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Articles 121 - 150 of 225
Full-Text Articles in Controls and Control Theory
Synthesis Methods And Algorithms For Expanding The Dynamic Range Of The Adc, Jumaev Odil Abdujalilovich, Rashidov G'Olibjon Xayriddinovich
Synthesis Methods And Algorithms For Expanding The Dynamic Range Of The Adc, Jumaev Odil Abdujalilovich, Rashidov G'Olibjon Xayriddinovich
Chemical Technology, Control and Management
The modern development of new technologies, in particular, the intensive use of programmable logic integrated circuits in digital information processing tasks, allows for algorithmically and programmatically solving problems, opens up real opportunities to increase accuracy and ensure the required signal conversion speed, and also, it will be possible to take into account the effects of noise and their elimination over the entire time interval band. The article discusses the main methods of digital information processing, analyzes the ways and possibilities of expanding the dynamic range of analog-to-digital converters, as well as the synthesis of appropriate conversion devices, primarily digital filters.
Mathematical Description Of A Bleach Impregnation Reservoir, Bekobod Ibragimov
Mathematical Description Of A Bleach Impregnation Reservoir, Bekobod Ibragimov
Chemical Technology, Control and Management
This article discusses the issues of constructing a mathematical model of the technological process of bleaching textile materials in an impregnating reservoir using the heat balance equation, on the basis of which a qualitative analysis of the dynamic properties of an object has been carried out in order to create highly efficient control systems with the use of energy-saving technologies. While constructing a mathematical model characterizing the established and non-established modes of the control object (impregnating reservoir) used changes in heat flow and mass velocity of the incoming tissue. An algorithm for constructing a mathematical model of the process of …
Mathematical Description And Algorithm For Solving The Model Of The Ionite Regeneration Process In The Ion Exchange Method Of Water Softening, Djalolitdin Paxritdinovich Mukhitdinov, Nilufar Abdusami Qizi Yunusova
Mathematical Description And Algorithm For Solving The Model Of The Ionite Regeneration Process In The Ion Exchange Method Of Water Softening, Djalolitdin Paxritdinovich Mukhitdinov, Nilufar Abdusami Qizi Yunusova
Chemical Technology, Control and Management
Based on the modern representation of the water softening process by the ion exchange method, modeling was carried out, an algorithm was developed and the ionite regeneration process was calculated in a water softening plant with a fixed ionite layer. To solve the system of equations of the model, special, but simple enough for use in engineering calculations, techniques and methods have been developed and applied. The constructed model and its solution algorithm can be used to predict the process of ionite regeneration in an ion exchange apparatus. It can also be used to calculate the time of the ionite …
Modeling And Adjustment Of A Fuzzy Controller In A Bioreactor Control System, Mahmudov Giyosjon Baqoyevich
Modeling And Adjustment Of A Fuzzy Controller In A Bioreactor Control System, Mahmudov Giyosjon Baqoyevich
Chemical Technology, Control and Management
The article describes the modeling and configuration of a fuzzy controller for the control system of the bacterial oxidation of hard-to-enrich gold-bearing sulfide ores. The simulated logical fuzzy controller allows you to save the consumption of refrigerant water consumed in the process by 4,3%, using it to control the process of bacterial oxidation.
Synchronization Of The Training Of Specialists In The Automation Of Technological Processes In Accordance With The Dynamics Of The Taxonomy Of Learning Goals, Yusuf Shodievich Avazov, Kamola Abdullaeva
Synchronization Of The Training Of Specialists In The Automation Of Technological Processes In Accordance With The Dynamics Of The Taxonomy Of Learning Goals, Yusuf Shodievich Avazov, Kamola Abdullaeva
Chemical Technology, Control and Management
Changes in the characteristics of modern ones, reflecting them as the "digital generation", inevitably necessitate electronic interactive, mobile and mixed, machine learning, especially in the field of automation and control of technological processes and production. As a consequence of reflecting these realities, there have been parallel changes in the taxonomy of learning objectives - from the classical to the revised rethought and digital.
