bluuebunny/crossref_metadata_2025 huggingface dataset:
Operation damless intake of the Amudarya river (Central Asia)
Authors: Atykbekova F , Uljaev F , Jumaboeva G , Gayur A , Ishankulov Z , Jumanov O
Published: July 2020

The article describes the nature of the ongoing channel processes occurring in large damless water intakes from the Amudarya-Karakum, Karshi, and Amu – Bukhara channels located in its middle course. The characteristic features of the ongoing channel processes in the area of water intake are given. Based on the analysis of the current state of damless water intake, a method for improving its operation is recommended. To solve the problems of ensuring high-quality water intake and water supply, experimental studies were carried out to determine the angle of the bottom threshold in the inlet section of the head structure in the ABMCh. The analysis of the studies showed that for the threshold angles to the shore β = 30°, 45° 60°, an increase in the angle β from 30° to 60° increases the intensity of the artificial transverse circulation formed in the flow. It is proved that this circumstance is also true for a constant angle of threshold β with an increase in the relative threshold height H

rth
. The bottom threshold ensures the entry of bottom sediments into the head structure of the damless water intake. The threshold height is set to 1.44 m, which is determined in comparison with the height of the beds of sediments. To prevent the entry of a large amount of bottom sediment into the head structure of a damless intake, it is recommended that the device be used especially in the inlet section of the channel. It is shown that a Karakum channel is intensively exposed to deigish. Moreover, in this process a certain sequence is traced. First, one deigish is formed, the erosion products of which create favorable conditions for the occurrence of the next deigish. So the chain of deigish “walks” along the shore. The distance between deigish, also a “step,” varies widely: from 3-7 to 15-40 m or more. Then, the remaining protrusions between the deigish are washed out, which leads to a general expansion of the channel. It has been established that deigish appears and develops in both straight and curved sections of the channel. In the latter case, they are formed mainly on the concave bank, although there are cases of their location on the convex. This means that there are corresponding conditions for its formation in both straight and curved sections of the channel. It is substantiated that the formation and intensive development of deigish are associated with the intense channel-forming activity of the flow, which manifests itself both in the process of developing channel forms and in active sediment transport. It is recommended that in order to prevent the deigish process, it is necessary to carry out water management measures aimed at strengthening the channel of the channel. The implementation of concrete cladding using modern materials to reduce losses on filtering the channel in addition to preventing deigish channel and also helps to increase the efficiency of the irrigation channel.
Forms of natural vibrations of a gravitational dam on an elastic foundation, taking into account the attached mass of water
Authors: Bestuzheva A , Kulyabin G
Published: July 2020

Based on the results of the analysis, we have constructed forms of the dam’s vibration forms on different bases, with or without taking into account the reservoir water. The main vibration tone of the 100-meter section of the gravity dam is in the cross direction (along the target) and varies from 0.929 sec to 0.635 sec. depending on the hardness of the base. The main tone of horizontal vibrations varies from 0.687 sec to 0.351 sec. The attached mass of water increases the period of horizontal vibrations of the dam from 0.380 sec to 0.474 sec. Also, we have defined 3 types of vibrations: “pure”, “pure shift”, “invisible form”. We confirmed the need to take into account the water body in solving the contact problem of joint vibrations of the structure with the base and reservoir to obtain real forms of natural vibrations of the structure and improve the accuracy of calculations of seismic resistance of structures in the framework of the linear-spectral theory.
Hydrodynamic pressure upon elements of the shutter with flexible working bodies
Authors: Kadirova M-G
Published: July 2020

For automatic control of the water level in the part of the channel in front of the hydraulic structure, a hydraulic automatic water level controller was proposed. Its main element is a shutter with flexible working elements, consisting of a reservoir formed by a shield for draining water from the channel and flexible cloth. To ensure stable operation without vibration, experimental studies of this shutter with a spillway in the form of a non-vacuum profile were carried out. These studies were carried out by the method of physical modeling of the model and nature in an experimental setup. The aim of the study was to determine the hydrodynamic pressure acting on this shutter, the forces of hydrodynamic pressure, and the centers of application of these forces to the shutter in the form of a non-vacuum profile. Studies have shown positive hydrodynamic pressure on the spillway of the shutter, the absence of vibration, the stability of the shutter. The obtained dependences for determining the forces and centers of application of hydrodynamic pressure forces to the elements of the spillway part of the shutter allow us to calculate this shutter
Simulation of spreading of non-conservative passive substances in water bodies
Authors: Krutov A , Norkulov B , Mavlyanova D
Published: July 2020

