bluuebunny/crossref_metadata_2025 huggingface dataset:
Mathematical modeling and research of heat and moisture transfer processes in porous media
Authors: Ravshanov Normakhmad , Shadmanov Istam , Kubyashev Kurash , Khikmatullaev Sanjar
Published: June 2021

A mathematical model, numerical algorithm, solution, and results of the computational experiment on a computer are developed to predict the process of heat and moisture transfer in porous media, taking into account such factors as the internal heat and moisture release of a porous natural product on the example of raw cotton and its products of hulling, seeds of various crops. It also considers the effect of temperature and moisture content changes in the environment on the storage and drying of porous materials.

In this study, the developed mathematical support of the object under research makes it possible to predict the change in temperature and moisture content at arbitrary points of the porous body and serves to prevent the loss of quality and spontaneous combustion of materials under solar radiation and to analyze and make managerial decisions.

Based on the method of coordinate-wise splitting, a numerical algorithm for calculating three-dimensional heat and moisture transfer problems in areas of the parallelepiped type is presented. An implicit second-order difference scheme for calculating the required functions is presented.

Based on the numerical calculations performed, it was established that moisture and heat transfer and their exchange with the environment occurs in the upper layers of the cotton pile; in the inner layers, there is an increase in temperature and moisture due to the respiration of raw cotton and its seeds, which depends on the degree of moisture of the raw cotton and their products of hulling.
Mathematical model of water absorption area in intensive garden irrigation from the ground
Authors: Juraev Fazliddin , Karimov Galib
Published: June 2021

This article presents the results of field experiments to irrigate intensive gardens, located in water-scarce areas, from the soil with special piles. Experiments were conducted in Kagan district of Bukhara region in 2016 to determine the optimal procedure for in-soil irrigation of apple variety "Pinc lady" in the intensive orchard, established in 2016 at the farm "Siyavush Kamron FOOD" in cooperation with Turkey. In this case, a mathematical model was developed to determine the irrigation area corresponding to the radius of propagation of the roots of three-year-old trees and to calculate water consumption. This makes it possible to determine the norms of irrigation of intensive garden trees.

This method can be used to set half scrubby intensive gardens in such areas where water is insufficient and use energy-saving technologies in the future.
Development of technology for water concentration of brown coal without use and use of red waste in this process as a raw material for colored glass in the glass industry
Authors: Kucharov Azizbek , Xalilov Sanjar , Qurbonov Aziz , Yaxshiyeva Yulduz , Yuldashev Rezhabboy
Published: June 2021

The Angren coal mine has 2 billion tons of reserves of various grades of lignite that can be used as fuel, of which 2BR-B2 and 2BOMSSh-B2 lignite grades, which have 2 million tons of reserves, remain unusable due to poor quality and low combustion heat. [1]. To improve the quality of these coals, water treatment technology has been developed. Technological schemes, gravitational flotation methods were studied. The ash content of coal was reduced, and the heat of combustion was increased. Scientific results have been obtained to apply the mixture as a technological waste in the glass industry. In particular, the properties of raw materials for brown tara bottles were studied. The brown glass was obtained by adding the resulting mixture as a technological waste, and its properties were studied.
Dependence of the wetting rate of the loess base on the moisture conditions
Authors: Хujakulov Rustam , Normurodov U , Zaripov M , Abdurakhmonov U , Berdiev Mustafo
Published: June 2021

The increasing demand for improved irrigation systems in the world requires a more comprehensive and widespread study of the reliability and safety of hydraulic structures. In this regard, increasing the reliability during the operation of hydraulic structures of irrigation systems, especially on collapsible soils, is very important because loess subsidence soils are widespread globally, a significant part of loess rocks are also found in Central Asia, including the Republic of Uzbekistan. This article discusses the study of the features of the joint work of full-scale irrigation structures with their loess subsidence bases and the intense - deformative state of subsidence foundations during their joint work with hydraulic structures on irrigation canals of the Kashkadarya region.
Use of seismic insulation for seismic protection of railway bridges
Authors: Shermuxamedov Ulugbek , Shaumarov Said , Uzdin Aleksandr
Published: June 2021

The problem of seismic protection of the bridge for the conditions of Uzbekistan is considered. The bridge is located in an area with estimated seismicity of 9 points. It has massive high supports on a natural foundation and relatively small and light spans. When selecting seismic isolation, this made it possible to use the span structures as a dynamic damper for the support vibrations in the direction along the bridge. Due to the damping effect, it was possible to achieve that the seismic forces in the support in the presence of the superstructure were less than in the free support without the superstructure. At the same time, the rigidity of fastening the superstructure to the support increased in comparison with the rigidity of classical seismic isolation, which facilitated the design of the supporting elements.
Fire resistance of lightweight steel-concrete slab panels under high-temperature exposure
Authors: Rybakov Vladimir , Seliverstov Anatoly , Vakhidov Oybek
Published: June 2021