In order to study the problem of synchronizing the training of future specialists in the field of automation and control of technological processes and production and funny knowledge in accordance with the dynamics of the taxonomy of …
Algorithmic Methods For Developing The Structure Of A Thyristor Electric Drive For Mining Machines, N.R Yusupbekov, O.A. Jumaev, S.S. Turaev
Algorithmic Methods For Developing The Structure Of A Thyristor Electric Drive For Mining Machines, N.R Yusupbekov, O.A. Jumaev, S.S. Turaev
Chemical Technology, Control and Management
The article discusses the creation of algorithmic structures and the development of digital control systems for electric drives of mine-lifting machines, provides some concepts for creating digital control systems using thyristor converters. The analysis of the static volt-ampere characteristics of the thyristor is given, some calculations of the circuits and circuits of the thyristor converter (TP) corresponding to the different modes of operation of the TP are given, and also, based on the synthesis of the dynamic properties and characteristics of the thyristor, an algorithmic structure of the model of the thyristor converter is proposed.
Modeling Of The Process Of Measuring Conversion Of The Flow Of Liquid And Gaseous Media By The Method Of Variable Pressure Drop, Shukhrat Manapovich Gulyamov, Elbek Elmirza O'G'Li Ortiqov
Modeling Of The Process Of Measuring Conversion Of The Flow Of Liquid And Gaseous Media By The Method Of Variable Pressure Drop, Shukhrat Manapovich Gulyamov, Elbek Elmirza O'G'Li Ortiqov
Chemical Technology, Control and Management
On the basis of material and heat balances, taking into account the initial and boundary conditions, a mathematical model of the process of measuring the transformation of liquid and gaseous technological media by the method of variable pressure drop is constructed. The analysis of the results of studying the influence of non-stationary flows of a controlled medium on the uncertainty of the results of measuring the flow rate of liquids and gaseous mixtures with a changing hydrodynamic structure of the flow of a controlled medium is performed. A comparative analysis of the calculated and experimental transient processes in the measuring …
Model For Calculating The Static Characteristics Of Hydraulic Systems Of Hydro Technical Buildings, Mirkhalil Ismailov, Dong Zhang, Farkhod Kasimov
Model For Calculating The Static Characteristics Of Hydraulic Systems Of Hydro Technical Buildings, Mirkhalil Ismailov, Dong Zhang, Farkhod Kasimov
Chemical Technology, Control and Management
Hydraulic mechanisms that actuate flat gates, widely used in hydraulic structures, are studied as hydraulic actuators of the system. Their static mathematical models are developed using an integrated methodology with a hydraulic pump, inlet and suction pipes, and internal and external resistance factors. Unlike existing mathematical models, the model developed in this paper allows a detailed description of the characteristics of hydraulic drives due to the fact that pressure losses in the throttle, regulator, and power amplifier, as well as local resistances in hydraulic pipelines, are taken into account.
Analysis Of Vegetable Oil Refining Technology, Elyor Samadov
Analysis Of Vegetable Oil Refining Technology, Elyor Samadov
Chemical Technology, Control and Management
Innovative technologies for refining vegetable oils are presented, as well as the qualitative characteristics of raw vegetable oils obtained by extraction and mechanical methods. A general review of the chemical composition and impurities of vegetable oils resulting from the reaction between glycerol and fatty acids is carried out, and a brief review of the study to determine the effect of refining on biologically active components.
The analytical review is devoted to a comparative comparison of two types of refining - chemical and physical refining.