Numerical modeling has become an indispensable tool for solving various physical problems. In this context, two fundamentally different approaches to the derivation of equations describing the motion of a liquid and the transfer of both conservative and non-conservative substances that have or do not affect the flow structure. In addition to the classical approach, in which the hydrodynamic equations of the baroclinic fluid are obtained from the Reynolds equations by introducing the assumption that the turbulent viscosity between jets is neglected, there is another approach, which is to introduce a certain scale of consideration, as well as the use of hypotheses about the magnitude of turbulent viscosity and small changes of flow characteristics along with horizontal coordinates as compared with the changes along with vertical one. Thus, there is the option to obtain similar equations allowing to numerically simulating unsteady flows with fixed boundary conditions (fluctuating streams). Also, the article discusses an approach to numerical simulation of biogenic substances as well as the chemical and biological processes in reservoirs.
Advantages of solving the problem of turbine abrasion in the Burjar hydroelectric station by designing a sump
Authors: Badalov A , Kattakulov F , Buvabekov B , Kurbonova U , Abdukhalilov A , Rajabov M
Published: July 2020

Existing methods are considered for designing sedimentation tanks in the Burjar hydroelectric power station to solve the problem of abrasive wear of aggregates. Weighted sediments abrade the lining of derivational and station water conduits, as well as the working elements of hydraulic turbines. In the Burjar hydroelectric power station, there is a problem associated with the abrasive wear of the units. Abrasive wear of turbines leads to a significant drop in their efficiency, and therefore, a decrease in the power and energy generation of a hydroelectric power station, a reduction in the service life of hydroturbine equipment, and a fragment of wear. For the design of the sump, geological and hydrological information was collected about the Burjar hydroelectric power station. The sump is projected onto the derivation channel of the Burjar hydroelectric station. To determine the size of the sump, laboratory analysis of the water of the Burjar hydroelectric station was carried out. The hydraulic calculation of the sump includes determining the main dimensions of the chamber, sediment volume, flushing turbidity, and siltation time of the dead chamber volume with sediment. The calculation is described by the method of academician E.A. Zamarin. According to the method of E.A. Zamarin, the width of the chamber is 9.6 m and the length of the chamber is 73 m. These results are accurate and they were used during the design of the sump.
Calculation of sediment flow in channels taking into account passing and counter wind waves
Authors: Yangiev A , Eshev S , Panjiev Sh , Rakhimov A
Published: July 2020

The article discusses the process of sediment transport in channels under the influence of wind waves on the course. Based on the calculation method Quick M.C. dependences are proposed for calculating sediment transport in channels when waves are superimposed on associated and counter-current flows. The movement of sediments caused by the combined action of waves and currents is studied. It is shown that the direction of the movement of sediments is determined mainly by the direction of wave propagation (even in the case of a counter-current). Here the consumption of sediments is proportional to the power of the “wave flow” system. Comparing the results of the calculation with the dependencies of other authors gives satisfactory results.
A Numerical Model for the Temperature Regime of a Concrete Gravity Dam in the Climatic Conditions of Northern Vietnam
Authors: Aniskin N , Nguyen T
Published: July 2020

One of the main impacts on concrete gravity dams is the temperature factor. The effect of temperature factor on concrete dams will create additional deformation and stress, which can lead to tensile stresses and so gives rise to the thermal cracking. So, forecasting the thermal regime and thermal stress state in concrete gravity dams is a difficult task because taking into account a large number of influencing factors. This paper presents numerical modeling results on the temperature regime of the Banmong (Son La Province, Vietnam) concrete gravity dam with a height of 45m. The model has created by the MIDAS software package and can assess the influence of temperature factors on the dam structure during construction and operation period. The results obtained may be used when designing and making appropriate recommendations.
Technology to restore design parameters of irrigation pump discharge pipelines
Authors: Khudaev I , Muratov O , Turdibekov I , Yusupov M
Published: July 2020

The article discusses the restoration of irrigation pump station discharge pipelines’ design parameters, based on sand-cement anticorrosion shotcrete coating technology. Repair of created cracks, damages during operation, and restoration of design parameters of discharge pipelines is performed using shotcreting with Kalmatron® (USA) additive. Besides, paper theoretically validates optimal design data of restored discharge pipelines, the thickness of the anticorrosion coating, and their influence on working characteristics of irrigation pump stations. Theoretical and applied tasks are resolved based on the practical implementation of foreign technology, local supplies, and the use of the Company’s standards at water facilities throughout Uzbekistan’s irrigation systems developed and implemented by the authors of this article.
Method designing of open drainages
Authors: Fatxulloyev A , Abduraimova D , Otakhonov M , Atakulov D , Samiev L
Published: July 2020

