Open Access. Powered by Scholars. Published by Universities.®

Operations Research, Systems Engineering and Industrial Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Process Control and Systems

Institution
Keyword
Publication Year
Publication
Publication Type

Articles 181 - 210 of 309

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Analysis Of Vegetable Oil Refining Technology, Elyor Samadov Feb 2023

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.


Research Of Three-Phases Current’S Transducers Of Filter-Compensation Devices For Control Reactive Power’S Consumption Of Asynchronous Motor, Ilkhomjon Khakimovich Siddikov, Dilyorbek Karimjonov Doniyorbek O'G'Li -, Abdumutal Abdikarimovich Abdigapirov Feb 2023

Research Of Three-Phases Current’S Transducers Of Filter-Compensation Devices For Control Reactive Power’S Consumption Of Asynchronous Motor, Ilkhomjon Khakimovich Siddikov, Dilyorbek Karimjonov Doniyorbek O'G'Li -, Abdumutal Abdikarimovich Abdigapirov

Chemical Technology, Control and Management

In the article given materials of developing of three-phase electromagnetic current transducers of reactive power, using with asynchronous motor, methods connecting of two sensing element, series, parallel and differential and loops suitable for each phase, dynamic characteristics of output signals of three-phase electromagnetic current transducers asynchronous motor.

On the basis of modern calculation and design complexes are of great importance in the research variable sizes of three-phase current electromagnetic transducers of filter-compensation devices of reactive power of asynchronous motors. Presented mathematical model of research of electrical, electromagnetic and magnetic elements of electromagnetic current transducers in the …


Towards Lean Manufacturing In Developing Countries: Research Gaps And Directions In Tanzania, Francis D. Sinkamba Feb 2023

Towards Lean Manufacturing In Developing Countries: Research Gaps And Directions In Tanzania, Francis D. Sinkamba

Tanzania Journal of Engineering and Technology (TJET)

In the current knowledge-driven economy, many industries across the globe are forced to adopt manufacturing technologies such as lean manufacturing to remain competitive in the globalized world. Despite the increase in lean manufacturing implementations, the adoption rate in Tanzania is very low and estimated to be 8 percent. Likewise, the sustainability of lean manufacturing tools and practices is still questionable, which shows the need to develop lean maturity models. To date, several lean maturity models have been developed but there is ARTICLE INFO Submitted: July 5, 2022 Revised: Sept. 28, 2022 Presented: Oct. 20, 2022 a lack of maturity models …


Factors Influencing Total Productive Maintenance Implementation For Thermal Generation Plants, Ismail W. R. Taifa Dr Feb 2023

Factors Influencing Total Productive Maintenance Implementation For Thermal Generation Plants, Ismail W. R. Taifa Dr

Tanzania Journal of Engineering and Technology (TJET)

This study accepts that the technical and administrative factors can amplify effective total productive maintenance (TPM) implementation at thermal generation plants. It is noted that there is a limited number of studies that have attempted to understand the subject of TPM implementation in the energy sector. Noting this shortcoming, the authors thought it crucial to generate empirical evidence on the factors influencing effective TPM implementation for thermal generation plants, with evidence from gas-fired plants. A sample of 88 respondents was selected and consulted. Data were collected through questionnaires and analyzed quantitatively by inferential statistics and qualitatively through thematic analysis using …


Current And Future Trends Of Construction Project Performance Models: A Review, Method Mtana Feb 2023

Current And Future Trends Of Construction Project Performance Models: A Review, Method Mtana

Tanzania Journal of Engineering and Technology (TJET)

The construction industry (CI) has experienced outstanding growth and contributed to economic growth for many countries, with enormous foreign investments that require quality projects. High pressure to reduce the construction cost and time commonly put the industry at risk of lower quality and safety of the construction facilities. Like many other developing countries, Tanzania needs more stringent quality control measures in the construction sector to contribute positively to sustainable growth. This study thus reviews current and future trends in construction industry performance in Tanzania. The literature review on construction projects (CPs) performance is based on information on time overruns from …