Influence Of Magnetomechanical Properties Of Ferromagnetic Materials On The Sensitivity Of A Magnetoelastic Sensor, Sulton Amirov, Kamila Komilovna Jurayeva
Influence Of Magnetomechanical Properties Of Ferromagnetic Materials On The Sensitivity Of A Magnetoelastic Sensor, Sulton Amirov, Kamila Komilovna Jurayeva
Chemical Technology, Control and Management
The requirements of high operational reliability are most fully met by automated monitoring and control systems, the elements of which are magnetoelastic sensors. Such sensors, due to their metrological characteristics, have found application in electrified railway transport, in the metallurgical, metalworking, mining and other industries. The principle of operation of such sensors is based on the fact that in the process of influencing the magnetic core of the sensor by force, there is a change in the magnetic permeability of the material, a change in the magnetic resistance of the circuit, a change in the mutual inductance coefficient of the …
Algorithms For Multi-Factory Polynomial Modeling Of Technological Processes, Farrukh Do'stmirzayevich Jo'rayev, Murodjon Ashurqulovich Ochilov
Algorithms For Multi-Factory Polynomial Modeling Of Technological Processes, Farrukh Do'stmirzayevich Jo'rayev, Murodjon Ashurqulovich Ochilov
Chemical Technology, Control and Management
The article reveals the meaning and essence of the modeling method in the study of complex technological processes based on the problematic aspects of building multifactorial relationships and the principles for their elimination. In the case of non-linearity of multifactorial connections of a complex system, the expediency of approximating such functions by polynomials is substantiated. The authors' ideas about the increasing importance of interpolation methods in practice against the background of the possibility of simplification based on the use of modern mathematical hardware and software for integration into the process of modeling and optimizing technological processes due to the complexity …
Structural Model Of The Technological Process Of Storage And Processing Of Oil Raw Materials, N.A Kabulov
Structural Model Of The Technological Process Of Storage And Processing Of Oil Raw Materials, N.A Kabulov
Chemical Technology, Control and Management
The technological method of storing and processing oilseed raw materials is structurally modelled in the article. Additionally, it is suggested that the generalized structure be presented as a three-part scheme, consisting of a raw material department, a processing shop, and transportation networks. On the basis of a thorough examination of the characteristics of the constituent parts of the technological complex, a practical model for the problem of the general characteristics of the technological complex is proposed.
Predictive Analysis And Synthesis, Modeling And Control Of Complex Technological Processes And Systems, Zhahongir Sherboyevich Bekqulov
Predictive Analysis And Synthesis, Modeling And Control Of Complex Technological Processes And Systems, Zhahongir Sherboyevich Bekqulov
Chemical Technology, Control and Management
Consider the theoretical underpinnings of practically predictive analysis and synthesis, modeling and automatic control of complex chemical technological processes and systems, and the evolution of advanced (or advanced) APC (Advanced Process Control) control of technological processes and industries. The current state of industrial automation systems and the characteristics of their deployment are highlighted. The features of each stage of the analysis and synthesis of APC - advanced process control for complex dynamic objects are disclosed. The real situation and features of the implementation of industrial automation systems of industrial enterprises are reflected.
Algorithm For Calculating The Parameters Of A Multi-Position Electromagnetic Linear Mechatronic Module, Nazarov Khayriddin Nuritdinovich, Matyokubov Nurbek Rustamovich, Temurbek Omonboyevich Rakhimov
Algorithm For Calculating The Parameters Of A Multi-Position Electromagnetic Linear Mechatronic Module, Nazarov Khayriddin Nuritdinovich, Matyokubov Nurbek Rustamovich, Temurbek Omonboyevich Rakhimov
Chemical Technology, Control and Management
Currently, in the world in the field of science, engineering and technology, including in mechatronics and robotics, the creation of multi-coordinate mechatronic systems that perform power and control functions is becoming of paramount importance, this is due to a number of important positive qualities of the systems, such as simplicity and compactness of the design, the possibility of obtaining significant efforts, high accuracy and stability of the establishment of fixed positions, ease of control and high reliability. This article presents the calculation of the parameters of multi-position mechatronic modules based on linear execution elements. In the construction of this model, …
New Transformer Changer Static Characteristics Measuring Angle Silences Difference, Sultan Faizullayevich Аmirov, Nurulla Raxmatullayevich Yuldashev
New Transformer Changer Static Characteristics Measuring Angle Silences Difference, Sultan Faizullayevich Аmirov, Nurulla Raxmatullayevich Yuldashev
Chemical Technology, Control and Management
Presented the specific features of the new transformer converter, which measures the difference in angular displacement, and examines the nonlinearity levels of static characteristics, sensitivity and static characteristics. Studies have shown that in a new measuring device, where one of the two moving parts consists of a magnetic conductor made in the form of an Archimedean spiral made of ferromagnetic material, the balance of the magnetic bridge changes not only depending on the angle of rotation of it’s shoulder resistances. the current is disturbed by the change in the magnitude of the combined air gap depending on the angle of …
Design Lifecycle Management Of Technological Processes, Yusuf Shodiyevich Avazov
Design Lifecycle Management Of Technological Processes, Yusuf Shodiyevich Avazov