Lightweight steel concrete structures (LSCS) - an innovative energy-efficient building structure type that can be used both as load-bearing and as enclosing one. They consist of profiled steel - usually galvanized and cold-bent - filled with a monolithic foam concrete with a 400kg/m3 density and with fiber cement sheets sheathing. These structures can be used in industrial and civil buildings as internal and external bearing and enclosing wall structures and as slabs, energy-efficient roof covering. According to the LSCS production method, prefabricated panels (walls and slabs) and building site performed constructions are distinguished. The paper presents the testing results with the aim to determine the fire resistance limit of a slab panel fragment by bearing capacity (R), loss of integrity (E), loss of heat insulating capability (I) and fire hazard class. Two samples of a slab panel fragment were selected for the fire resistance high-temperature tests. The actual fire resistance limit of samples of the slab panel fragment is at least REI 60 with a uniformly distributed load 4 kN/m2.
The chemical reagents influence on the regulation of the powder composite materials setting time for construction purposes
Authors: Munavvarkhanov Zokirkhan , Soliyev Rustam , Boydadayev Murotbek
Published: June 2021

Additives were selected, and a method for modifying the structure of gypsum-containing materials for construction purposes and a method for their dispersion were developed. Based on the selected modifiers, effective compositions of composite gypsum-containing materials based on local and secondary raw materials were developed. An increase in their strength and resistance to water was established. The use of gypsum plaster mixes shows their high efficiency and advantages compared to traditional finishing works methods. They provide a high and stable level of finishing quality, reduced transportation costs, and easy recycling of materials. However, despite the high consumer properties, the modern use of compositions based on the most affordable gypsum raw materials in the Republic and the production of gypsum binder beta calcium sulfate semi hydrate is limited to plasters and putties for rooms with normal operation. This is mainly because the compositions have a short setting time, low water resistance, and low strength characteristics. As a rule, the softening factor for such compositions does not exceed 0.5, and the compressive strength is 4-6 MPa
The stress-strain state of the universal chassis of the tractor trailer in T-Flex
Authors: Khakimzyanov Ruslan , Togaev Anvar , Rashidov Aziz
Published: June 2021

This article discusses the calculation of the strength of the frame structure of the universal chassis of the tractor trailer in the T-Flex software package and the comparative analysis of the results with experimental data and model data based on the principle of virtual work (possible movements).
Physicochemical method of fixing mobile sands with local materials
Authors: Muzaffarova Mauzhuda , Mirakhmedov Makhamadzhon
Published: June 2021

Impregnating composition with water-soluble binders has been elaborated, with the help of which the source of deflation of mobile sands is blocked, and the protective crust obtained on the sandy surface is characterized by resistance to the effects of wind-sand flow, assessed by plastic strength and thickness. The free-flow movement of a binder in a porous body of sand depends mainly on the equivalent diameter of the particles obtained by the joint solution of the internal and external problems of hydrodynamics and the shape factor of the particles. To interpret the experimental results empirically, an indicator of the saturation of the protective crust sand characterizing the impregnation as an unstable process proceeding under the predominant influence of the gravity field with an uneven movement of the liquid front was revealed. The prevalence of the elastic-plastic properties of the protective crust is evidenced by a slight and smooth change in physical and mechanical indicators over time by the third year of operation.
Stability of the embankment of fine sand reinforced with geosynthetic materials
Authors: Lesov Kuvandik , Kenjaliyev Mukhamedali , Mavlanov Akhmadjan , Tadjibaev Sherzod
Published: June 2021

This research paper validates the significance of an assimilated attitude when choosing the design of the subgrade of railways constructed from fine sands in difficult engineering and geological conditions in the desert and steppe territories of Uzbekistan to ensure their sustainability with modern technologies and materials. The analysis of the results obtained in the calculations of the stability coefficient of the design structure of the embankment. The characteristics of the embankment soils correspond to the design data of the object "Removal of the existing railway section Dunguluk-Burgutli-Misken from the flood zone of the Shurbulak reservoir" The results of the calculations performed by the method of G. M. Shakhunyants, as well as the software "GEO 5" and "Plaxis 2D" show that the structure of the embankment with a height of more than 6 meters does not provide the required standard coefficient of stability. Complete warps of the embankment and graphs of changes in the stability coefficient of the design structure of the embankment, and with the laying of geotextiles as reinforcement of the pattern of the subgrade of railways, are given. Beneficial solutions to increase the stability coefficient of the embankment from fine sands are proposed, and the efficiency of using geosynthetic materials as a reinforcement of the pattern of the subgrade is substantiated. Theoretical calculations and analysis of prevailing embankment structures confirm the feasibility of reinforcing the structure of the subgrade erected from fine sands on the railway lines of Uzbekistan.
Use of geo-information systems in the registration of road-traffic accidents on the roads
Authors: Yadgarov Sirojiddin , Muminov Qurbon , Ergashev Qaxramon , Sayfutdinova Ruzigul
Published: June 2021

