bluuebunny/crossref_metadata_2025_split huggingface dataset:
Throughput of the water of shutter with flexible working bodies
Authors: Kadirova M G 
Published: July 2020

Abstract
The author together with Bochkarev V developed a hydraulic automatic water level controller with flexible working bodies. To determine the throughput and determine the optimal profile shape of the weir of its shutter, experimental studies were conducted. They were carried out by the method of physical modeling of the model and nature in an experimental setup, with the study of three types of shutter models with flexible working bodies with the shapes of a part of the spillway in the form of a board, non-vacuum and elliptical vacuum profile. Based on the results of these studies, without and with a side stream, formulas and dependency curves are obtained for determining the flow rates of the spillway with three forms of its part of the spillway. An analysis of the results of the study showed that the shutter with the spillway non-vacuum profile without has a slightly lower throughput than others, but is characterized by stable operation without vibration and is therefore recommended for use.
Algorithms for choosing a design solution for transforming a relief
Authors: Kuchkarova D , Achilova D 
Published: July 2020

Abstract
The article deals with the creation of algorithms for selecting a project of territory in the process of transforming a relief into a project surface. The selection function and the design problem are defined. Such tasks belong to the class of multicriteria optimization problems. At present, adaptive procedures based on a dialogue between a decision-maker and a computer is being successfully used. Such procedures are focused on the search for effective (Pareto optimal) alternatives. A modification of the “shifted ideal” method is proposed. Here, at the first stage, an “ideal” object is formed from the maximum utility values of the criteria. Also, the “worst” object is formed from the minimum criteria values in terms of utility. In the second stage, units of measurement are formed that allow us to estimate the distance of the object from the “ideal” object. At the next stage, the distance of each design solution to the ideal is calculated. Then design decisions are ranked by distance from the “ideal” project and are removed from the original set: the search for the optimal design solution continues until an option is found that is preferable for the decision-maker
Water impermeability of hydraulic concrete based with thermal power plant waste substrate
Authors: Yunusova F , Muslimov T 
Published: July 2020

Abstract
One of the main factors in ensuring the reliability of concrete used in the construction of hydraulic and reclamation facilities is their waterproofing and frost resistance, and the design of the optimal composition of concrete to ensure waterproofing is of great importance. The main goal of the study was to select the water/cement ratio of the concrete mix not only in terms of concrete strength but also in terms of concrete strength, to ensure the optimal concentration of aggregates for dense structural concrete and finally to increase the water permeability of hydraulic concrete using microfillers and chemical additives. In the study, industrial ash (Angren Thermal Power Plant) was used to modify technical lignosulfonates and prepared a plasticizer L-2 chemical additive. Studies have shown that if the size of pores and capillaries that occur in the concrete structure is less than 10-5 cm, they will not allow free water to pass through. But if these dimensions are larger than 10-5 cm, they will have the property of water permeability. The size of the pores formed in the cement gel, which is usually used in the preparation of concrete, is less than 10-5 cm, and they are impermeable to water. However, the sizes of capillaries and pores of different sizes formed in the concrete structure may vary depending on the factors listed above (10-6 - 0.2 cm). Based on the research, the technological factors affecting the waterproofing of hydraulic concrete were analyzed. It was argued that the use of L-2 plasticizer chemical additive in the amount of 0.25% of the cement mass in the preparation of hydraulic concrete can reduce the water-cement ratio by 18% and increase the waterproofing of hydraulic concrete by 3 times. In addition, it was considered that by waterproofing open pores and capillaries in freshly poured concrete, their waterproofing can be increased by 20. … 30 times.
Free oscillations of three-layered plates
Authors: Abdikarimov R , Usarov D , Khamidov S , Koraboshev O , Nasirov I , Nosirov A 
Published: July 2020

Abstract
The paper is devoted to improving the theory of bending and vibrations of three-layer plates with transverse compressible filler and thin outer bearing layers. For the outer layers, the Kirchhoff-Love hypothesis is accepted and the motion of their points is described by the equations of the theory of thin plates relative to forces and moments. Unlike bearing layers, a filler is considered as a three-dimensional body that does not obey any simplifying hypotheses. The equations of the bimoment theory of thick plates with respect to forces, moments and bimoments, created in the framework of the three-dimensional theory of elasticity, taking into account the nonlinearity of the distribution law of displacements and stresses over the thickness, are taken as the equations of motion of the filler. Expressions of forces, moments, and bimoments in the layers, as well as boundary conditions at the edges of a three-layer plate with respect to force factors, are given. In the conjugate zones of the layers, the complete contact conditions for the continuity of displacements and stresses are set. An example is considered and numerical results are obtained.
Optimal control of unstable water movement in channels of irrigation systems under conditions of discontinuity of water delivery to consumers
Authors: Rakhimov Sh , Seytov A , Nazarov B , Buvabekov B 
Published: July 2020

