Кафедра "Інтернет речей"

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/5398

Увага! Поповнення колекції кафедри "Інтернет речей" – призупинено.

Від вересня 2022 року кафедри "Інтернет речей" та "Мультимедійних інформаційних технологій і систем" об’єднані у кафедру "Мультимедійні та інтернет технології і системи".

Первісна назва кафедри – "Розподілені інформаційні системи і хмарні технології".

Переглянути

Результати пошуку

Зараз показуємо 1 - 9 з 9

Analysis of the input material flow of the transport conveyor
(Національний гірничий університет, 2023) Pihnastyi, O. M.; Sobol, Maksym
Purpose. To develop a method for analyzing the material flw entering the input of a conveyor section, based on the decomposition of the input material flw into a deterministic material flw and a stochastic material flw. Methodology. The analysis of experimental data characterizing the input material flw was performed using the methods of the canonical Fourier representation of a random process. Findings. A method for representing a stochastic material flw as a combination of a deterministic process and a stationary random process with ergodic properties is proposed. Originality. The originality of the obtained results lies in the fact that, for the fist time, a method of analysis based on the decomposition of the input material flw for a conveyor section has been proposed, which, unlike the existing methods of input flw typing for the mining industry, will allow us to independently perform deterministic flw typing and stochastic material flw typing in transport conveyors. The proposed approach makes it possible to highlight special characteristics separately for deterministic and stochastic material flws. This will make it possible to use the obtained regularities to increase the accuracy of the conveyor model and will accordingly increase the quality of the belt speed control systems and the flw of material coming from the input bunker. The obtained results are of particular importance due to the fact that the characteristics of the deterministic material flw are directly related to the technical or technological factors of material extraction. Practical value. The obtained results allow determining statistically stable regularities for the incoming flw, which makes it possible, based on these regularities from the set of available control algorithms, to choose the optimal control algorithm for the parameters of the operating conveyor section. This allows reducing the enterprise’s energy costs of the transportation of material. The proposed method can be successfully applied to build random number generators simulating the sequence of values of the input flw of material. The developed generators can be used both for validating existing belt speed control systems and creating new control systems based on neural networks. This opens perspectives for the design of effctive systems for controlling the flw parameters of transport system, based on the transport conveyor model, which takes into account the stochastic nature of the incoming material flw.
The Input Material Flow Model of the Transport Conveyor
(Institute of Electrical and Electronics Engineers, Inc., 2022) Pihnastyi, O. M.; Sobol, Maksym
This paper discusses the problem of forming a data set for training a neural network used to build a model of a multi-section conveyor. The analysis of the models, which are used by designing the flow parameters control system of the transport system, is given. The conditions of applying a neural network in the transport conveyer model are justified and determined. Methods for generating a data set for training a neural network are discussed. As the main approach, the use of production data obtained from functioning transport conveyors is considered. Statistically processed data can be used to build generators of stochastic processes that model the incoming material flow for the transport system. The development of these generators to form the input flow of the material of the transport system opens up the possibility of analyzing and monitoring conveyor models in various modes of its configuration. A statistical analysis of the incoming material flow of the transport system was carried out and its number characteristics were determined. The correlation function characterizing the input flow of material for the transport system is considered. The introduction of dimensionless parameters to describe the input material flow made it possible to scale the results of work for a wide class of conveyor-type transport systems.
Analysis of a Dataset for Modeling a Transport Conveyor
(2022) Pihnastyi, O. M.; Burduk, Anna
The analysis of the works, which considered the use of neural networks for modeling a multi-section transport conveyor, was carried out. The prospects for the use of neural networks for the design of highly efficient control systems for the flow parameters of a multi-section transport conveyor are studied. The problem that limits the use of neural networks for building control systems for the flow parameters of a multi-section transport conveyor is considered. The possibility of constructing generators for generating a data set for the process of training a neural network is being studied. A method for generating a data set based on experimentally obtained measurements of the instantaneous values of the input material flow as a result of the operation of industrial transport systems is proposed. Using dimensionless variables, a statistical analysis of a stochastic flow of material entering the input of the transport system was performed. An estimate of the correlation time of a stochastic process characterizing the input flow of material is given. The recommendations on choosing the type of correlation function for the model of the input material flow were confirmed. It is demonstrated that the input flow of material is a non-stationary stochastic process. Approximations for modeling the input flow of materials of the operating transport system are considered.