We come up with the use of traditional methods in recording road traffic accidents that occur on highways, which makes the YTH analysis several difficulties and shortcomings. The analysis of YTH s has been shown to be effective in the use of Geoinformation systems. In conclusion, it can be noted that international experience shows that in recent years in European countries with well-developed motorization with high GDP and the level density of the road network, a national policy, and programs in the field of road safety in the medium and long term, in addition to the General problems and methods of their solutions, identifies targets, characterizing the level of road safety. This must include experience in implementing similar programs in other countries with a similar rate of car ownership, income level of the population, the condition, and development of the road network. The level of development of the road network, which is characterized by compliance with the total length, density, distribution of roads by functional value and categories, socio-economic needs of society in road transport, plays a significant role in the formation of accidents.
Transverse Vibrations of Underground Pipelines with Different Interaction Laws of Pipe with Surrounding Soils
Authors: Mardonov Batir , An Ekaterina , Shojalilov Shuhrat , Khakimova Yakutxon , Ismoilova Gulchexra
Published: June 2021

Studies on the effect of changing the stiffness coefficient along the length of the pipeline on its resonant vibration mode are considered in the paper. A computational model of transverse vibrations of the pipeline located in soil with different properties is created. Theoretical and computational studies to solve the problems of stability of underground pipelines located in the soils with different properties under seismic effects are carried out. It is revealed that the vibratory process of the pipeline can be realized at frequencies close to resonance. The results of the study are presented as curves of distribution of displacements of pipeline sections along the length at dimensionless frequencies. When the pipeline vibrates with a frequency close to the resonant frequency, the displacements of pipeline sections can take very large values. It is shown that at frequencies close to resonance, the values of moments can be large in the pipeline sections, which are the reasons for the loss of pipeline stability.
Slowing down the corrosion of metal structures using polymeric materials
Authors: Nurkulov Fayzulla , Ziyamukhamedova Umida , Rakhmatov Erkin , Nafasov Jasur
Published: June 2021

This article examines the resistance of corrosion-resistant polymeric materials to chemical reagents and the degree of corrosion, taking into account the direction of corrosion processes. One of the main factors that determined the corrosion rate is air humidity and dust released into the atmosphere during industrial emissions. Mixtures based on polymer materials can be used to gum up chemical apparatus and equipment; for corrosion protection, expensive materials are required. The sample is conditioned for 30 months at (23 ± 2) 0С, relative humidity (50 ± 5) %, and the thickness of the sample is determined. Resistance to chemical reagents the change in mass of samples of polymeric materials at a temperature of 35 0C for 3 months was analyzed. It was also found that by determining the corrosion rate (grade St3) by storing steel plates in a different exposure environment for 50 days. As a result, the corrosion rate of steel anti-corrosion coatings is lower than the control sample. According to the data obtained, it was found that the chloro-sulfonated polyethylene compositions are resistant to various organic solvents, acids, alkalis, oxidizing agents, and others.
Improving water resources management in the irrigated zone of the Aral Sea region
Authors: Matyakubov Bakhtiyar , Koshekov Rashit , Avlakulov Meili , Shakirov Bakhtiyar
Published: June 2021

One of the most important objectives in the world is to improve rational water resources management methods. In this regard, the rational management of water resources and optimal water resources distribution, especially on on-farm systems, are considered very important. In this direction, given the negative consequences that have developed over the past more than 40 years in the lower reaches of the Amu Darya River, the need to improve the methods of effective management of water resources in the Aral Sea basin is urgent.
Reconstruction of the closed horizontal drains in the Jizzakh region
Authors: Serikbaev Bakir , Sherov Anvar , Dustnazarova Sanobar , Muhammadeva Matluba , Gulamov Sardor
Published: June 2021

The article is devoted to the reconstruction of existing old drainage systems in order to radically improve the reclamation ecological and sanitary conditions of the lands of the Jizzakh region to improve the social conditions of the population and obtain high stable yields of cotton and other agricultural crops. As a result of many years of theoretical and irrigation to experimental research, operational monitoring in farms in the Pakhtakor district of Jizzakh region. The parameters of the primary horizontal drain are determined based on the analysis of reclamation climatic, soil, geological, hydrogeological, hydrological, economic, and other conditions. The calculation of the reconstruction of horizontal closed drainage is based on the method of A.N. Kostyakov in intensity from working the groundwater level after flushing. The depth of the drainage was determined, taking into account global climate change in recent years; based on these changes, an adjustment was made in the calculations to determine the value of the critical depths of groundwater during the operation of drainage systems. The incoming and outgoing parts of the water balance of the experimental plots were determined. In the presence of pressure groundwater, the size of the supply of groundwater with pressure water is determined. More proposed by the V.N. Shestakov's formula.
Resource-building structures hydraulic account for treatment of vehicle washing stations wastewater
Authors: Arifjanov Aybek , Umarov Uchqun , Abdullayev Akmal
Published: June 2021

