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  • Method of recognition of plant diseases by textural signs using fuzzy logic

    A new method, including fuzzification operation, representing the calculation of the membership functions of the key parameters of the R, G, B, RG, RB, GB components of the original color RGB photographs of plant leaves and the GLCM adjacency matrix, the formation of fuzzy conclusions about the type of plant disease, defusing using threshold binarization signs and majority voting on 24 parameters.

    Keywords: GLCM - matrix, fuzzy logic, functions of accessories, binarization of key characteristics, majority voting

  • Locally - non-equilibrium heat transfer in а rod with forced convection

    Based on Dual-Phase-Lag theory a mathematical model of heat transfer in a rod was developed. During the derivation of the differential equation, the modified Fourier law was used. Analysis of the calculation results made it possible to determine the dependence of the optimal rod length on the intensity of heat transfer from its side surface.

    Keywords: heat transfer intensification, third kind boundary conditions, temporal nonlocality, Dual-Phase-Lag theory, finite-difference method

  • Synergetic synthesis of nonlinear regulators for the pneumatic actuator positioning problem

    The complexity of the organization of pneumatic actuator control makes a nonlinear mathematical apparatus that takes into account the thermodynamic processes in the filling and draining of the working cavities of the pneumatic cylinder. The review of existing approaches and methods of pneumatic systems control allows us to draw conclusions about a significant simplification of the mathematical model of the system under study, which leads to a discrepancy between the mathematical model of its technical original and the limited application of the developed control laws.

    Keywords: the pneumatic actuator nonlinear mathematical model, synthesis of a synergetic controller, invariant manifold

  • Software complex of simulation modeling of the influence of the main integrated indicators of the distributed information processing system on its reactivity

    This article describes a software complex simulation, which allows you to evaluate the impact of the main integrated indicators of the distributed information processing system on its reactivity, taking into account the properties of self-similarity of traffic, TCP/IP data transfer Protocol, and various architectures. The software package consists of software-implemented mathematical models of distributed information processing systems based on file-server, two-level client-server and three-level client-server architecture, as well as the algorithm of distributed information processing system objects distribution. The platform AnyLogic PLE was used as a software tool.

    Keywords: a distributed information processing system architecture "file-server", two-tier architecture "client-server", three-tier architecture "client-server", simulation, self-similar traffic, agent-based modeling, discrete event simulation, system dynamics

  • Methods of functional and logical modeling of associative memory devices and systems

    A methodology for the study of associative memory devices and systems in the environment of functional-logical modeling MatLab / Simulink and the development tools of programmable logic integrated circuits is proposed. To this end, it is proposed to implement the typing of the representation and modeling of such devices and systems by implementing the characteristics of the representation and organization of network associative structures in the modeling environment.

    Keywords: Associative memory devices and systems, functional and logical modeling

  • Mathematical model of the formation of cavitation bubbles in a centrifugal pump

    The process of cavitation is one of the reasons for the premature wear of pumping equipment components. Elements of a pumping wheel are subject to the greatest wear. In addition, cavitation causes undesirable effects such as vibration and noise. In order to reduce cavitational damage and increase the service life of pumping equipment, the authors of this article propose to install a special-shaped flow divider at the pump inlet that breaks the flow entering the pump into separate jets of a certain shape and structure.

    Keywords: fluid, centrifugal pump, regulation, cavitation, flow, bubble, flow divider

  • Fast Matlab-based Finite Element Solver for the Problem of Bending of Mindlin Plates

    In this paper we describe efficient Matlab-based implementation of the finite element solver for the problem of bending of Mindlin plates. This solver is tested on fine meshes consisting of a large number of linear rectangular finite elements. The performance of this solver is so good that even for fine meshes considered the CPU time is small enough.

    Keywords: simply-supported plate, Mindlin plate theory, sparse solver, Matlab, finite element method

  • Dynamic characteristics of the relative humidity sensor

    The article considers the solution of the problem of determining the dynamic characteristics of the relative humidity sensor, the mathematical model of which was based on the first order aperiodic link. The solution algorithm consists in minimizing the value of the standard mismatch of the approximating function and the set of experimental data. The results of processing experiments with the DHT-22 temperature and humidity sensor are presented. The sensor was placed three times in a medium with high humidity, which allowed to obtain an average experimental transient response. The period of measurement and registration of humidity and temperature was 1.5 seconds. The proposed method of calculating the dynamic parameters of the sensor allowed to determine the value of the time constant and the gain of the aperiodic link for the sensor under study. The obtained dynamic characteristics can be used to form an inverse transfer function for the humidity sensor.