Chemical Technology, Control and Management
The issues of life cycle management of design processes of complex technological processes are considered. An analysis of works devoted to the automated design of technological processes and industries, product life cycle management, and the use of predominant modeling in design is presented. A structure for the implementation of the design of technological processes is proposed and it’s components are described. An algorithm is proposed to reduce the life cycle of the design of a technological process. The sequence of selection of the most optimal project options with the help of the proposed algorithm is described. It is shown that …
Developing Advanced Process Control System For Manufacturing Processes Using Virtual Analyzer, Elyor Erkinovich Samadov
Developing Advanced Process Control System For Manufacturing Processes Using Virtual Analyzer, Elyor Erkinovich Samadov
Chemical Technology, Control and Management
This research reflects outlines the main potential features of Advanced Process Control (APC) systems for improved control of technological processes and production. It is shown developing APC systems using a virtualized analyzer (VA) is a very effective technique to increase the efficiency of industrial production. This research reflects the main steps of generating VA as part of the APC system and also describes the key features of each step-in terms of analyzer synthesis.
Mathematical Modeling Of Processes Of Diagnostics Of Technical And Technological Objects, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev
Mathematical Modeling Of Processes Of Diagnostics Of Technical And Technological Objects, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev
Chemical Technology, Control and Management
The work is an introduction to the technical diagnostics of technical (or technological) objects. It discloses the basic concepts and definitions of the reliability of dynamic systems as objects of diagnostic reference knowledge and their diagnosis. Structural schemes of diagnosing objects with individual and combined channels of influence are analyzed. Questions of rational construction of base of reference knowledge are stated.
Uncertainty Of The Ultrasonic Method For Determining The Strength Of Concrete, Ortagoli Sharipovich Hakimov, Zamira Khudoyberdiyevna Ernazarova
Uncertainty Of The Ultrasonic Method For Determining The Strength Of Concrete, Ortagoli Sharipovich Hakimov, Zamira Khudoyberdiyevna Ernazarova
Chemical Technology, Control and Management
The issues of measuring the strength of concrete by the method of surface sounding by ultrasound are considered. A measurement model and formulas for estimating the total standard measurement uncertainty, information about the standards used, measurement tools and methods, and environmental parameters are given. Information about the estimation of uncertainty in the form of "eight steps", such as: measurement task; mathematical model of measurement; analysis of input values; observation results; correlations; uncertainty budget; expanded uncertainty; measurement result. It has been established that the uncertainty of type B of the ultrasonic method for determining the strength of concrete is much less …
Quality Control Of Combustion Of Gaseous Fuel In Furnaces, Azamat Toirovich Rajabov
Quality Control Of Combustion Of Gaseous Fuel In Furnaces, Azamat Toirovich Rajabov
Chemical Technology, Control and Management
The issues of research and development of systems for monitoring the availability and quality of the process of fuel combustion in industrial furnaces are interpreted. The perspective of using new elements in control systems - communication sensors for the presence and quality in gas-burning installations and furnaces are shown. A method has been developed to control the optimal aeration coefficient based on the extreme of the total integral amplitude-frequency characteristic of the flame conductivity pulsations, which makes it possible to control the quality characteristics of gas-burner devices and control the ratio of the components of the combustible mixture with high …
Regular Algorithms For Adaptive Identification Of Linear Non-Stationary Systems, H.Z. Igamberdiyev, H.I. Sotvoldiev, U.F Mamirov
Regular Algorithms For Adaptive Identification Of Linear Non-Stationary Systems, H.Z. Igamberdiyev, H.I. Sotvoldiev, U.F Mamirov
Chemical Technology, Control and Management
The article deals with the formation of regular algorithms for adaptive parametric spline identification of linear non-stationary systems. Analyzed the issues of constructing adaptive identification of continuous linear non-stationary systems with monotonic and sign-constant parameters. In this case, in a non-stationary system, the entire observation interval is in some way divided into sub-intervals. Identification is carried out at each of the parameter constancy intervals, while the parameter matrix is re-evaluated for the next interval. The input data of the system are determined with an error depending on the error of approximating the state of the system by splines and approximating …
Information Software And Devices For Energy Efficiency Management And Control, Narzullo Nuriddinovich Mirzoyev
Information Software And Devices For Energy Efficiency Management And Control, Narzullo Nuriddinovich Mirzoyev
Chemical Technology, Control and Management
The article provides information on modern methods of management and control of energy efficiency at industrial enterprises. This includes the software needed to manage and monitor energy efficiency, as well as the formation of a database. In addition, a structural diagram of an intelligent power monitoring system has been developed and its elements have been selected. Describes the principle of operation of an intelligent measuring device, its connection to the network, conversion of analog signals to digital, channels and ranges of signal transmission, metrological characteristics. The article details the capabilities and benefits of smart meters.