The article presents a method for calculating the parameters of treatment facilities to bring the level of precipitation and wastewater from small enterprises, shops, and services of the Republic to the level of sewage and irrigation trays. The aim is to improve the design parameters of resource-efficient wastewater treatment plants and their widespread use, increase the production capacity of local wastewater treatment plants, improve the level of wastewater treatment and prevent environmental degradation. Hydraulic calculation of the design parameters of the settling tank was carried out at the local treatment plant. The precipitator works by precipitating suspended solids and separating petroleum products from the liquid surface. At the local treatment plant, the content of petroleum products in industrial and precipitation effluents was reduced to 3 mg/l, and the number of suspended solids to 1-1.5 mg/l.
The role of the irrigation network in the efficient use of water
Authors: Matyakubov Bakhtiyar , Yulchiyev Davronbek , Kodirov Isomiddin , Axmedjanova Gulnoroy
Published: June 2021

The article highlights the unique role of irrigation canals in the supply of water in the required amount, depending on crop demand and the rational use of it. The study of the prevention of filtration in irrigation networks and the study of the existing malfunctions in the operation of irrigation networks, the sequence of works on the repair of irrigation networks were analyzed, and the priority of repair work was determined. The current state of the Khumbuz canal in Khiva, Khorezm region of the Republic of Uzbekistan was studied. Information was obtained and analyzed on compliance with design specifications during construction and the presence of protection zones in the canal design. Analytical indicators have been developed to extend the service life of the Khumbuz canal to ensure its normal operation and supply the required amount of water to crops. In the implementation of water supply to agricultural crops, priority is given to the repair and construction of hydraulic structures, including the Khumbuz canal. In addition, all the work to be done was planned based on the priority of the work. It has been found that the amount of water required to irrigate crops can be achieved uniformly along the length of the canal, at the top, middle, and bottom of the canal, by ensuring that the irrigation networks operate at the required level. Specific scientific recommendations have been given for the normal operation of the Khumbuz canal. Repairing the canal has been shown to increase water use by 20 percent and increase crop yields by 15 percent by ensuring that crops receive the required amount of water on time. The service area of the Khumbuz canal is 1.460 hectares. The length of the canal to be repaired is 6 km. of which 2,568 km of new concrete. The maximum water flow of the canal is 2.5 m3/sec, and the normal water flow is 2.0 m3/sec. The efficiency of the channel (canal) is 0.93. The article provides information on how to achieve efficient use of irrigation water by repairing hydraulic structures at the required level and the construction of new ones.
Exploration of the hydraulic structure of the water supply facilities operation mode and flow
Authors: Khidirov Sanatjon , Oymatov Rustam , Norkulov Bakhodir , Musulmanov Furqat , Rayimova Iroda , Raimova Ikboloy
Published: June 2021

For multi-section drainage facilities, it is important to develop operational measures based on maneuvering moving barriers. Maneuvering of moving barriers is a measure that carries out the flow of water from the upper reaches to the lower reaches at the required level, taking into accounts the design features and operational mode of the hydraulic regime of the drainage structure. The maneuvering mode in the flow of water from the discharge structures ensures the order of opening, phasing, and level of opening of these movable barriers. Hydraulic conditions are associated with the effective control of the hydraulic regime in the lower part of the drainage structure or the suppression of excess kinetic energy, the reversal of the flow, or the prevention of post-riser deformation processes. Creating conditions ensuring that the hydrotechnical and hydropower construction of the water transfer or discharge facility is adapted for use in conjunction with a hydropower plant, water intake, sluices, and flow control system.
Geometric issues of transforming a topographic surface into a design project
Authors: Kuchkarova Dilarom , Achilova Dilnoza
Published: June 2021

Natural relief adjustment for functional purpose - the task of vertical planning - is one of the main complexes of engineering preparation problems of urban areas, industrial sites, reclamation of irrigated land. Numerous methods of designing vertical levelling are aimed at building algorithms that would allow us to obtain an optimal solution in an automated mode. In the set of problems of engineering preparation of urban areas and industrial sites, vertical planning is defined as:

a set of engineering and aesthetic measures aimed at adapting the natural relief for the needs of development and subsequent operation, taking into account the functional characteristics of the site

a part of engineering preparation, which consists in providing a height arrangement of buildings and structures necessary for the best technological connection between individual objects, as well as a quick collection of atmospheric waters