    Keywords: capacitive humidity sensor transient response, the sequence of measurements, the time constant, the minimization of the error

  • Software for multivariate analysis of variance

    The object of research in this article has become a rather important topic of describing such a statistical method as analysis of variance. The fact is that many software products consider, basically, a case when the number of factors is not more than two. With the exception of such a powerful product as a SPSS Statistica. The same can be attributed to scientific works, where the method of analysis of variance with a large number of factors is very rarely considered and described (often, when it comes to multifactorial analysis of variance, two factors are also considered). Therefore, an analysis was made of the existing mathematical apparatus, a proprietary idea was proposed for the implementation of this statistical method, and was created a software product to demonstrate how its work.

    Keywords: variance analysis, general case, software implementation

  • Simulation of the pasteurization process using system analysis methods using functional risk analysis

    The article is devoted to the study of the possibility of applying the methods of system analysis in modeling the process of pasteurization of milk. The paper discusses structural-parametric, functional-operator, informational and target management models for a convenient "description" of the pasteurization process. The resulting models and their coefficients describing the process of pasteurization, based on the methods of system analysis, are suitable for the practical solution of the problem of managing the production process. The authors applied functional risk analysis and identified the risks of milk pasteurization.

    Keywords: system analysis, pasteurization, milk, risk, modeling, process, functional risk analysis, system analysis, model, production

  • Simulating wind loads on unique buildings in SolidWorks

    During designing unique buildings, great attention is paid to the correct setting of operational loads. When determining the wind load for particularly difficult cases, it is proposed to blow models of objects in a wind tunnel. In the case of using virtual models, the main tool is the ANSYS complex. This complex belongs to the "heavy" scientific programs, therefore, for building structures, the SolidWorks software package can be convenient. The article describes the simulation of variable height wind impact on a unique building in this program. The loading of a three-dimensional model of a high-rise building with cantilevered floors was carried out and the law of distribution of static pressure on a complex object was established by blowing the model in a virtual wind tunnel. In this case, the modeling process itself is simpler and more convenient than in ANSYS.

    Keywords: Unique building, wind load, wind tunnel, building frame, finite element method. pressure console floor

  • Determination dominating set intuitionistic fuzzy graph

    In this paper, the concept of minimal intuitionistic dominating vertex subset of intuitionistic fuzzy graph was considered, and on its basis the notion of a domination set as an invariant of the intuitionistic fuzzy graph was considered. A method and an algorithm for finding all minimal intuitionistic dominating vertex subset and domination set were proposed. This method is the generalization of Maghout’s method for fuzzy graphs. The example of finding the domination set of the intuitionistic fuzzy graph was considered as well. The considered method and algorithm can be used to find other invariants, in particular, externally stable set, intuitionistic base and antibase of the intuitionistic fuzzy graphs.

    Keywords: intuitionistic fuzzy set, degree of belonging, degree of non-belonging, fuzzy relation, intuitionistic fuzzy graph, intuitionistic fuzzy graph of the first kind, domination set, algorithm, disjunctive member, adjacency matrix

  • Model for estimating the complexity of physical schema for relational database

    In work area of application for quantitative metrics of databases are considered. Quality control of the database scheme is impossible without numerical indicators. Metrics of the database can be calculated it is automated that guarantees the accuracy and recurrence of such measurements. In article the model for assessment of complexity of the physical scheme for relational database based on metrics of the table of the database is offered. For the offered model by using the method of T. Saati, received coefficients which consider extent of influence of each metrics on complexity of the database. On the example of real projects for databases quantitative measurements of their metrics in MySQL are executed. The comparative analysis of the results obtained for the model of complexity estimates for various projects of physical schemes for databases and the amount of information contained in sql-scripts of these databases are described.

    Keywords: evaluation of complexity, database, physical schema, model, SQL, entropy

  • Application of simulation models to the IC parameters testing of pulse voltage converters

    The paper reveals data on the development of simulation models of integrated circuit pulse voltage converters for applying in automated measuring equipment used in the tests of integrated circuits. The integrated circuit of switching voltage converter LM2676 was simulated taking into account heat generation and taking into account the mutual influence of crystal temperature on external electrical characteristics as part of a general behavioral model.The authors obtained results and dependences, coinciding with the experimental data and with the SPICE model at the transistor level, that reflects the influence of the crystal temperature on the the chip operation. In addition, the authors consider a possibility of using behavioral models as a source of reference information in the process of testing electronic components.