During the construction of open drainages, to achieve economic efficiency, it is very important an accurate assessment of their parameters and projection size. The article is devoted to the creation of a mathematical model by taking into account the variability of flow movement and discharge rate in open drainages. The appearance of a mode of uneven movement as a result of the influx of infiltration water from the sown area to the drainage is described. Recommendations are given for determining the hydraulic parameters of drains. To study the movement of water flow in open drainage, the results of studies in the Boevut drainage system of the Syrdarya region are disclosed. The results of the analysis of the studies are presented. Based on the analysis results, a method for designing open drainages is proposed. The hydraulic parameters of the constructed new open drainage are determined in field conditions. The data determined in the field conditions are compared with the values of the proposed design method. Based on the comparison results, the reliability of the proposed design method was evaluated.
The role of inspection of hydraulic structures in the assessment of their technical condition
Authors: Kozlov D , Yurchenko A
Published: July 2020

The development of the territory of Moscow has led to the need for a survey of water bodies and inventory of existing hydraulic structures, a thorough assessment of their technical condition, typifying the main types of structures, and determining their functional features. To solve these tasks, we used methods of field expedition survey, and analytical calculations of hydraulic structures, statistical methods of information processing, and analysis of available cartographic and technical documentation. A quantitative and qualitative analysis of the state of hydraulic structures located on the territory of New Moscow and their operating conditions was performed; the current level of their safety was assessed. It is proved that it is necessary to create a unified information database for all water bodies and hydraulic structures that have passed the survey, as well as to develop a simplified form of the act of pre-Declaration inspection of structures for which there is no functional and design information. It is shown that it is necessary to develop a plan of measures to ensure the safety of hydraulic structures without registered property rights.
Determination of rational areas of irrigated plots in saline and subjected lands to irrigation erosion
Authors: Avezbayev S , Khuzhakeldiev K , Umarova F , Sharipov S
Published: July 2020

The article considers the issues of determining the rational plots of irrigated plots on lands inhabited and subjected to irrigation erosion. Rational areas of irrigated plots are determined based on the optimal aspect ratio of the irrigated plots, the degree of salinity of soils, the slope of the irrigated surface, and the flow rate of water in irrigated furrows. The optimal combination of irrigators and drains, which are the boundaries of irrigated plots and optimal distances between drains, were also taken into account. Recommended rational areas are defined for slightly, medium, and highly saline, as well as lands subject to irrigation erosion.
Hydromechanical Method of Soil Compaction
Authors: Vafoeva O
Published: July 2020

One of the effective methods for improving the physical and mechanical properties of soils of the foundations of structures is their compaction. The correct implementation of the compaction process significantly increases the bearing capacity of the foundation, evenly distributes the loads from the structures to the foundation, ensuring the stability of the upper and lower prisms of soil dams, reduces water seepage through the body of dams, increases the likelihood of maintaining the structure of compacted soils under the action of dynamic and seismic loads. For soil compaction, static, dynamic, and vibrational methods are used. These methods have a great effect when soil moisture is reached to range within 16 to 18%. Basically, various roller designs are used in soil compaction of earth structures. A review of existing soil compaction machines is given. The disadvantages of the existing soil compaction machines are their massiveness (roller mass up to 40t), the number of passes in one place (three or four), high consumption when watering the soil surface, and waiting for dry-up after watering each soil layer. The article recommends new designs of soil compaction, which eliminates the disadvantages of existing machines, namely: roller is reduced by 50-60%, water consumption is reduced two times, and the number of passes is reduced to one pass.
Dynamics of bioclimatic potential of agricultural formations of Almaty region
Authors: Sapaev I , Akhmetov K , Serikbayev A , Sapaev B
Published: July 2020

The article has the new technique and formula for determining the dynamics of assessment of the bioclimatic potential of climatic zones. Empirical models of potentially possible grain yield of cultures of the agricultural organizations of the Almaty region were also developed. The data on changes in temperature and precipitation received from metrological stations of the region on Hydrometeorology and environmental monitoring, as well as data from the website of the world meteorological network for 1998-2017, which reflect changes in atmospheric circulation observed in the last twenty years are analyzed.
Mechanized sowing of seeds of desert fodder plants
Authors: Farmonov E , Ismailova Z , Abdilaev T , Farmonova F
Published: July 2020

In the paper, the authors addressed the fact that the continuous improvement of pastures by mechanized sowing and undersowing of local shrubs, sub-shrubs, and perennial grasses is one of the main conditions to maintain the fodder productivity and to combat pasture degradation. This will increase the pasture productivity up to 10 times, compared with natural fodder land. The seeders have been developed with new pick-up drums equipped with measuring grooves, which, during operation, significantly reduce the crushing of seeds, ensure uniform high-quality sowing, do not lead to a decrease in their natural germination. Sowing is carried out following agricultural requirements. The parameters of a pick-up drum with measuring grooves are determined.
Choice of optimum extinguishers parameters for a dissipative mechanical system
Authors: Mirsaidov M , Teshaev M , Ablokulov Sh , Rayimov D
Published: July 2020