Abstract
The object of research was the site of the South Golodnostepsky main channel, located in the north-east of the Republic of Uzbekistan. Scientific and research work is being carried out in the world aimed at improving and developing methods, quality criteria, developing mathematical models and algorithms for solving problems of optimal control of the operating modes of water facility using modern information systems. We used methods of mathematical modeling and optimal control of systems with distributed parameters, which is considered the main channel. The optimum changes in water levels at times and along the length of the section of the main channel are obtained, and its open gates allow increasing the water level along the length of the section. During t = 20.7 minutes the water level at the end of the main channel section rises by 1.8 meters.
Water distribution on machine canals trace cascade of pumping stations
Authors: Rashidov J , Kholbutaev B 
Published: July 2020

Abstract
The article describes the cascades of the main pumping stations in the Commonwealth of the Independent States and Uzbekistan, it is noted that, despite their complexity and many problems, there is almost no information in the literature and very little research has been done. The main goal of the article is to schematically and theoretically show the results of field studies in a system of cascades of pumping stations Amu-Zang-Bobotag in the Surkhandarya region.
Effect of hydrogels on moisture storage of irrigated automorphic soils in Uzbekistan
Authors: Salokhiddinov A , Hamidov A , Khakimova P , Mamatov S , Boirov R 
Published: July 2020

Abstract
An experimental study on the development of water-conserving irrigation technology with the use of super swelling hydrogels synthesized out of local raw material has been conducted for three years under the condition of arid automorphic soils of western Uzbekistan. The development of new and affordable water-conserving technologies is critical for the sustainable development of irrigated agriculture in arid zones that severely affected by growing water scarcity. The experiments were aimed at determining the properties of hydrogels, establishing quantitative indicators of the water-holding ability of automorphic soils depending on the methods, norms, and time of application of highly swellable polymer hydrogels under conditions of cotton cultivation. The experiments were conducted under conditions of the irrigated by lifted water automorphic soils and cultivation of the Andijan-35 cotton variety. Results of the study show that use of highly swellable polymer hydrogels with a norm of 50 kg/ha under traditional agrotechnology conditions in conditions of automorphic soils based on improved traditional furrow irrigation technology allows reducing water consumption for irrigation by 15-17% in the first year, by 12-14% in the second year and by 9-11% in the third year of experiments. Due to the longer duration of moisture conservation in the soil, the period between irrigations is extended by 10-12 days, the number of irrigations is reduced.
Numerical modeling of two-dimensional two-phase filtration under frontal drive
Authors: Mirzaev S , Kholmatova I , Shodmanova G , Yusupov M , Kubyashev K 
Published: July 2020

Abstract
The problem associated with the development of gas fields with confined contour water is considered in the paper to increase gas recovery and determine the main indices of the reservoir, as well as the position of the moving boundaries for further development. To conduct a comprehensive study of the process under consideration, a computer model was developed described by a differential equation with the corresponding initial and boundary conditions. An algorithm was developed to solve the problem using the methods of the longitudinal-transverse scheme and the flow version of the sweep method. The results are validated with a test example and an example of a certain real object. The results are shown in the form of tables and isolines. Numerical experiments have shown that using this statement it is possible to apply the developed algorithms and software systems to solve the problem during field development.
Soil salinity mapping by different interpolation methods in Mirzaabad district, Syrdarya Province
Authors: Pulatov A , Khamidov A , Akhmatov D , Pulatov B , Vasenev V 
Published: July 2020

Abstract
Soil salinity is an important global issue and especially on irrigated areas due to its great impact on a crop production system. Proper soil salinity mapping can improve land use management. The goal of this study was to improve the accuracy of soil salinity mapping with the two objectives (1) to evaluate different interpolation methods during soil salinity mapping and (2) to identify of differences in soil salinity assessments in irrigated land of Mirzaabad district which is most affected by salinity in Syrdarya province of Uzbekistan. Soil salinity data measured by EC meter was obtained from Syrdarya Hydromelioration Expedition. Different four interpolation methods such as Inverse Distance Weighted (IDW) with power 1, 2, and 3, and Kriging techniques were used for the generation continuous surface of soil salinity maps. The cross-Validation method with the assessment of Root Mean Square Errors (RMSE) shows that IDW with power 2 (IDW-2) most accurate. The maximum difference reached between IDW-2 and IDW-1 on the slightly saline area where the value decreased by 55% of the total irrigated land of the district. Minimum differences reached on IDW-3 on moderated saline class and higher than IDW-2 on 408.6 ha.
Rational use of collector-drainage water
Authors: Mirkhasilova Z , Irmuhamedova L , Kasymbetova S , Akhmedjanova G , Mirkhosilova M 
Published: July 2020