    Keywords: ATE, integrated circuit (IC) testing, switching voltage converters, behavioral model, VHDL-AMS

  • Domain modeling to support the operation of technical systems

    The article discusses an integrated approach based on the use of expert knowledge to develop a conceptual domain model in terms of monitoring the required operational reliability of technical systems. The need to formalize the key task of logistics analysis is necessary to provide support for the operation of equipment and the creation of an integrated logistics system.

    Keywords: integrated logistic support, life cycle, functional failure, operational reliability, severity of consequences

  • Modern Internet security threats and countermeasures (review)

    Over the past decades, the Internet has changed our lives and ways of doing our daily activities. The Internet has changed the methods of communication, and for many enterprises and organizations the technology has changed. In today's business environment, if an organization does not have any presence on the Internet, it risks remaining behind its competitors, as the Internet and technology continues to develop and develop us. This paper provides a small review of the literature on Internet security threats. Typical threats are classified and their effects are shown. Methodical recommendations for their minimization are given.

    Keywords: computer security, security threats, spoofing, denial of service, DoS, DDoS, cyber security

  • The method of improving the quality of single-image video sequences

    The article discusses the causes of the emergence of digital noise in video sequence images. It is proposed to evaluate the effectiveness of noise suppression methods by measuring the peak signal-to-noise ratio. A method is proposed for preliminary improvement of the quality of images in a video sequence for further processing in order to search and recognize objects on a complex background. The originality of the method consists in using the analysis of the contribution coefficient of single images in a video sequence. The results of experiments with images from the USC-SIPI database are presented. The results obtained are not inferior to their counterparts, and surpass them in some indicators.

    Keywords: video sequence processing, video enhancement, object recognition on a complex background

  • Neural Network Application Methods Used to Evaluate and Increase Photorealism of Virtual Reality

    The article focuses on the possibility of using neural networks to increase the level of the graphic component of virtual reality. An image quality evaluation method using three criteria is examined: photorealism of image macrostructure, photorealism of image microstructure, as well as the level of its distortion. Its implementation relies on the VGG neural network, trained in a variety of images, evaluated by the presented criteria. After metric realization is complete, a method is proposed that has to do with automatic selection of parameters and contents of the virtual scene with metric maximization in the images obtained from different angles. Next, a method is considered and evaluated, where rendering algorithm is replaced by a neural network. At which point, methods to improve the quality of the final image are suggested. Based on the results of the experiments, Wasserstein generative adversarial networks (WGAN), distinguished by the highest level of image quality, are singled out. Further on an option is proposed to improve this approach in terms of speed and quality of the result that consists of breaking up one large network into an ensemble of smaller ones. It should be emphasized that each network of the ensemble processes only part of the image relating to one type of segment. Next, it is prudent to consider the possibility of applying this algorithm in real time, to which end optimization of neural networks is conducted to the detriment of quality, but with a significant increase in execution speed.

    Keywords: Image quality enhancement, image quality evaluation metrics, neural networks, virtual reality, synthetic data, GAN, WGAN, photorealistic synthetic images

  • Elaboration of methods for determining wind loads for objects of parametric architecture

    The article considers the modeling of wind impact on the objects of parametric architecture. To determine the optimal shape of the surface, the evolution of the analytical surface shaping, formed by congruent curves in parallel planes, obtained by the rotation of the reulault triangle with a plane perpendicular to the axis of rotation, is studied. Based on the results of a numerical experiment using the finite element method, the rational analytical surface of the object of parametric architecture, resistant to wind, is determined. The dynamic characteristics of the object of parametric architecture are obtained. Recommendations are given to clarify the methods of determining the wind load for buildings and structures of complex geometric shape.

    Keywords: parametric architecture; wind load; modal analysis; pulsation component; building frame; finite element method

  • Method finite elements thin-walled profile shelves surround the nishing

    Discusses the research in the field of design of frame structures, the cross-trusses of thin-walled beams , preliminary finite element analysis of a thin-walled profile model with shelves of a bulk shaped element. Achievement in the analysis model, the corresponding test purposes.Determination of measurement error and results obtained in the calculation.Adjustment of the model.In this work, according to the results of the calculation, the mounting points of the strain gauge are taken close to the shaped element. Restrictions of displacements were introduced into the computational model for leveling the difference between the calculations and the experimental results. The results of the study profiles.