Reclamation of irrigated lands has specific requirements to design surface - maximum preservation of fertile layer, the satisfaction of cultivation technology conditions of different crops and irrigation technique. The main disadvantage of all known methods of designing vertical levelling is a cumbersome solution - a very labor-intensive way of successive approximation to an acceptable solution requires a large expenditure of computer time and subsequent manual revision. The article proposes one of the approaches to the design of levelling using geometric estimates.
Filtration reliability and safety of earth-fill dam
Authors: Khasanov Khojiakbar , Babajanov Kakhramon , Babajanova Nodira
Published: June 2021

The study of the reliability and safety of the constructed earth-fill dams and the comparison with their design and calculated data makes it possible to improve the structures and methods of the calculation substantiation of these structures. This work aims to study the filtration reliability and safety of the earth-fill dam of the Channel water reservoir of the Tuyamuyun hydroelectric complex (THC) on the Amu Darya River, which was put into exploitation in 1984. Field studies were carried out according to the traditional method using results of control and measuring equipment (CME) embedded in the body of the dam. The water levels of the upper and lower reaches, piezometers, and drainage water flow were measured. The maximum water levels upstream of 130.00 were observed in July-August and November 2017, and the minimum of 117.50 at the end of March. The water levels downstream depend on the value of the discharge through the hydrosystem. The maximum level downstream for 2017 was 112.55 m (01.06.2017) with a flow rate of 2000 m3/s. The minimum level downstream of 109.15 m was observed on November 29, 2017, when the discharge into the downstream through the hydroelectric complex was 260 m3/s. A tendency to an increase in the level of the bottom downstream was found. Filling and depletion graphs of the Channel water reservoir have been built, from which it is found that they reached 2.00 m/day, and 1.60 m/day, respectively. This is 4 and 1.6 times more than the standard 0.5 m/day and 1.0 m/day. Of the 53 piezometers, 34 are working conditions; the rest do not work, require flushing. Graphs of water level changes in piezometers show that they change with an average 15-20 day delay in the water level in the Channel water reservoir. In general, the natural depression curve is below the design one. The maximum filtration flow rate was 63.3 l/s at a water level in the upper pool of 129.00.
Photoelectric recorder for measuring deformations of buildings and hydraulic facilities
Authors: Zaxidov Nematjon , Shoyusupov Shoakbar , Pulatova Dilnoza , Rahmatillayev Shahzod , Gafurov Doniyor
Published: June 2021

The article discusses the issue of improving the accuracy and efficiency of geodetic measurements by scanning a laser beam into a plane and a photoelectric recorder of deviations from a given plane, in which a cZ-shaped photo recorder with three photosensors is used as a photosensor, combined at the output with three fiber-optic nodes and connected to an electronic circuit with three counters. A variant of using solar photovoltaic cells installed on the surface of a photoelectric recorder is proposed.
Consideration of climatic factors in the operating mode of hydraulic facilities in the Amudarya river basin
Authors: Kattakulov Farrukh , Artikbekova Fotima , Gafurov Zafar , Jumabaeva Gulnora , Musulmanov Furqat
Published: June 2021

This research is devoted to the analysis of the dynamics of climate change in the Amu Darya river basin using the global climate model and observational data. And also, the purpose of the study is to scale down and correct the offset of the GCF and adaptation to the Amu Darya river basin and assess the dynamic climate change and its future predictions of the impact on the hydraulic structures of the Amu Darya river basin. The offset correction was carried out on the basis of data from open sources from the archives of the world meteorological organizations and the analysis performed for the next 100 years. The article analyzes the results of the regions affected by the climate [1] from the point of view of the reduction of water resources, the disappearance of glaciers, an increase in temperature, and a decrease in precipitation. An increase in temperature leads to a steady decrease in the area of large glaciers, while small glaciers gradually completely disappear and a change in the ratio of solid and liquid precipitation alternately, which leads to a reduction in snow cover and is also accompanied by degradation and melting of snow cover permafrost in high mountain areas. For future projections of glacier area and melt water release, glacier volume is required. Climate change affects the hydrological regime of the river; this process worsens the operational regime of hydraulic structures in the Amu Darya basin. Such changes in glaciation, snow cover, and permafrost negatively affect the change in river flow and its distribution and the ecological assessment of the quality of the environment. Therefore, the study of changes in climatic conditions in the region and the development of climate change scenarios for the XXI century is carried out following the recommendations of the IPCC using the necessary programs.
Discussion of different Remote sensing satellite possibilities for scientifical Earth observations
Authors: Arifjanov Aybek , Akmalov Shamshodbek , Shodiev Shakhzod , Haitov Abdukarim
Published: June 2021