This article provides a detailed analysis of the problem of the optimal choice of parameters of dynamic dampers with two degrees of freedom. The choice method is based on calculating the difference between the resonant frequency of the system without absorbers and the nearest resonant frequency of the system with absorbers. The optimal parameters are determined and the effectiveness of many mass-dynamic vibration dampers with various types of viscosity under vibrational impacts is estimated. It has been shown that frequency-independent friction equally affects how viscous friction affects the behavior of the protected structure and damper and its effectiveness. A sufficient condition for damping vibrations in both coordinates is the presence of two dampers for movement, installed at different points. Frequency limits are set to suppress damping simultaneously in the upper and lower surroundings with respect to the resonant frequency of the main system, and also only in the upper neighborhood. It was found that the use of more than two absorbers while maintaining their total mass affects the frequency band in which it is possible to dampen the oscillations of the system.
General characteristics of networks and features of electricity consumers in rural areas
Authors: Rakhmonov I , Berdishev A , Khusanov B , Khaliknazarov U , Utegenov U
Published: July 2020

In addition to the reliability of power supply quality of electricity consumers are one of the most important characteristics of the electrical systems. It has a significant impact on the efficiency of electrical receivers and the technical and economic performance electric networks. In the modern developed networks providing quality indicators of energy acceptable for consumers, requires significant cost of funds and materials, as well as the collection and processing of more information. This explains the importance of the questions of power quality in the complex problem of the design and operation of electrical systems. If the provision in the electrical systems normalized values of the frequency is mainly due to the balance of active capacity and characteristics of the appropriate equipment on the electrical stations, the quality of the voltage at the consumer is determined mainly by cost distribution networks. For consumer’s rural areas referred to the costs are most of the total production costs and electricity transmission, so questions quality assurance voltage networks always were in the focus of research, design, and operational organizations. Particular attention these questions acquire at present in connection with the rapid growth of electricity consumption in agriculture and the relevant development of rural networks. The huge positive effect electrification to fully manifest only when consumers are delivered electricity is quite high quality. Reduction of the quality of significantly impairs performance electrical receivers and leads to marked electro receivers damage.
Development of standard cable cross-sections of rural electrical networks
Authors: Taslimov A , Melikuziev M , Matchonov O , Ruzinazarov M , Nasirov M
Published: July 2020

For the optimal development of electric networks, not only the optimal choice of the network element parameter from the existing standard scale (parametric series) of sizes is important, but also the optimization of standard scales of equipment sizes or checking their optimality. The method of economic intervals explores the existing parametric series of standard cross-sections of 10 kV cable cores and establishes that the existing series does not satisfy the conditions for optimizing the use of cable lines in rural areas. Since cable lines have not yet found wide distribution in rural areas, there are conditions not only to verify the optimality of the existing scale of cable conductor cross-sections but also to establish an optimal scale of 10 kV cable conductor cross-sections, intended for the construction of cable power transmission lines in rural areas (if the existing scale does not meet optimality conditions). For rural distribution electric networks, the initial and final sections in a parametric series (25 and 120 mm2) are determined and the optimal for rural areas parametric series of cable cross-sections of 10 kV (25; 50; 120 mm2) is recommended.
Mobile power supply for drip irrigation systems
Authors: Rajabov A , Bokiev A , Nuralieva N , Sultonov S
Published: July 2020

The widespread introduction of drip irrigation systems in Uzbekistan requires sufficient and guaranteed electricity supply to farms.

The purpose of the research is to substantiate mobile methods of the power supply based on renewable energy sources when implementing drip irrigation systems in the Republic of Uzbekistan. These goals can be achieved by applying modern methods of selecting the optimal design and energy parameters of mobile solar and wind stations. A systematic approach to the analysis of a complex power supply scheme is selected. The main provisions of theoretical electrical engineering and mathematical statistics are used in the study of processes in the power supply system using RES.

The calculations carried out to determine the daily, seasonal and annual schedules of electricity consumption showed that for mobile power supply, it is necessary to take into account such factors as specific modes of work that depend on agricultural requirements and seasonality. A prototype of a mobile power plant “sun-wind” is proposed, which produces 4.5 – 4.7 kWh in the daytime and 0.8-1.0 kWh in the evening.