On the Characteristics of the Input Material Flow of the Transport Conveyor
(Vasyl Stefanyk Precarpathian National University, 2022) Pihnastyi, O. M.; Sobol, Maksym; Yelchaninov, D. B.
In this paper, the statistical characteristics of the flow of material entering the input of a conveyor-type transport system are studied. For a set of data obtained as a result of experimental measurements of the input flow of material, the law of distribution of a random variable and the correlation function is investigated. Theoretical assumptions about the law of change of the correlation function for the input flow of material are confirmed.
Об использование асимптотического приближения модели максвелл элемент для анализа напряжений в конвейерной ленте
(2022) Пигнастый, Олег Михайлович; Чернявская, Светлана Николаевна
Рассмотрены особенности распространения динамических напряжений в конвейерной ленте, свойства материала которой соответствуют модели Maxwell element. Приведен обзор публикаций с использованием моделей вязкоупругого элемента для описании процесса распространения динамических напряжений в конвейерной ленте. Представлены аналитические выражения для расчета динамического модуля упругости, модуля потерь и угла механических потери в зависимости от частоты продольных колебания в ленте протяженного транспортного конвейера. Для анализа процесса распространения динамических напряжений введены безразмерные параметры, характеризующие специфические особенности протекания вязко-упругого процесса в конвейерной ленте, свойства материала которой соответствуют модели Maxwell element. Выполнен переход к безразмерной модели Maxwell element и произведен анализ взаимосвязей между напряжением и деформацией элемента конвейерной ленты для предельно больших и малых значений безразмерных параметров. Дано обоснование области применения модели Maxwell element. Показано, что при достаточно высоких частотах продольных колебаний в конвейерной ленте взаимосвязь между напряжением и деформацией элемента конвейерной ленты соответствует закону Гука. Проведен качественный анализ продолжительности времени релаксации для материала конвейерной ленты, свойства которого соответствуют модели Maxwell element. Выполнен анализ распространения динамических напряжений в конвейерной ленте для характерных режимов функционирования транспортного конвейера. Исследованы переходные режимы функционирования конвейера, при которых к элементу ленты внезапно приложена постоянная по величине или мгновенная нагрузка. Определены и проанализированы условия, при которых модель Maxwell element может быть заменена моделью Hooke element.
Using the asymptotic approximation of the maxwell element model for the analysis of stress in a conveyor belt
(ЧП "Технолог. центр", 2021) Pihnastyi, Oleh; Cherniavska, Svitlana
The features of the propagation of dynamic stresses in a conveyor belt, the material properties of which correspond to the Maxwell element model, are considered. Analytical expressions are presented for calculating the dynamic elastic modulus, the loss modulus, and the angle of technical loss depending on the frequency of longitudinal oscillations in the belt of an extended transport conveyor. To analyze the dynamic stress propagation process, dimensionless parameters are introduced that characterize the specific features of the viscoelastic process in a conveyor belt, the material properties of which correspond to the Maxwell element model. The transition to the dimensionless Maxwell element model is made and the analysis of the relationship between stress and deformation of a conveyor belt element for extremely large and small values of dimensionless parameters is made. The substantiation of the scope of the Maxwell element model is given. It is shown that at sufficiently high frequencies of longitudinal stress oscillations in a conveyor belt, at which the oscillation period is much less than the characteristic oscillation decay time, the relationship between stress and deformation of the conveyor belt element corresponds to Hooke’s law. A qualitative analysis of the relaxation time was carried out for a conveyor belt material, the properties of which correspond to the Maxwell element model. The analysis of the propagation of dynamic stresses in the conveyor belt for the characteristic operating modes of the transport conveyor is carried out. The conveyor operating mode with a constant deformation rate of the belt element; the mode in which a constant load is suddenly applied to the belt element; the conveyor operating mode with an instantly applied load to the belt element was investigated. It was determined that in cases where the characteristic process time significantly exceeds the stress relaxation time in the conveyor belt or the longitudinal oscillation period is much less than the stress relaxation time in the conveyor belt, the Maxwell element model can be replaced with a sufficient degree of accuracy by the Hooke element model