More than 1,000 satellites are launched into space, and they differ in their functions, rotation orbits, resolution, and other properties. Scientists divide the satellites into low-resolution, medium-resolution, high-resolution, and very high-resolution satellites by their properties. Now, the biggest challenge facing scientists is to use some of these different resolution images in their field. To get the expected result, it is very important to analyze the image that needs an which gives more accurate results. Therefore, the main attention of this article is aimed to find the answer to these problems. In this article 3 satellite images which have different resolution are analyzed. The possibility of middle-resolution images of MODIS, high-resolution images of Landsat, and very high-resolution images of WorldView-2 (WV-2) satellites using GIS are analyzed. A research area was the Syrdarya region, and downloaded different images of satellites of this area and compared with using e Cognition. According to the results, a more accurate satellite image for irrigation sets information is WorldView-2 images. In comparison analysis, it shows more accurate properties than other satellite images. As irrigation sets are small objects for the analysis, very high spatial resolution satellite images are important. Water discharge and surface change happen very fast; thus, it requires daily monitoring of the condition. And in this case, the temporal resolution of the MODIS and Landsat is 16 day, and it is a too long period.
Comparative tests of ridging cultivators with active and passive working tools
Authors: Panov Andrey , Mosyakov Maxim , Semichev Stepan , Plyaka Valery , Lylin Nikolay , Mekhedov Mikhail
Published: June 2021

Two types of ridging cultivators for growing potatoes and other vegetables were designed and tested. The first machine GPK-2 has active working tools – rotary drum with straight cutters, passive sweeps on rigid tines, and plates forming ridges. The second machine GD-2 has only passive drought working tools: spring S-shaped tines with sweeps of two forms, disks, and plates forming ridges. Field tests were carried out to determine soil preparation quality and energy consumption indicators of both machines on loamy soils typical for the non-chernozem zone of the Russian Federation. It is advisable to use the indicator of the specific power consumption related to the average diameter of loosened soil clods. Measured specific power per average clod diameter was in range 3.3…4.3 kW×mm−1 for the active rotary ridging cultivator, and 2.6…3.2 kW×mm−1 for the cultivator with passive working tools. The required power for the machine with passive working tools at the maximum possible forward speed is 25…35% lowers than for a rotary machine. Though cutting ridges on the post-planting treatment of loamy soil, rotary tiller supplies better soil crumbling. On inter-row cultivation of light loamy soils, the machine with passive working tools is a preferable solution due to less energy consumption relative to the machine with an active rotary drive.
Regulation of mains voltage and reactive power with the help of a synchronous compensator by two-axis excitation
Authors: Pirmatov Nurali , Bekishev Allabergen , Shernazarov Safar , Kurbanov Najmiddin , Norkulov Usmon
Published: June 2021

The article describes the design of a synchronous compensator with biaxial excitation and its automatic excitation control system. In addition, the issues of ensuring the required voltage level at fixed points using synchronous compensators with biaxial excitation were considered. In addition, the U-shaped characteristic of a synchronous generator with biaxial excitation was obtained.
Mini crusher-shredder for farms
Authors: Astanakulov Komil , Karshiev Fakhriddin , Gapparov Shokir , Khudaynazarov Dilshod , Azizov Shavkat
Published: June 2021

The purpose of the study is to substantiate the parameters of a mini crusher-shredder for processing coarse feed stalks in farms. The feasibility of using a mini crusher-shredder for processing coarse feed in the conditions of farms and farms with a small number of animals, which has a rotary-type shredder that combines the operations of grinding and crushing, is justified. The research uses the laws and rules of mathematical statistics, mathematical planning of experiments, and the methods given in existing regulatory documents. Experimental studies were carried out to study the influence of the rotor parameters of the mini crusher-shredder on its quality performance. A compact crusher-shredder has been developed, which has good visibility of the working bodies, high reliability, and quality of work due to zootechnical requirements. Experimental studies have established that when using a hammer of a flat-turned shape with a lower sharpening and a rotation angle of 60 or more, high-quality grinding of the stems is provided.
Taking into account the constraints in power system mode optimization by genetic algorithms
Authors: Gayibov Tulkin , Pulatov Behzod
Published: June 2021

Over the past decades, many publications on the use of genetic algorithms, which offer a new and powerful approach for solving the problem of power system mode optimization, have appeared. Despite this, the issues of effectively taking into account various constraints when solving such problems with genetic algorithms remain opened. In this regard, this article proposes an algorithm for optimizing power system modes by genetic algorithm, taking into account functional constraints in the form of equalities and inequalities by various penalty functions. The results of effectiveness research of the given algorithm in the example of optimization of 8-nodal power system with four thermal power plants and three lines with controlled power flows are presented.
Dynamics of the movement of the ripping tool for surface tillage
Authors: Abdurakhmonov Urol , Juraev Bakhodir
Published: June 2021

