bluuebunny/crossref_metadata_2025 huggingface dataset:
Designing and Building Secure Electronic Medical Record Application by Applying AES-256 and RSA Digital Signature
Authors: Wening Werdi Mukti Galih , Setiawan Hermawan
Published: July 2020

Medical records consist of health data that must be kept confidential and is regulated in Indonesian law. Until now the implementation of electronic medical records in Indonesia has not been clearly regulated in a law, while Regulation of the Minister of Health of the Republic of Indonesia state that medical records must be made in writing, complete, and clearly or electronically. In view of this, another approach than the regulation is needed to be able to meet the confidentiality of the data in the regulation, in electronic form. In this study, an electronic medical record application was designed and built that can meet the requirements of the legislation. The application encrypts patient’s health data stored on medical records using the AES-256 algorithm for data confidentiality. The use of AES-256 has been standardized based on the Federal Information Processing Standards Publication 197 and RSA Digital Signature digital signature because it has been standardized based on Federal Information Processing Standards Publication 186-4 and NIST Special Publication 800-89. The proposed application have been made have passed security testing using 6 testcase based on the reference paper.
Potential of processed timber for preserving the Chinese traditional buildings
Authors: Rilatupa J , Trisno R , Lianto F
Published: July 2020

As one of the ethnic groups that enrich the diversity of customs and culture in Indonesia, the Chinese people have a cultural characteristic that their ancestors brought more than 400 years ago to Indonesia. This certainly gives a great influence on various aspects, one of which is the building architecture. This study aims to examine the architecture of traditional Chinese buildings in the China Benteng area, Tangerang. This research aims to examine the architecture of traditional Chinese buildings in the China Benteng area, Tangerang. The research method used is a qualitative rationalistic approach with qualitative data analysis. In the Chinese tradition, a procedure for building houses cannot be separated from Fengshui, as in the temple building in the China Benteng area. Fengshui is very important in determining the building direction that is profitable so that it will get blessings and avoid disaster. Meanwhile, wood materials usage in traditional Chinese buildings such as the Boen Tek Bio temple is solid wood. If a renovation or replacement of wood material is needed, of course now it is difficult to find solid wood of good quality, such as when building the Boen Tek Bio temple. For building preservation needs, processed wood or engineering wood is commonly used as one of the building materials and can be considered if needed to replace damaged wood material in traditional Chinese buildings.
Design of Multiband MIMO Antenna for 5G Millimeterwave Application
Authors: Rusmono  , Sandi Efri , Marani Teresa
Published: July 2020

In this paper, design of multiband MIMO antenna by using patch and slot modification is proposed. The MIMO multiband antenna design uses the addition and modification of patch and slot shapes to obtain antenna performance in several frequency bands. In a previous study, the multiband antenna design only used the method of adding patches or slots separately. In this research, we tried to combine the addition of patches and slots together. The antenna design uses the substrate material Rogers RT5880 with a dielectric constant (εr
) 2.2 and height 0.787 mm. The dimensions of the MIMO multiband antenna developed by this study are 42.90 × 14.89 mm. Simulation and measurement results show that this MIMO antenna can work on several millimeter-wave frequency bands, 24 GHz, 28 GHz and 38 GHz. These results prove that the development of design techniques by adding patches and slots to microstrip antennas can produce antennas that work in several frequency bands.
Establishment of an application for photographs’ quality detection based on sharpness and light intensity
Authors: Hugeng Hugeng , Jevon Tjahyadi Ardis
Published: July 2020

Along with the booming of digital photography, camera users grow significantly, especially the users of digital single-lens reflex (DSLR) camera. There are many new users who apply their DSLR cameras for the first time and have little knowledge how to use them. That’s why an application is needed to guide a novice user so that he/she could get better understanding about photography. We have an idea to create such a guidance application that can provide evaluation and suggestion about the quality of user’s photographs. Thus, users can easily develop the ability of photography. Overall, the level of accuracy of this application in identifying deficiencies in the pictures taken is about 75%. This level of accuracy is calculated from errors that occur in detecting both sharpness of the pictures and light intensity (exposure) of the pictures, or any one of them. The errors in detecting the conditions of pictures, occur in some pictures. Hence, it needs further development of methods to improve the accuracy in all conditions of pictures taken. Best accuracy is necessary so that the proper suggestion is given by the application in accordance with the actual condition of the picture.
North Coast Jakarta Land Reclamation as a Solution of Land Requirements
Authors: Tjoei Agustina , Kesuma Meyriana , ST  , MT
Published: July 2020