It is required to develop a system of measures for the implementation of mobile power plants “Sun-wind” providing for the creation of appropriate service, training of service personnel, etc. This, in turn, increases the level of reliability and efficiency of power supply, creates favorable conditions for the widespread introduction of modern resource-saving electrical technologies in remote areas.
The resistance to pulling the working part where the manure juice is poured locally
Authors: Khudayarov B , Kuziev U , Sarimsakov B , Khudaykulov R
Published: July 2020

The object of the research consists of the architecture of the root system of intensive garden soil and trees, the process of interaction of the aggregate and its working part with the soil and roots, which pour the fertilizer juice locally. The only way to grow ecologically clean products from the garden is to feed the fruit trees locally with manure juice. In intensive gardens, it is advisable to pour the manure juice into the zone of branching tree roots 0.8–0.1 m long, 20–30 sm deep, and an average width of 15 sm. In the process of cutting the soil and roots of the working part of the fertilizer juice pouring unit, the force of gravity is formed. A dynamometer was used to determine the force required to cut the roots. To do this, it was dag a hole of 80 sm long, 30 sm deep and 15 sm wide along the row, without damaging the roots, leaving a distance of 20 sm directly from the trunk of the tree in the garden. The soil-cleaned roots were pulled into a dynamometer loop, pulled until they broke, and the breaking force was determined. For gardens, pouring sap on average 1 m long, 25-30 sm deep and 12-15 sm wide, leaving a protection zone of 20-25 sm from the trunk, increases the efficiency of fertilizer use. In the local method, the gravitational resistance of the working part, which pours the juice to depth, is on average 3.5 kN.
The new production of electrotechnology cottonseed oil and energy efficiency rating
Authors: Turdiboyev A , Akbarov D
Published: July 2020

Oil and fat products in food mix clusters, especially from technical seeds; cotton oil which has a specific character is one of the most important products for our domestic needs. Demand for oil and fat products, the growing demand of the population, and corporate foodstuffs to meet the growing population of the country. The article deals with the issues of increasing energy efficiency in obtaining oil from cotton seeds. The relationship between the amount of oil obtained and the degree of damage to cotton seed pulp is shown. Electropulse treatment of cotton seeds is expected to increase the amount of oil produced and to reduce energy costs in the technological process. As a result of applying the proposed technology, the process of pressing and squeezing oil from cottonseed seeds, reducing the duration of the frying of seeds, in turn, makes it possible to reduce the extracted technical oil.
Electric pulse treatment of organic waste before anaerobic fermentation
Authors: Muratov H , Imomova N , Ergashev Z , Sultonov M
Published: July 2020

One of the promising areas of processing organic waste from agriculture is through methane fermentation in biogas plants. They have important advantages over other methods of processing organic waste. Based on these problems, the article describes a method of processing organic waste under anaerobic conditions using electric pulse treatment of organic waste before loading into a biogas plant. The parameters of the production process of the bioenergy plant had the following values: humidity of organic waste 88-94%; the pressure of the gas phase in the bioreactor -2-3 kPa; the dose of daily updating of the mass volume in the bioreactor is 10% / day; the duration of one cycle of mixing 10 min; the frequency of daily mixing 17 days−1. Based on the equation, taking into account the listed optimal values of the factors, the biogas yield per 1 kg of OM was calculated and 0.146 m3 of BG/kg of OM was obtained. Laboratory and production results are given, as well as a comparison of the data obtained.
Advanced machine for sorting potatoes tubers
Authors: Bahadirov G , Sultanov T , Umarov B , Bakhadirov K
Published: July 2020

The article provided the results of studies to improve the design of a machine for potato sorting, the working surface of which consists of belts at different speeds. The aim of the work is to increase the accuracy of potato sorting according to their external dimensions, without damage. Using theoretical, one-factor, and multi-factor experiments and experiments in production conditions, the following optimal parameters of the improved patented machine for sorting potato were established: - the speed of a slow-moving belt of 0.4 m/s; - the speed of a fast-moving belt 0.6 m/s; - the angle between adjacent belts 0.46′26.

With these values of the factors, the accuracy of the criteria of the sorting machine is 95%.

An experimental model of the machine tested on the fields of farms of the Ferghana region of the Republic of Uzbekistan.

In the process of potato sorting, it was revealed that the indicator of damage to potato in the course of the experiments did not exceed 0.5%. It was found that to achieve 95% accuracy of sorting, at a feed speed of potato heap onto the belt surface of the machine 4.5 kg per second, the angle between the belts should be 0.46′26, the speed of the slow-moving belt should be 0.4 m/s and the speed of the second should be 0.6 m/s.
Mathematical model of oscillations of a railway tank car with partial fillingunder shunting collision
Authors: Bespalko S , Grigoriev P , Ibodulloev Sh , Turajonov K , Numonov A
Published: July 2020