The study aims to analyze the stability of the movement of the ripper tool for surface tillage. The basic principles and methods of classical mechanics, mathematical analysis, and statistics were used in this study. The dynamics of the movement of a ripper tool for surface tillage are considered, depending on the forces acting on it and its design parameters. A computational dynamic model is developed, and an equation describing the angular oscillations of the longitudinal links of the parallelogram ripper mechanism is obtained. It is established that the uniformity of the depth of the cultivator depends on the amplitude and frequency changes of the components of the disturbing force, physical and mechanical properties of the soil, the moment of inertia of the Ripper, the length of the longitudinal links parallelogram mechanism, the forces of the pre-tension pressure springs, and its stiffness. It is established that the required uniformity of the depth of tillage can be achieved by selecting the pre-tension force of the pressure spring and its rigidity. Theoretical and experimental studies have established that the required uniformity of the processing depth with minimal energy consumption of the soil is provided with a pre-tension force of the pressure spring of the ripper attachment mechanism of 350 n, spring stiffness of 40 n / cm, and a speed of 2.0 m/s.
Traction resistance of a ripper with a current distribution line
Authors: Batirov Zafar , Sharipov Shuhrat , Mahmudov Yokubjon , Azizov Shakhboz , Mamadiyorov Obid
Published: June 2021

The pipeline distributor carries out deep loosening of the soil and three-tier fertilization. The study aims to determine the traction resistance of the working body of the ripper with a distribution pipe. The study uses the basic provisions of mathematics, theoretical mechanics, and agricultural mechanics. The method of calculating the traction resistance of the cultivator-fertilizer equipped with pipelines-distributors for three-tier fertilization is presented. The components of the balance of traction resistance are determined. Analytical dependencies are obtained for determining the traction resistance of the working body of the ripper with a distribution pipe. It has been established that the traction of the ripper working body with the fertilizer distributor depends on the physical and mechanical properties of the soil, the blade thickness and length of the chisel blade, the length of the working surface of the share, the angle of crumbling and the solution of the share, the width of the working body and the speed of movement. The traction resistance of the pipeline is 12-12.5% of the traction resistance of the rack and 4-5% of the total traction resistance of the ripper working body.
Technological process of uniform distribution of fertilizers over the width of the coulter
Authors: Batirov Zafar , Razzakov Tura , Begimkulov Fayzilla , Boymuratov Farrukh
Published: June 2021

The applied methods of applying fertilizers for cotton in Uzbekistan do not fully ensure the supply of nutrients to the plant's root system. The study aims to substantiate the technological process of uniform distribution of fertilizers in the root development zone and the parameters of coulters. When the fertilizer is distributed in the root development zone in tiers and the right ratio, the coefficient of their use increases, and the yield of cotton increases. The research uses the laws and rules of theoretical mechanics, mathematical statistics, mathematical planning of experiments, and the methods given in existing regulatory documents. The technology of forming new ridges instead of existing ridges and new furrows instead of existing furrows in fields with harvested husk with simultaneous fertilization and an improved chisel cultivator-fertilizer with comb-forming agents for its implementation, as well as the results of theoretical studies to substantiate the main parameters of the tuk coulter chisel-cultivator are presented.

The study determined the parameters of universal fertilizer Coulter chisel-cultivator of fertilizer: the base cone of the diffuser in the form of an ellipse with minor axis width 10 mm, height tool provider relative to the upper base of the truncated cone of 60 mm, and a diameter of a half-cylinder of 20 mm.
A method for cleaning tanks from oil product residues based on biotechnology
Authors: Hamroyev Obid , Ravshanova Nargiza , Jovliyev Vasik , Komiljonov Suxrob
Published: June 2021

The known methods of cleaning tanks from the remnants of petroleum products using existing means are quite time-consuming, energy-intensive, and insufficiently advanced. In addition, waste cleaning solutions are poorly regenerated and slowly oxidized in the biosphere, and their removal to landfills (or discharge into reservoirs) causes great harm to the environment. Therefore, the search for new methods of cleaning is a very urgent task. This work aims to develop a method for cleaning tanks from the residues of petroleum products based on biotechnology. This article proposes a technological scheme of an experimental installation that simulates a tank for storing petroleum products in agricultural conditions. Studies on the oxidation of petroleum product residues by selected active cultures of microbial strains have been carried out. The modes of biological cleaning of the internal surfaces of tanks for the storage of petroleum products, from their residues, are determined. Strains of oil-oxidizing microorganisms were used as biologics). The biomass of the studied microorganisms was obtained under laboratory conditions by deep cultivation in flasks on a mineral medium. The proposed method of tank cleaning is an environmentally friendly process, during which microorganisms decompose oil pollution at relatively low temperatures (20-40°C) and use hydrocarbons as a source for their growth. As a result of this process, many tons of oil deposits are converted into microbial cells, which in turn become a source of food for other organisms and the plant world.
Hydraulic energy storage of wind power plants
Authors: Urishev Bоboraim , Beytullayeva Rumiya , Umirov Аsror , Almardonov Оybek
Published: June 2021

