Russian Federation is presented in the IDEF0 nota-tion, which made it possible to concretize the features of the process of its management. The pro-spects for further development of control processes in the analyzed social system are associated with the formalization of the control task. The directions of further scientific groundwork for repli-cating the grounds of the control theory to related organizational systems are determined.


Author(s):  
Sergey Amelin ◽  
Marina Arkad'evna Amelina ◽  
Sergey Vladimirovich Drozdetsky ◽  
Igor Vladimirovich Yakimenko

The article considers the problems of analyzing DC-DC voltage converters and analyzes the advantages, disadvantages, as well as the scope of full switched and averaged continuous models of the converters. The feasibility of using the complex of two models (full switch model and averaged continuous model) for analyzing their operation is proved. The general approach to the construction of continuous models of DC-DC voltage converters based on state-space averaging method is considered. Disadvantages of the averaged models using a classic approach are shown. The relevance of the development of universal continuous models of DC-DC converters is substantiated. The possibility of creating such models using averaged models of PWM switching structure included in the DC-DC voltage converter is shown. Analyzed the typical structure of the switch-mode power supply with feedback. An averaged model of the switching structure is proposed, basing on which continuous models of DC-DC converters with any topology can be built. The processes occurring in this switching structure in the mode of continuous and discontinuous choke current are analyzed. A method for constructing continuous models of the main types of DC-DC voltage converters based on switching structure averaged model is proposed. The adequacy of continuous models obtained by this method has been proven. The results of modeling transients on the continuous and full switch models for inverting voltage regulator are demonstrated. The possibility of accounting in the model of active resistances of switches and cumulative choke is shown. The possibility of using the proposed model to obtain the open loop transfer functions is demonstrated, in particular, the characteristics of the duty factor - output voltage. These transfer functions can be used to synthesize control system compensating circuits of the switch-mode power supply. The possibility of using a single generalized averaged model of the switching structure to build continuous models of converters with complex topology using both the Voltage Mode and Current Mode is shown. This creates prerequisites for developing a universal averaged continuous model for DC-DC converter based on this principle


Author(s):  
Rodmonga Kondratyevna Potapova ◽  
Andrey Vladimirovich Dzhunkovskiy

The paper gives analysis of feasibility of using linguistic steganographic trigger-containers as means of linguistic-based text watermarking. The proposed approah is based on the previous experimental research in the context of Russian native speaker text juncture perception. It was posited that specific minimal text modifications addressed in the paper may be used as means of text watermarking with the aim of tracking the leak of information for the purposes of taking legal actions, enforcing non-disclosure agreements, and testing for internal vulnerabilities. There is analyzed the viability of altering paragraph juncture points in Russian texts and, through the use of the corresponding trigger-containers, usage of this alteration as a means of linguistic watermarking.


Author(s):  
Elena Georgievna Krushel ◽  
Ekaterina Sergeevna Potafeeva ◽  
Tatyana Petrovna Ogar ◽  
Ilya Viktorovich Stepanchenko ◽  
Ivan Mikhailovich Kharitonov

The article considers a method of reducing the time spent on the experimental study of the frequency properties of an object with an unknown mathematical model by using the cyber-physical approach to the automation of the experiment. Nonparametric estimates of unknown frequency characteristics of an object are received from experimental data on the reaction of the object's output to the input harmonic signal in the form of a mixture of sinusoidal signals of different frequencies. To divide the output signal into components corresponding to each frequency, a computer technology is used that implements an optimization procedure for finding the values of both real and imaginary frequency characteristics, according to the frequencies represented in the harmonic input signal. The method is also suitable for accelerated evaluation of the frequency characteristics of an object with an unknown delay. There are considered the aspects of frequency properties estimation in the problem of closed system stability analysis, which is supposed to control an object with incomplete information about its model using a series-connected proportional-integral controller. The results of quick estimating the frequency characteristics of the object are used to identify the parameters of its transfer function. To solve the parameterization problem, there are used automation tools for calculating the transfer function according to data on the points of frequency characteristics implemented as part of the open-access computer mathematics system Scilab. There is given an example illustrating the possibilities of developing a control system using a reduced-order object model, as one of the applications of the results of parametric identification of the transfer function


Author(s):  
Andrej Vyacheslavovich Mikheev

The article considers a probabilistic method for determining production functions. The method consists in finding the expected value of the function that determines the economic and mathematical principle of production. It is assumed that the factors of production and/or their specific values included in this function are random variables. It is shown that depending on the principle of production such averaging gives different probabilistic classes of production functions. Functions that are elements of the same class differ from each other in the probability distribution of the relations of production factors to their specific values. Two probabilistic classes of produc-tion functions are constructed. The first class is generated by the Leontief production principle, the second – by generalization of this principle for the case of partially or completely fungible factors of production. There are established the laws of probability distribution and the conditions, under which the linear combination of the AK-model and the Cobb-Douglas production function, as well as the CES production function, are elements of the class of Leontief production functions. It is shown that the linear production function belongs to the class of generalized Leontief production functions. The probability density functions of the products number for these two classes of pro-duction functions are found.


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