This article is devoted to simulating longitudinal vibrations of the tank car in case of partial filling with liquid during shunting collision. A brief overview of studies of the movement of solid bodies with liquid was performed. The design scheme of cars, represented by a 4-mass system with elastically-dissipative connections, has been developed. A system of differential equations of car motion according to the main equation of dynamics has been compiled. The mathematical model of liquid cargo oscillations based on shallow water theory is derived. In integration, the characteristic method and Euler method are applied. It is envisaged to transfer parameters between the mathematical model of cars (tank acceleration) and the mathematical model of liquid load (pressure forces on the bottoms). The methodology is implemented in the C++ Builder programming environment. According to the developed method, a study of the shunting collision with the tank at incomplete filling was carried out. The dependence of the reaction in the automatic coupling on time has two bursts. The maximum reaction is also dependent on the impact rate and the degree of filling of the tank.
Selection of electrode materials for membrane less fuel cells based on immiscible liquids
Authors: Tarantseva K , Yakhkind M , Politaeva N , Tarantsev K , Korosteleva A , Emurlaeva E
Published: July 2020

The possibility of using various materials as electrodes for membraneless fuel cells based on immiscible liquids, both from the standpoint of the thermodynamic possibility of the process and from the point of view of their corrosion resistance, is considered. The corrosion resistance of materials from alloys based on iron, as well as carbon was investigated for use as electrodes in membraneless fuel cells based on immiscible liquids. The possibility of using them instead of electrodes based on ruthenium and platinum in the studied alkaline aqueous ethanol system was shown. It was found that the highest electromotive force in the system occurs when using an activated carbon anode in the top ethanol phase and a carbon steel 10 cathodes in the bottom aqueous phase. The possibility of using activated carbon instead of a ruthenium-coated titanium electrode and platinum-coated titanium electrode, at almost equal exchange currents, will significantly reduce the cost of manufacturing a fuel cell. Thus under certain conditions, this type of fuel cell can compete with membrane fuel cells that have received industrial implementation
Stabilization of mechanical system with holonomic servo constraints
Authors: Khusanov K
Published: July 2020

The proposed study is devoted to the derivation of the equation of disturbed motion of mechanical systems with releasing servoconstraints, in which the multipliers of the normal and tangential components of the servoconstraints reaction forces are taken as control parameters. A technique is proposed for determining the reaction forces of servoconstraints providing motion stabilization relative to the manifold determined by holonomic servoconstraints. As an example, the problem of a gyroscope in a gimbal mount with holonomic releasing servoconstraints is considered.
Research on Biparametric Resonant Displacement Sensors Deviation
Authors: Sanbetova A , Sulliev A , Kasimov Sh
Published: July 2020

BPRS displacement and its characteristics showed that the possible causes of deviations are imperfections of the method, operating principle, manufacturing inaccuracy, the volatility voltage amplitude of the power source, its form, and frequency, as well as other adverse external conditions.

The most important characteristic of biparametric resonance sensors (BPRS) of displacement, like any measuring transducer, is its deviation [1].

In this work, the deviation of the BPRS movement was estimated by the method of parametric structural schemes (PSS) [3]. The advantage of this method is the ability to analyze deviation that is invariant from the physical nature of the phenomena occurring within the sensors. Besides, this method is visual and convenient when compiling deviation equations that take into account all their types.

The PSS of the developed BPRS displacement taking into account possible sources of deviations is shown in Figure 1.

In view of the systematic and random component of the deviation of each elementary transformation according to PSS, it is allowed to write the following system of equations for the right section of the BPRS:
Parameters and indicators of the longitudinal-transverse oscillation sieve
Authors: Astanakulov K
Published: July 2020

The work quality of the grain cleaning machines depends on work indicators of the sieve. Based on this, longitudinal-transverse oscillation sieve developed for grain cleaning machine. The developed sieve researched theoretically and experimentally. According to the researches, it was defined that the longitudinal oscillation of the grain-cleaning sieve n

fr
= 140 – 175 rpm, the amplitude of the longitudinal oscillations A

l
= 30 mm, the amplitude of the transverse oscillations A

t
= 3 – 5 mm, and the slope angle α

s
=14°. In these operating parameters work indicators of the sieve consisted of the grain losses is not more than 0.5 % and cleaning efficiency is 99.6 %. It found that the quality indicators of the longitudinal-transverse oscillation sieve on the same loads are 1.2 – 2.3 times higher than the longitudinal oscillation sieve.
Electrotechnological treatment against diseases found in almond trees grown in arid lands
Authors: Baizakov T , Bozorov E , Yunusov R , Yusupov Sh
Published: July 2020

This article explains the main diseases of horticulture trees and almonds, grown on the slopes of the hills. Currently, the protection of the environment, especially the protection of land and water resources from the effects of various toxic substances, is one of the main problems of world civilization. During the financial and economic crisis in the world, the Republic of our country is currently using high-quality land resources, introducing advanced scientific and technical agricultural technologies, producing low-quality and high-quality crops. One of the important problems. Management and control of the use of the land Fund, improvement of land relations, and effective use of public land in General. Application of electrical techniques for growing almonds, pistachios, nuts, and fruit-bearing products in the foothills. The root system of almonds clings to fungal diseases, that is. nematodes. When nematodes swell and become inflamed in the passages of tubers, they destroy the tree, especially young seedlings. We offer electrotechnical treatment for the treatment of nematode diseases of almond roots and get the results of electrotechnical experiments. To get the results of this experiment faster, we get the results by comparing photon measurements with the remote infrared spectrum. The use of electrical techniques for growing almond trees and fighting nematode diseases caused by its roots is considered, and the results of preliminary research are presented. It also provides a brief overview of the use and control of photogeometric methods.
Computer modeling the moldboards’ surface in autocad system
Authors: Juraev T
Published: July 2020