Towards The Development Of A Framework For Assessing Organizational Governance Maturity For Technical Audit Of Public Works, George Haule Feb 2023

Towards The Development Of A Framework For Assessing Organizational Governance Maturity For Technical Audit Of Public Works, George Haule

Tanzania Journal of Engineering and Technology (TJET)

The quality of the audit work and its products is often associated with the organizational maturity of the audit function. The absence of a well-defined organizational maturity for an audit function leads to poor quality of audit work or products and ineffective audit function. The lack of a framework for measuring governance maturity was identified as a major deterrent factor to the attainment of quality audit work. Measuring the governance maturity of the technical audit of public works is challenging due to the absence of a maturity framework that fits its needs. The noted shortcomings include: (a) existing maturity frameworks …


Designing And Manufacturing Of Vegetable Slicing Machine, Juma Nuhu Msuya Feb 2023

Designing And Manufacturing Of Vegetable Slicing Machine, Juma Nuhu Msuya

Tanzania Journal of Engineering and Technology (TJET)

Agro-processing industry is faced with a challenge of slicing of vegetables for immediate consumption. This stems from the fact that the traditional slicing methods use bare hands, and knives. This method is faced with shortcomings of inefficiency, poor hygiene, and significant dangers to injury. If vegetables are not sliced, their drying takes longer, may possibly be spoiled, and cannot be stored for future uses. Therefore, this paper strives to design a vegetable slicing machine to increase the efficiency of the drying process as a post-processing step. The study employed a Pugh’s design model to design the machine and manufacture it. …


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 Feb 2023

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 …


Virtual Potassium Chloride Analyzer In The System Of Advanced Control Of Potash Fertilizer Production Processes, Umidjon Ruziev, Jahongir Sherboyevich Bekqulov Feb 2023

Virtual Potassium Chloride Analyzer In The System Of Advanced Control Of Potash Fertilizer Production Processes, Umidjon Ruziev, Jahongir Sherboyevich Bekqulov

Chemical Technology, Control and Management

It is proposed to include virtual instrumental quality analyzers of potash fertilizers in the composition of the advanced (advanced) management system. The structure of the virtual analyzer is substantiated using mathematical models of the technological process of drying potassium chloride in its composition. Based on the results of fuzzy clustering, the parameters of the modes of the technological process of drying potassium chloride are determined.


Influence Of Magnetomechanical Properties Of Ferromagnetic Materials On The Sensitivity Of A Magnetoelastic Sensor, Sulton Amirov, Kamila Komilovna Jurayeva Feb 2023

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 …


Algorithmic Methods For Developing The Structure Of A Thyristor Electric Drive For Mining Machines, N.R Yusupbekov, O.A. Jumaev, S.S. Turaev Feb 2023

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.


Algorithms For Multi-Factory Polynomial Modeling Of Technological Processes, Farrukh Do'stmirzayevich Jo'rayev, Murodjon Ashurqulovich Ochilov Feb 2023

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 Feb 2023

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.


Techno-Economic Analysis And Optimization Of Hydrogen And Mechanical Energy Storage Systems, Pavitra Senthamilselvan Sengalani Jan 2023

Techno-Economic Analysis And Optimization Of Hydrogen And Mechanical Energy Storage Systems, Pavitra Senthamilselvan Sengalani

Graduate Theses, Dissertations, and Problem Reports (ETD)

The increasing significance of renewable energy sources is thrusting the load cycling of fossil-fueled power plants (FFPP), designed to operate under nominal-load conditions. Integration of energy storage systems (ESS) with the FFPPs such as hydrogen energy storage (HES) and mechanical energy storage facility such as compressed air energy storage (CAES) shows the potential to minimize the levelized cost of electricity during high demand scenarios and also minimize the negative impacts of off-design FFPP operation. The deployment of energy storage facilities at the FFPP level have considerable potential advantages as they can be exploited within the existing equipment items and facilities …