Analysis Of Water Treatment Methods For Circulating Water Supply In Industrial Plants, Djalolitdin Paxritdinovich Mukhitdinov, Nilufar Abdusomi Kizi Yunusova
Analysis Of Water Treatment Methods For Circulating Water Supply In Industrial Plants, Djalolitdin Paxritdinovich Mukhitdinov, Nilufar Abdusomi Kizi Yunusova
Chemical Technology, Control and Management
This scientific paper deals with the problem of extracting Ca2+ and Md2+ salts from water in order to prevent the formation of scale on the heating surfaces of heat exchange equipment. The features, advantages and disadvantages of chemical, membrane and ion exchange methods of water treatment have been evaluated. It has been shown that the chemical method of water purification can be used only for the preparation of industrial water at large stations (at the same time, high residual hardness prevails in the water, the equipment has low productivity), and the membrane method requires pretreatment of water, creation of overpressure …
Ultrasonic Extraction Of Instant Forms Of Plant Substrates In Industrial Production, Shakhnoza Abduvaxitovna Sultanova, Jasur Safarov, Azamat Bakir O'G'Li Usenov, Doston Ishmuhammat Ogli Samandarov, Qobil Akmal Ogli Mukhiddinov
Ultrasonic Extraction Of Instant Forms Of Plant Substrates In Industrial Production, Shakhnoza Abduvaxitovna Sultanova, Jasur Safarov, Azamat Bakir O'G'Li Usenov, Doston Ishmuhammat Ogli Samandarov, Qobil Akmal Ogli Mukhiddinov
Chemical Technology, Control and Management
In recent years, both in our country and abroad, ultrasonic extraction methods have been increasingly used in industrial production, which is associated with the extraction of various substances and compounds from natural plant substrates. Domestic and foreign experience shows that this method has significant advantages over traditional methods and can significantly increase the efficiency and profitability of industrial enterprises, producing complete and functional food products.
This article discusses a brief theory of ultrasonic cavitation and the experience of extracting substrates from plants. Different results have been compared and analyzed.
Analysis Of Grain Product Drying Methods, Azizbek Nodirbekovich Yusupbekov, Dilmurod Egamberganov
Analysis Of Grain Product Drying Methods, Azizbek Nodirbekovich Yusupbekov, Dilmurod Egamberganov
Chemical Technology, Control and Management
Various drying methods and grain characteristics have been studied. The advantages and disadvantages of various grain drying methods were obtained. The use of the following methods of drying grain products is very useful for speeding up the drying process, reducing waste, achieving more flexible process management and delivering all the nutrients of dried grain and grain products to the subsequent production process. The technological approaches that increase the efficiency of high-quality production after drying grain products, the requirements for modern grain dryers have analyzed. The ways of overcoming the problem of high energy consumption in the process of drying grain …
Implementation Of Distance Learning At Universities Using The Experience Of The Honeywell Process Control Laboratory At Tashkent State Technical University, Nodirbek Rustambekovich Yusupbekov, Adilov Tulkunovich Farukh, Isakova Ismailovna Sitora
Implementation Of Distance Learning At Universities Using The Experience Of The Honeywell Process Control Laboratory At Tashkent State Technical University, Nodirbek Rustambekovich Yusupbekov, Adilov Tulkunovich Farukh, Isakova Ismailovna Sitora
Chemical Technology, Control and Management
The experience of modernization of the Honeywell Process Control Laboratory at Tashkent State Technical University has been considered (which is equipped with upgraded equipment (simulators for simulating various technological processes, distance learning tools). As a result, the quality of the demonstration of process control mechanisms increased the availability of theoretical and practical knowledge in the field of automated control systems. They also considered the teaching methods necessary for a modern student – remote access in real time, when students pass a knowledge test, consult with teachers, etc.