There are considered the tasks of the computer modeling of moldboard’s working surface in the article. The proposed solution was developed by geometric and computer modeling of moldboard’s working surface elements. As surface elements were chosen the frontal contour, a directory curve, and the generative lines with their pre-set conditions, which were given by specialists. The geometric models of working surface elements, which were developed based on research results were implemented in the AutoCAD system. The researches were carried out using the constructive geometric modeling methods and systems and based to surface modeling methods of Descriptive Geometry and traditional methodology of designing the moldboards. The proposed models, algorithms, and methodology can reduce the design period, simplify the geometric parameters setting, and facilitate the work of designers. The solution is required in educational, research, and production processes in Agriculture Engineering and can be used in developing other technical objects with geometrically complex surfaces.
Methods founding construction and parameters of longitudinal screw pawl-creating device
Authors: Olimov K , Juraev A , Ochilov M
Published: July 2020

This article outlines the results of the theoretical research based on the parameters of the working organs of the parameters of the construction of longitudinal pawl-creating device between cotton rows.
Mathematical simulation of transfer mechanisms of crocheting potato harvesting machine
Authors: Matmurodov F , Dustkulov A , Abdiyev N
Published: July 2020

The article proposes a new basic scheme of a potato harvesting machine, with many times the separation of graff impurities from potato tubers composition. The transmission mechanisms of the newly developed crocheting potato harvesting machine are mathematically simulated. This model will help the potato harvesting machine developers to determine the required dimensional and dynamic parameters, which are necessary for the development of new machine design. The proposed concept to a certain extent separates the impurities of a heap of potato tubers. Separating devices and improved separator-elevator mechanisms will help to better separate the soil lumps and stone from potato tubers. The mathematical model created by the driving mechanisms of the potato harvester allows you to find the values of the movement on the corresponding working mechanisms. This model will help the developers of the potato harvester to determine the desired dimensional and dynamic parameters that are necessary to develop a new machine design.
Low-power solar stations on dam surfaces of reserrvoirs
Authors: Denmuhammadiev A , Shoyusupov Sh , Chulliev Y
Published: July 2020

Agriculture in the Republic of Uzbekistan is based on irrigated agriculture, therefore, not all rivers existing in the country fully satisfy the needs of consumers, and water resources are accumulated mainly from reservoirs. From this point of view, the strength of the dams of these reservoirs has been studied in detail. However, in most cases, the external slopes of the dams of these artificial hydraulic structures are not used. This, in turn, requires new scientific solutions for the development of solar energy in Uzbekistan, where the amount of solar radiation is quite large. As an example, to study this problem, the amount of seasonal solar radiation in the southeastern region of the republic was obtained using simulation values using a geographic information system on the ArcGIS 9.3 platform and a seasonal map of solar radiation was developed. At the same time, to ensure the efficient operation of solar photovoltaic installations made of photovoltaic cells based on semiconductor silicon materials, it is proposed to use the external slope of the Talimarzhan dam located in this territory. This, in turn, makes it possible to eliminate the problem of preventing the drop in the coefficient of performance (COP) of solar photovoltaic cells, which is an important working part, with an increase in one of the most negative external factors - temperature.

The results show that based on the generated direct electric current from the solar photovoltaic station, the following can be supplied: lighting system for the reservoir, uninterrupted power supply of synchronous motors installed at pump station №7, consumers of auxiliary needs of the hydroaccumulative power station, which is planned to be installed in the reservoir, potential electricity consumption, consisting of from tourism services infrastructure to the development of ecotourism.
Scheme of conditioning in room based on evaporative air cooling system using solar energy
Authors: Anarbaev A , Zakhidov R , Mukhtarov F
Published: July 2020

The article is devoted to the development of promising low-power evaporative cooling systems using solar energy. At the same time, the placement of elements of the system in determining the temperature, the humidity of the air in such indoor areas is determined by the parameters at which the most favorable conditions for the optimal climate in the room are created. The article presents the structural and thermodynamic parameters of the developed two-stage evaporative cooler air. The creating two-stage evaporative cooling installation is shown the efficiency and effectiveness of the cooling air. Given preliminary studies where study the possibility of indoor climate and presented their results. Requirements to ensure the indoor climate. The test evaporative air cooler with rotated regenerative heat exchanger has a design air capacity of 160 m3 / h and 200 W in the cold, it provides for an independent change in the rotation speed of heat exchangers, a change in the amount of sprayed water. The total consumed electric power is not more than 45 watts. Achieved cooling 7°C at an ambient temperature of 35÷40°C (July-August 2019).
Dynamic calculation of boxed design of buildings
Authors: Usarov M , Mamatisaev G , Ayubov G , Usarov D , Khodzhaev D
Published: July 2020