Abstract
The greatest importance in the Republic of Uzbekistan is given to water management. The problem of water resources lies in the irrational use of collector-drainage waters, which lead to a deterioration in the quality of river waters. Of the existing collector-drainage waters in Uzbekistan, water with a salinity of up to 2 g / l makes up 38%, with a salinity of up to 3 g / l makes up 23%, with a salinity of more than 3 g / l, sometimes reaching up to 10 g / l makes up 37% of the total volume of collector-drainage water. With an increase in mineralization, the amount of toxic salts decreases, and these waters also contain a large number of pesticides and herbicides. Some of these waters are used for irrigation, the rest is dumped into depressions or rivers creating an environmentally unfavorable environment. Measures are necessary for the disposal and rational use of collector-drainage water, which will improve the environmental situation and may be an additional source of irrigation in a dry period. The object of research is collector-drainage water forming in the Ferghana region of the Republic of Uzbekistan. To solve this problem, it is necessary to improve the environmental situation and it is recommended that three points be implemented:
• study the existing volume of collector-drainage water and use it for irrigation;
• apply new technologies aimed at water saving during irrigation;
• do not discharge pumped water from vertical drainage wells with good mineralization into the drainage network.
Applying these technologies, it is possible not only to improve the condition of irrigation water but also to use water as an additional source of irrigation. By covering the deficit of irrigation water with drainage water and rational redistribution of the water limit from the source between the districts, the water supply in the regions is equalized and will reach 50-70 percent, and the water supply in the region will increase.
Water availability and water use planning in the Aral Sea basin
Authors: Ramazanov A , Buriev S , Koshekov R 
Published: July 2020

Abstract
According to the forecast of international, regional, and Republican research institutes and design and survey institutes, in the current water management situation in the Aral Sea basin, the shortage of water resources will increase over time and space. Currently, the water supply of the territories located in the middle and lower reaches of the Syr Darya and the Amu Darya rivers does not exceed 60-70% of the required volume, which causes significant damage to agriculture. The consequences of low water are quite noticeable in areas located in the middle and lower reaches of rivers.
There are different points of view in the Republic about the possibility of mitigating water scarcity through widespread water conservation, effective regulation of river flow, improvement of operation and technical equipment of irrigation systems, the introduction of water-saving technologies for irrigation, cultivation, and introduction of drought-resistant crops. Without detracting from the importance of these measures, first of all, it is necessary to forecast and quickly establish the water level of the main water flows in the near future, and widely introduce organizational and technological methods to increase the productivity of water entering irrigated fields into production practice.
Analysis of the results of long-term observations and expert assessments in various parts of the irrigated zone indicates the presence in a wide production practice of cases of irrational use by farms of water allocated by the limit, un-planned by agricultural technology surface discharge into the existing collector-drainage network. The article presents the results of calculations of water use planning taking into account the water availability of the territory on the example of the Republic of Karakalpakstan.
The purpose of the study is to develop organizational and technological bases for planning water use in their limited capacity, taking into account the water availability of territories on the example of the Republic of Karakalpakstan. When determining the area, composition, and structure of agricultural crops, the water availability coefficient (%) actual (m3) and required water intake (m3) to the territory are taken into account. As initial data, the results of long-term systematic observations, measurements, and expert assessments of operational and planning water use organizations of the Ministry of agriculture of the Republic of Karakalpakstan were used. The calculations were performed using a computer program compiled jointly with specialists of the Nukus State University and tested on the example of individual irrigation systems, channels, and administrative districts of the water users Association.
The recommended procedure for the rapid establishment of acreage and crop structure, depending on water availability conditions, does not harm the functioning infrastructure of agricultural production.
Features of the friendship processing the cotton washing machine vertical spindles
Authors: Shaumarova M , Abdillayev T , Sarimsakov B , Yusupov Sh 
Published: July 2020

Abstract
The benefits of the vertical spindle picker and its main disadvantage are the facts that the frictional rotation of spindles around their axes is largely due to the decline in cotton picking. It is explained that the absolute velocity of the tooth is to be within certain limits so that the spindle tooth can be trapped, and that the tooth has sufficient velocity for the tooth to pull out the cotton fibers. The absolute speed of the tooth depends on the geometric sum of Vm, the velocity of the drum, the velocity of the drum VB, and the spin speed of the spindle. Vm and VB are not changed, but Vs vary for different reasons. As a result, the direction and extent of the tooth’s absolute speed changes, and the dialing rate decreases. The authors believe that friction ribbons should be at their intended level to prevent the fall in cotton harvesting.
Energy efficiency and renewable energy sources in the agricultural area
Authors: Radjabov A , Nabiev S 
Published: July 2020