Performance Evaluation Of Udsm Network To Deliver Multimedia Elearning Contents: Case Of Coict, Mercy Mbise Dec 2022

Performance Evaluation Of Udsm Network To Deliver Multimedia Elearning Contents: Case Of Coict, Mercy Mbise

Tanzania Journal of Engineering and Technology (TJET)

The use of technology in education in Sub-Saharan Africa has been reported to be hindered by many factors including inadequate Information and Communication Technology (ICT) infrastructure, low internet speed, and lack of skills to use educational technologies. This paper aim at evaluating how the available ICT infrastructure at the College of Information and Communication Technologies (CoICT) can support, with acceptable Quality of Service (QoS), the delivery of multimedia applications for eLearning services. The evaluation was performed over a network testbed implemented in a computer laboratory for wired and wireless connections. The testbed consisted of five personal computers (PCs) connected via …


Development Of Directed Randomization For Discussing A Minimal Security Architecture, Henrique Oyama, Dominic Messina, Keshav Kasturi Rangan, Akkarakaran Francis Leonard, Kip Nieman, Helen Durand, Katie Tyrrell, Katrina Hinzman, Michael Williamson Dec 2022

Development Of Directed Randomization For Discussing A Minimal Security Architecture, Henrique Oyama, Dominic Messina, Keshav Kasturi Rangan, Akkarakaran Francis Leonard, Kip Nieman, Helen Durand, Katie Tyrrell, Katrina Hinzman, Michael Williamson

Chemical Engineering and Materials Science Faculty Research Publications

Strategies for mitigating the impacts of cyberattacks on control systems using a control-oriented perspective have become of greater interest in recent years. Our group has contributed to this trend by developing several methods for detecting cyberattacks on process sensors, actuators, or both sensors and actuators simultaneously using an advanced optimization-based control strategy known as Lyapunov-based economic model predictive control (LEMPC). However, each technique comes with benefits and limitations, both with respect to one another and with respect to traditional information technology and computer science-type approaches to cybersecurity. An important question to ask, therefore, is what the goal should be of …


Cybersecurity And Dynamic Operation In Practice: Equipment Impacts And Safety Guarantees, Kip Nieman, Dominic Messina, Matthew Wegener, Helen Durand Nov 2022

Cybersecurity And Dynamic Operation In Practice: Equipment Impacts And Safety Guarantees, Kip Nieman, Dominic Messina, Matthew Wegener, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Though dynamic operation of chemical processes has been extensively explored theoretically in contexts such as economic model predictive control or even considering the potential for cyberattacks on control systems creating non-standard operating policies, important practical questions remain regarding dynamic operation. In this work, we look at two of these with particular relevance to process safety: (1) evaluating dynamic operating policies with respect to process equipment fidelity and (2) evaluating procedures for determining the parameters of an advanced control law that can promote both dynamic operation as well as safety if appropriately designed. Regarding the first topic, we utilize computational fluid …


On-Line Process Physics Tests Via Lyapunov-Based Economic Model Predictive Control And Simulation-Based Testing Of Image-Based Process Control, Henrique Oyama, Akkarakaran Francis Leonard, Minhazur Rahman, Govanni Gjonaj, Michael Williamson, Helen Durand Jun 2022

On-Line Process Physics Tests Via Lyapunov-Based Economic Model Predictive Control And Simulation-Based Testing Of Image-Based Process Control, Henrique Oyama, Akkarakaran Francis Leonard, Minhazur Rahman, Govanni Gjonaj, Michael Williamson, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Next-generation manufacturing involves increas- ing use of automation and data to enhance process efficiency. An important question for the chemical process industries, as new process systems (e.g., intensified processes) and new data modalities (e.g., images) are integrated with traditional plant automation concepts, will be how to best evaluate alternative strategies for data-driven modeling and synthesizing process data. Two methods which could be used to aid in this are those which aid in testing data-based techniques on-line, and those which enable various data-based techniques to be assessed in simulation. In this work, we discuss two techniques in this domain which can …