Effective Conveyor Belt Control Based on the Time-Of-Use Tariffs
(2020) Pihnastyi, O. M.; Kozhevnikov, G. K.
The paper proposes a method for constructing an algorithm for the speed control of a conveyor belt, based on the change in the price of electricity during the day. The analysis of methods for improving the energy efficiency of conveyor-type distributed transport systems is carried out. The influence of the uneven distribu-tion of material along the transportation route on the cost of transportation of a unit weight of the material is demonstrated. The advantages of using Time-Of-Use (TOU) tariffs when designing belt speed control systems for long conveyor systems are considered. The TOU periods with peak, standard and low energy consumption depending on time are presented in detail, as well as the values of the tariff coefficients for the TOU periods. The dependence of the value of the tariff coefficient on time is an essential factor that must be taken into account when designing control algorithms. When developing the control algorithm, it was assumed that the resistance to motion in accordance with DIN 22101 is de-termined on the basis of the primary friction coefficients. To describe a separate section, an analytical model of the conveyor in a dimensionless form was used. The problem of constructing an optimal algorithm for controlling the speed of a conveyor belt for a steady-state is formulated. The criterion of the quality of the control process in the conditions of using a constant amount of electricity during the day has been determined. The Pontryagin function and the conjugate system of equations are written, taking into account the uneven distribution of material along the transport route.
Kelvin-Voigt Model of Dynamic Stress in the Conveyors’ Belt
(2020) Pihnastyi, O. M.; Kozhevnikov, G. K.
The paper considers the reasons for the occurrence of dynamic stresses in a conveyor belt made of composite materials, the properties of which can be described by the Kelvin-Voigt model of an elastic element. A boundary value problem for the equation of elastic vibrations in a lightly loaded conveyor-type transport system is formulated. The dependencies determining the forces of resistance to the movement of the belt correspond to the recommendations of DIN 22101: 2002-08. An expression is presented that determines the speed of propagation of disturbances in the conveyor belt, taking into account the uneven distribution of material along the transport route. The reasons for the appearance of elastic stresses in the conveyor belt associated with the start, acceleration, deceleration and stop of the transport conveyor are demonstrated. Dimensionless parameters were introduced to analyze the causes of dynamic stresses in the conveyor belt. Similarity criteria in the dimensionless transport conveyor model make it possible to use the results obtained for similar transport systems. It is shown that the value of static stresses for lightly loaded transport systems is characterized by a linear dependence on the distance between the belt element and the drive shaft of the conveyor section. The solution of the boundary value problem defining the expression for dynamic stresses in the tape is presented. It is shown that the decay speed of the arising disturbances is inversely proportional to the value of the viscosity coefficient of the composite material, which characterizes the mechanical properties of the conveyor belt. A qualitative assessment has been made for the characteristic decay time of dynamic disturbances in a conveyor belt.
Development of the controlling speed algorithm of the conveyor belt based on TOU tariffs
(2020) Pihnastyi, O. M.; Khodusov, V. D.
The article considers the synthesis of an optimal discrete control algorithm for the conveyor belt speed, based on the use of Time-Of-Use tariffs. Methods have been investigated that reduce the consumption of electricity required to transport material from the extracted place to the place of processing. It is shown that the uneven distribution of material along the transportation route for long multi-section conveyors leads to a significant increase in the share of transportation costs among the total costs of material extraction. The systems for controlling the flow parameters of the transport system are analyzed to ensure uniform distribution of material along the transport route and reduce the cost of transporting material. It has been demonstrated that energy management methodology is an effective tool to reduce the cost of material transportation. Analyzed the common classes of tariffs using electricity by industrial enterprises, which can be successfully used in the design of control systems for flow parameters of the conveyor line. When synthesizing algorithms for regulating the speed of the belt, the model of primary friction and the assumption of the absence of a stress wave in the belt during instantaneous switching of the speed modes were used. An analytical model of the conveyor is presented in a dimensionless form, taking into account the transport delay. The problem of optimal control of the speed of the conveyor belt at fixed energy consumption for the considered control interval is formulated. The ranges of variation of the model parameters are estimated. An algorithm for optimal regulation of the belt speed using the coefficients Ukraine – TOU periods is synthesized. The influence of the initial conditions on the belt speed control modes is analyzed.