The article discusses information on the need to accumulate energy from renewable sources to improve their efficiency, as well as some examples of the integration of systems for hydraulic energy storage and renewable sources, which ensure an increase in the reliability and volume of energy generation. The method for determining the parameters of a wind power plant's hydraulic energy storage system, which is based on the balance of the daily load produced and spent on energy storage, is presented. With changing daily loads, this technique makes it possible to determine the main parameters of the complex, including the volume of accumulated water, the coefficient of energy use of the wind power station. A functional diagram of the programmed control of the pumped storage and wind power plant parameters for the optimal use of the wind potential in hydraulic energy storage is presented. Based on the results of calculations using the proposed method, the main parameters of the system based on pumped storage and wind power plant with a capacity of 100 MW were determined, the efficiency of hydraulic energy storage was determined in comparison with lithium-ion batteries.
Optimization of daily operation mode of photovoltic systems of enterprises
Authors: Gayibov Tulkin , Abdullaev Elnur
Published: June 2021

At present, one of the most important issues at the level of various manufacturing enterprises is the development of ways for building and efficiently using renewable energy sources, especially solar energy. In this regard, this article proposes a mathematical model of the problem of determining the optimal daily mode of operation of a photovoltaic system in an enterprise with a private photovoltaic system connected to the electrical system. The effectiveness of the mathematical model was analyzed on the example of determining the optimal mode of operation of the photovoltaic system located on the territory of Jizzakh Polytechnic Institute. It is shown that the mathematical model can be used to determine the optimal operating modes of existing photovoltaic systems in enterprises and distribution networks, as well as to determine the optimal parameters in their design.
Mathematical modeling of the technological process of operation and parameters of the device for formation of longitudinal rollers (pawls) between cotton rows
Authors: Olimov Khamid , Khasanov Ibrohim , Imomov Shavkat
Published: June 2021

This article reveals the features of mathematical modeling of the technological process of work and the parameters of the device for the formation of longitudinal pawls between cotton rows. And also, the results of the STUDY are presented, and the following main conclusions were made: the task of mechanizing the formation of longitudinal legs can be solved by lifting the soil from the two side furrows and throwing it into the central furrow using a palletizing device with active working organs. Studies have shown that for the qualitative formation of longitudinal dogs between rows of cotton, it is advisable to use a device with a single-pass continuous auger. To avoid damage to cotton seedlings, to ensure the required productivity with minimal energy consumption, the screw device must have the following parameters: the screw diameter is 400 mm, the inner and outer diameters of the screw pipe 420 and 426 mm; respectively, the pitch of the screw is 320 mm; the rotation speed of not less than 325 rpm; and the mounting angle relative to horizontal-not more than 35 °; the entry angle into the ground shield located in front of the screw tube, the device needs to be within 24-25º.
Device for automation of hydrostatic leveling of man-made structures with alternative power supply
Authors: Zaxidov Nematjon , Shoyusupov Shoakbar , Rahmatillayev Shahzod , Jamolov Tulqin , Gafurov Doniyor
Published: June 2021

The article discusses the issue of ensuring the reliability, durability, and safety of buildings and engineering, including hydraulic structures, by creating an automated hydrostatic leveling system with a device that uses fiber optics combined with an LED and a photodetector, installed on one hollow axis of rotation of the drum, like a sensor a ferromagnetic transducer was used for the displacement pulse, a comparative analysis of the existing means for measuring settlements and deformations of objects using laser and photoelectric means was carried out. A patented device has been developed that provides high accuracy, reliability, and the ability to create a monitoring system with remote information delivery with an autonomous energy source. The device can be used to install and assembly conveyor lines in determining the vertical deformations of dams, buildings, and structures during operation.
Wear issues of pumping units
Authors: Ishnazarov Oybek , Isakov Abdusaid , Islomov Utkir , Xoliyorov Umirzoq , Ochilov Dilshod
Published: June 2021

The article presents the possibility of increasing the service life of pumping units. Particular attention is paid to the regulation of the speed of rotation of the pumping unit. There are some assumptions in the mathematical model that do not affect the final result. The factors influencing the operating mode are given. It is indicated that the speed of rotation of the pump shaft significantly affects the wear resistance of the pump blades. Thus, the regulation of the pump rotation speed will rationally increase its service life.