    Keywords: method finite elements, thin-walled profile, core structures

  • Application of BIM in evaluation of property and project of EBIM

    Technical progress makes humanity create new technologies and methods in all spheres of life. Evaluation of property also in there. In current moment there are several methods, which are badly obsolete. For example, there are some cases, when building in decrepit or emergency condition were able to buy in cost several times higher than objective cost. These cases aren't unique. New method of evaluation of property could possibly help if not to stop in all appearing of this cases but less their amount. New method is based on Building Information Model (BIM). This model allow take all needed information about building in the currnet moment of time and see in dynamic, how change different indicators of building. This system can be more useful if it associates some amount of building, which differs indicators of interest building and reflecting effects of that building on themselves. This technology can be looked as Extented BIM. Consideration of implementing BIM in evaluation of property has very perspective vay - this can accelerate the time building can be evaluated, and also it let potential client to see all information about building which he need. This makes process of purchase-sale of property more clear, which, by turn, help avoid conflicts when property being researched before purchasing.

    Keywords: Building information model, Building, Evaluation of property, property, BIM, BIM-Technologies, Extented BIM, Using BIM, BIM-Modeling, BIM functions, BIM destination, BIM-model of building

  • The selection of structural and insulation concrete based on granulated foam glass with the use of mathematical planning of the experiment

    The factors that must be taken in the selection of lightweight concrete composition with the use of granulated foam glass (GFG-concrete). In addition, the effect of the composition of concrete mixture on the physical, mechanical and thermal properties of the obtained material is shown. Portland cement CEM II / A-S-32,5 B, produced by PAO «Gornozavodskcement», was used as a binder when selecting the composition of GFG-concrete; quartz sand of the Zaostrovsky opencast mine of Perm with a particle size module of 1.96 was used as fine aggregate; granulated foam glass of fractional composition of 5-10 and 10-20 mm was used as a coarse aggregate. Determination of physical, mechanical and thermal properties of GFG-concrete was carried out according to standard methods. The obtained mathematical models allowed us to establish a functional relationship between technological factors of variation (content of granulated foam glass and water-cement ratio) and output optimization parameters (average density and compressive strength). The highest compressive strength (9,0-10,93 MPa) of HPS-concrete was obtained with a content of coarse aggregate of 20-40% and a water-cement ratio of 0,4-0,6. The average density does not exceed 1500 kg / m3, and thermal conductivity varies from 0,207 to 0,375 W/m⸱K. The optimal composition is the content of GFG from 20 to 40% and water-cement ratio of 0,4-0,6. Research have also shown that by changing technological factors, it is possible to obtain GFG-concrete with a density class D500-D1500.

    Keywords: water-cement ratio, granulated foam glass, lightweight concrete, mathematical experiment planning, response surface, compressive strength, average density, regression equation

  • System perception and transfer of images printing symbols with the original in the matrix of the memorable device of the personal computer, defining types of symbols

    The authors have developed a device consisting of a system of perception of images of printed characters and a personal computer (PC), which determines the types of characters. According to the program developed by the authors, the PC contours the image of the printed symbol in a rectangular matrix consisting of the cells of the PC's storage device. As a result of the edging of the shape of the printed symbol, essential and necessary signs were determined - the directions of the elements of the shape of the symbol, according to which, using the developed algorithm, the PC determined the type of this symbol relative to others. The perception system includes a small-sized television tube - a vidicon with a generator of sweeps of a vidicon beam on its screen vertically and horizontally, two channels and a coincidence circuit. The developed system of perception is distinguished by: simplicity of design, compactness, efficiency.

    Keywords: direction, perception system, trigger, amplifier, pulse counter, coincidence circuit

  • Analytical and numerical simulation of the operation of distributed information systems with self-similar input traffic

    This article formulates the main stages of the process of constructing analytic-numerical models of functioning of distributed information systems with non-exponential (self-similar) input traffic of requests. Each separate stage of modeling, at the conceptual level, is reduced to solving a certain class of mathematical problems. The basis of the mathematical apparatus for obtaining the basic integral characteristics of the quality of distributed information systems functioning lies in the method of analyzing the average values ​​of networks of queues. The basic relationships for calculating the reactivity of distributed information systems operation are given.

    Keywords: distributed information system, discrete self-similar process, Hurst parameter, Pareto distribution, queuing network, Kendall classification, Polacek-Khinchin formula, average system response time

  • Estimation of the mathematical expectation of the insulation resource in problems of increasing the reliability of electrical equipment

    The model of the occurrence of failures as a result of aging of insulation materials of power cable lines is considered. It is shown that the residual life depends on the ratio of the safety margin and the ultimate strength of the materials used. A simulation of the resource actuation processes was carried out using a mathematical model of the insulation state that relates the time and probability of its trouble-free operation with certain parameters of it. The model allows to predict the state of the insulation and the service life of the power cable lines.

    Keywords: Reliability, life, insulation materials, heat aging