Lyapunov-Based Economic Model Predictive Control For Online Model Discrimination, Henrique Oyama, Helen Durand Apr 2022

Lyapunov-Based Economic Model Predictive Control For Online Model Discrimination, Henrique Oyama, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Economic model predictive control (EMPC) is a flexible control design strategy that can be modified to achieve many operating goals while also ensuring safe operation (e.g., by adding Lyapunov-based stability constraints to form Lyapunov-based EMPC, or LEMPC). Prior works have investigated LEMPC capabilities for achieving goals online beyond optimizing process economics, including aiding in model structure selection to benefit model-based control system design since the accuracy and quality of the process model are important for achieving an expected performance from such systems. This work further probes the capabilities of LEMPC to accomplish multiple objectives during process operation, including aiding in …


Uncertainty Of The Ultrasonic Method For Determining The Strength Of Concrete, Ortagoli Sharipovich Hakimov, Zamira Khudoyberdiyevna Ernazarova Dec 2021

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 …


Mathematical Modeling Of Processes Of Diagnostics Of Technical And Technological Objects, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev Dec 2021

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.


Virtual Analyzers For Increasing The Intelligence Of Industrial Process Control Systems, Umidjon Abdimajotovich Ruziev Phd, Marufjon Kobuljanovich Shodiev Dec 2021

Virtual Analyzers For Increasing The Intelligence Of Industrial Process Control Systems, Umidjon Abdimajotovich Ruziev Phd, Marufjon Kobuljanovich Shodiev

Chemical Technology, Control and Management

It is shown that the development and implementation of virtual analyzers of the quality of the final industrial products is an effective tool for increasing the efficiency of industrial production. The methodology and stages of development of virtual analyzers for predicting the quality of products, monitoring non-measurable or difficult-to-measure parameters of continuous and periodic technological processes are considered, and issues of supporting and adapting a virtual analyzer during its operation without restructuring are also considered.


Developing Advanced Process Control System For Manufacturing Processes Using Virtual Analyzer, Elyor Erkinovich Samadov Dec 2021

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.


Design Lifecycle Management Of Technological Processes, Yusuf Shodiyevich Avazov Dec 2021

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 …


Predictive Analysis And Synthesis, Modeling And Control Of Complex Technological Processes And Systems, Zhahongir Sherboyevich Bekqulov Dec 2021

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.


New Transformer Changer Static Characteristics Measuring Angle Silences Difference, Sultan Faizullayevich Аmirov, Nurulla Raxmatullayevich Yuldashev Dec 2021

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 …


Quality Control Of Combustion Of Gaseous Fuel In Furnaces, Azamat Toirovich Rajabov Dec 2021

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 …


Algorithm For Calculating The Parameters Of A Multi-Position Electromagnetic Linear Mechatronic Module, Nazarov Khayriddin Nuritdinovich, Matyokubov Nurbek Rustamovich, Temurbek Omonboyevich Rakhimov Dec 2021

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, …


Regular Algorithms For Adaptive Identification Of Linear Non-Stationary Systems, H.Z. Igamberdiyev, H.I. Sotvoldiev, U.F Mamirov Dec 2021

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 …


Control Of The Facial Design Process Of Innovative Developments, Yusuf Shodiyevich Avazov Oct 2021

Control Of The Facial Design Process Of Innovative Developments, Yusuf Shodiyevich Avazov

Chemical Technology, Control and Management

The role and place of visual design in the process of creating an innovative development have been stated. It is shown that the tasks of the face stage of the product life cycle are devoted to systemic issues, in the center of which is the resolution of the contradiction between the desired and the achievable. The first is determined by the need to create a new system of a higher level, and the achievable is determined by the level of development of science, technology and production technology, as well as by the conditions of operation and repair. The work is …