Error Of Contactless Converters Of High Currents Of Monitoring And Control Systems From The Influence Of Currents Of Neighboring Buses, A.M. Plakhtiev, Gayratjon Gaziev, Y.A. Meliboev, O. Doniyorov
Error Of Contactless Converters Of High Currents Of Monitoring And Control Systems From The Influence Of Currents Of Neighboring Buses, A.M. Plakhtiev, Gayratjon Gaziev, Y.A. Meliboev, O. Doniyorov
Chemical Technology, Control and Management
The article presents the general principles of construction of contactless ferromagnetic converters of large direct currents, the main requirements for them, and the results of the development of one of the developed wide-range magnetomodulation contactless converters of control and control systems concerning large electric power facilities. The developed converter, unlike the known ones, have a wide range of controlled currents, increased accuracy and sensitivity, a technological design, and small weight and dimensions at low material consumption and cost. The errors of contactless wide-range magnetomodulation converters from the influence of currents of neighboring buses connected by and the opposite direction are …
Implementation Of The Pid Control Law Of A Multidimensional Dynamic System, Khurshid Salim Ugli Turayev
Implementation Of The Pid Control Law Of A Multidimensional Dynamic System, Khurshid Salim Ugli Turayev
Chemical Technology, Control and Management
Most industrial automation facilities are multi-circuit with a significant influence of cross-links between the goals. The paper develops a system for automatic parameter adjustment of a programmable logic controller that implements the proportional-integral-differential control law of a multidimensional dynamic object. The issues of decentralized management of multidimensional dynamic objects are discussed. The control system is based on the method of independent synthesis with static compensation of the impact of cross-links. Additional software has been developed to determine the parameters of the control system. After setting the necessary parameters, the process of automatic adjustment of the controller parameters starts. Self-tuning procedures …
Problems Of Modeling And Control Of The Technological Process Of Ore Grinding, Djalolitdin Pakhritdinovich Mukhitdinov, Sanjar Boybutayev
Problems Of Modeling And Control Of The Technological Process Of Ore Grinding, Djalolitdin Pakhritdinovich Mukhitdinov, Sanjar Boybutayev
Chemical Technology, Control and Management
The article analyzes the methods of mathematical modeling of the closed-loop process of fine grinding of ore in order to predict the composition of the crushed raw material. Analyzed modeling methods that consider the control of classification of crushed raw materials and finished products by the size of the recirculating load, simulation modeling methods, methods that use neuro-phase netthe research apparatus, in which the fuzzy logic apparatus serves as a fundamental component for the formation of conclusions. The materials presented in the article reflect the theoretical substantiation and generalization of the accumulated practical experience in modeling and control of the …
Structural-Parametric Analysis And Synthesis Of Control Systems With Two Degrees Of Freedom, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev
Structural-Parametric Analysis And Synthesis Of Control Systems With Two Degrees Of Freedom, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev
Chemical Technology, Control and Management
Automatic tuning of the parameters of PID - regulators is proposed by means of a modified experiment that takes into account the influence of elements and circuits in the form of additive uncertainty. The use of a multiply connected control scheme with two degrees of freedom for decoupling is proposed in order to facilitate the implementation of a mechanism for combating the phenomenon of integral saturation. Equations are derived for the transition from a circuit with one degree of freedom to a circuit with two degrees of freedom for the general and special cases of a two-dimensional system, which makes …