A method for dynamic calculation of a box-like structure, consisting of interconnected longitudinal and transverse plate and beam elements is developed. The problem is posed of spatial vibrations of the box-like structure of a building under dynamic impact determined by its base motion according to a sinusoidal law. It is assumed that the external load-bearing walls of the building, perpendicular to the direction of the seismic effect, work on transverse bending only. The interior panels, located in the direction of external impact, are subjected to tension-compression and shear in their planes. Equations of vibrations of the points of panels, box beams, boundary and initial conditions of the problem are given. In the areas of butt joints of panels, full contact conditions are set to ensure the equality of displacements and stresses. Within the framework of the finite difference method, a methodology was developed for dynamic calculation of box-like structures. Numerical results of stresses over time in the hazardous areas of the box were obtained. The laws of changes in the maximum stress values in characteristic sections of the panels are graphically presented as a function of time.
Software package of mathematical modeling and structure for solving the dynamics problems of structurally-inhomogeneous shell structures
Authors: Salimov Sh
Published: July 2020

On the basis of the principle of modularity, an algorithm and software package for dynamic calculation of structurally-inhomogeneous multiply connected shell units that are the elements of hydro-technical structures are developed in the paper. The purpose of the module is to carry out certain transformations of the initial (source) information into a unique result. The development prospects of construction of various hydro-technical structures, aircraft, rocket and space machinery, shipbuilding, chemical engineering and many other branches of modern technology are characterized by a complication of design decisions in projecting and calculation of objects that present multiply connected spatial shell structures subjected to static and dynamic effects. Multiply connected structures, (such as hydro-technical structures), usually include a wide range of elastic and visco-elastic deformable elements with significantly different rheological properties in the form of blocks of plate stacks, tubular, cylindrical and prismatic shell structures of complex geometry, with attached masses, various types of reinforcement, supports, containing a large number of elastic and visco-elastic couplings with significantly different functions of heredity. Obviously, the search for exact analytical solutions to dynamic problems for structurally inhomogeneous visco-elastic shell structures is doomed to failure, the only possibility of engineering implementation is to build numerical and numerical-analytical algorithms with the subsequent use of modern computers. The solution to dynamic problems involves a numerical simulation of the stress-strain state (SSS) of the structures under consideration.
Modal analysis of frameless arches made of thin-walled steel profiles
Authors: Rybakov V , Jos V , Raimova I , Kudryavtsev K
Published: July 2020

The article is devoted to the modal analysis of frameless arch structures based on lightweight gauge steel structures (LGSS). The relevance of the study is due to the need to take into account dynamic effects when calculating the load-bearing capacity. Dynamic loads are a crucial factor affecting the stress-strain state of arch structures. The paper presents theoretical studies of the influence of the main geometrical parameters of the arch structure made of cold-formed thin-walled steel profiles on the first eigenfrequency. The dependences between the dimensions of arched structures and eigenfrequencies are obtained. It is proved that to determine the load-bearing capacity of frameless arch structures with the span L > 12 m, it is necessary to determine the eigenfrequencies of vibrations of the structure.
RETRACTED: The impact that crushed rubber can have on the quality of bitumen and asphalt concrete
Authors: Sidikova T , Barxanadjyan A , Hakimov R , Sabirova D , Mirsaatov R
Published: July 2020

The results influence of finale dispersed rubber crumb on the properties bitumen and asphalt concrete are presented in the study. The parameters of the optimal regime of bitumen and rubber crumb mixing are established. The influence on the rubber crumb mixing with bitumen or added directly in the process of asphalt concrete mixing on the properties of asphalt concrete is studied. The effects that fine rubber has on the properties of petroleum bitumen and asphalt concrete are measured. The best options available for combining bitumen and rubber crumb are given. Moreover, it is also described how and to what extend crumb can influence the quality of rubber-bitumen binder for roads and how rubber-bitumen binder is affected when crump is added to this asphalt mixture. The influence that rubber crumbs have on the quality of bitumen and asphalt concrete. In the study, the influence of crumb on the properties of bitumen and asphalt concrete are shown. The conditions at which a high-quality mixture of bitumen and rubber crumb can be produced. Furthermore, the effects of crumb on the rubber-bitumen binder and the direct introduction of crumb into mixture are thoroughly investigated.