Abstract
The article highlights the methodology for quantifying energy efficiency and the principles of using renewable energy sources in the processes of production of final products of the agricultural sector. Domestic and foreign scientists carried out a large number of fundamental and applied research aimed at increasing energy efficiency and reducing the energy intensity of agricultural production and certain positive results have been achieved [3]. We have developed a scientific and methodological basis for increasing energy efficiency in agricultural production. considering the energy technological process and the energy source in a single system, “energy resources-bio object” using the laws of conservation, movement, and absorption of energy [4] New indicators and criteria for evaluating the energy efficiency of agricultural products such as bioenergy efficiency coefficient and useful coefficient of energy use, taking into account the biological characteristics of agricultural energy consumers (technological facilities) [5, 6]. New electrical technologies for the processing and storage of agricultural materials and products, disinfection of water, and other biotechnological objects with the use of electrophysical and electrochemical effects [7, 8] were developed.
Full-scale testing of the pump unit with a frequency converter
Authors: Kan E , Mukhammadiev M , Ikramov N , Majidov T 
Published: July 2020

Abstract
It is generally agreed that when using the frequency converter at pumping stations, the economic effect of its use far exceeds the losses in efficiency, and naturally, no comparison between the alternative methods of regulation is given. But, as a practice has shown at the application of the given control method, losses in efficiency can be essential. Quantitatively these losses depend on many factors (degree of regulation, type of the applied frequency converter, pumps and the driving electric motor, operating modes etc.). Therefore, for an accurate assessment of the efficiency of the control method, field tests of the unit with a frequency converter are necessary. Full-scale tests were carried out at the Teshik-Tash-1 pumping station located in the Andijan region of the Republic of Uzbekistan. The field tests consisted of determining the efficiency of the pump unit when the drive shaft speed changes. Graphical dependencies of changes in the energy parameters of the pump unit when changing the rotation frequency of the impeller shaft using a frequency converter are obtained. Tests have shown that loss values can reach significant values when using a frequency converter. If you reduce the speed of the pump impeller by 10 %, the efficiency of the electric drive (motor and converter) will also decrease by 10 %, and if you change it by 25 %, the efficiency of the electric drive may decrease by up to 40 %. The test results can be applied in the selection and feasibility study of the regulation method at irrigation pumping stations equipped with pumps of type D.
Geological structure of the dam base as a factor of its reliability during flood periods (Hanoi)
Authors: Fomenko I , Dinh H , Sirotkina O , Barykina O 
Published: July 2020

Abstract
The object of study is a system of protective dams in Hanoi. In the new social and political conditions of Vietnam’s transition economy, the transformation of the riverside territories is of great importance for both the city of Hanoi and the country as a whole. A special role is given to the system of dams along the Hanga River (Red), which protect the city from floods. During the long history of construction and operation of the dams in Hanoi, many cases of their damage and destruction are known. The aim of the study is to assess the sustainability of the dams, the possible mechanisms of dam stability loss due to changes in hydrological conditions are examined. By mathematical modeling, the stability of the dam slopes and filtration strength of its base soils are calculated due to an increase in time during flooding hydraulic gradient. This task was solved in the flat setting, meanwhile, filtration modeling was carried out by the finite element method, and the estimation of the dam slopes stability was carried out based on the limit equilibrium method. The mathematical modeling allowed to estimate the dam stability from two positions: 1) change of the dam slope factor safety in time during the flood period; 2) increase of the hydraulic gradient in soils of the dam base during the flood period. The results obtained showed that the reliability of the dam depends both on the thickness of the clay layer at its base and on the duration of flooding. The factors we have identified that affect the stability of dams during flood periods can be used for predicted purposes to assess their reliability.
Non-contact controlled voltage stabilizer for power supply of household consumers
Authors: Karimov R , Bobojanov M , Tairova N , Xolbutayeva X , Egamov A , Shamsiyeva N 
Published: July 2020

Abstract
The article discusses the principle of operation of an optoelectronic voltage relay for switching windings of a boost voltage transformer of a voltage stabilizer. Based on the simulation of the proposed optoelectronic contactless voltage stabilizer using the MATLAB R2014a program, it was determined that the change in the shape of the output voltage curve is close to a sinusoid and coincides with the results obtained by the experimental path. When modeling a voltage stabilizer, the structure of the circuit does not change, but the parameters of the resistor elements corresponding to the open or closed state of the semiconductor device at the time of switching the vents change. The characteristic of voltage changes “input-output” and the analysis of existing voltage stabilizers on the principle of “quality voltage” in rural areas