North Coast Jakarta land reclamation policy is a comprehensive effort undertaken by the city administration to increase space requirements in Jakarta. Interpretation of the North Coast Jakarta land reclamation policy and provisions of the spatial plan raises various debates on the pros and cons. In the implementation, there are still two conflicting sources of law on this reclamation policy, between Presidential Decree No. 52 of 1995 and Presidential Decree No. 54 of 2008. The peak was in June 2018, Jakarta Governor Anies Baswedan stop and seal all the property on the reclaimed land due to not completing a building permit. This action became a new polemic reclamation. The study was conducted with a descriptive-analytical method, which describes the underlying spatial phenomena and has an impact on the North Coast Jakarta land reclamation specifically at D Island “Gold Island”. The results of this study indicate that land reclamation is a necessity for the city that has highly increasing of population growth rate. Facts implementation of the land reclamation project on D island until now contrary to the main purpose of land reclamation of North Coast Jakarta. The complexity of the implementation land reclamation project comes from the inconsistency of policies and orientation of economic benefits. The orientation of economic benefits from extra spaces on D island is a form of capitalist space and ignores the social space. On the other hand, there is no benefit in terms of environmental, economic, and social for North Coast Jakarta local communities
Characteristics Analysis of Slum Area in the Region of Rw 16 Kapuk, West Jakarta
Authors: Devina Halim Jemima
Published: July 2020

The area, which is located in RW16, Kapuk, West Jakarta, is one of the residential areas which is categorized as one of the slum areas. This article is part of a research on directives to improve the quality of the environment of slums in RW16 Kapuk, West Jakarta. In this article, we will discuss the stages of identifying the characteristics of the environment of slums located at each level of slums found in RW16 Kapuk, Jakarta using the Descriptive Qualitative Analysis technique. After identification, the characteristics of slum area in the study area are obtained in terms of 5 aspects, namely physical, economic condition, availability of facilities and infrastructure, social, and also danger. (hazard).
Implementation of incognito method and SHA-3 as an alternative to PIN selection in web login
Authors: Deta Hendika Wardani Gesi , Restu Pramadi Yogha
Published: July 2020

Currently, the PIN is still used to verify identity on web-based applications. PIN is widely used because it is easy authentication. However, a PIN has a potential security risk that is vulnerable to shoulder surfing attacks. The way to reduce shoulder surfing attacks is to create an interface that is difficult to attack with shoulder surfing attack techniques. One interface that can be applied is the incognito method. In this research, the application of the incognito method is implemented as a web login application. The application is built based on the web using the SHA3-256 algorithm to hash the PIN. The results of the stufy prove that the application built is resistant to shoulder surfing attack by attackers.
Predictive Calculations of the Bulk Water Reservoir Capacity Using a Geographic Information System
Authors: Bakiev M , Babajanov K , Babajanova N
Published: July 2020

The Tuyamuyun hydro-complex on the Amu Darya River, consisting of one in-channel and three off-channel basins with a design volume of 7.8 billion m3, was intended to improve the supply of irrigation water and electricity to the Khorezm region and the Republic of Karakalpakstan and to control the catastrophic floods in the lower reaches; it was put into operation in 1984. The water reservoir complex is in joint use by the Republics of Uzbekistan and Turkmenistan. Numerous measurements showed that the useful volume of the reservoir due to siltation decreased from 2.34 billion m3 to 770 million m3, i.e. by 67%. To partially compensate for the lost capacity, it was proposed to build-up the protective levees and to erect the new dams, where the topography of the area allowed. Using the GIS, the predictive volumes to increase the capacity of the Channel water reservoir have been proposed, depending on the water level in the reservoir, which between the marks ▽130.0 and ▽131.5 amounted to 527.3 million m3. The necessity was shown to increase the height of the following protective dams: No. 1
▽134.5, No. 2
▽134.8, No3
▽136.7, No. 4
▽134.4, No. 5
▽136.4. No. 6
▽137.9, No. 8
▽138.6, No. 9
▽135 and land dam 134.8.
Hydrodynamic loads on a water drain with cavitation quenchers
Authors: Obidov B , Vokhidov O , Shodiev B , Ashirov B , Sapaeva M
Published: July 2020

The data on the hydrodynamic loads on the water body in the presence of cavitating energy without erosive dampers on it are presented. It is shown that these loads increase in comparison with the non-cavitation mode, but, despite this, the use without cavitation dampers in appropriate conditions is advisable, providing favorable downstream regimes and reducing the volume of construction work and the cost of construction. It is proved that for multiple types without erosive energy absorbers, data were obtained on the averaged and pulsating vertical and horizontal loads on the absorbers and the slaughter plate, which allows us to carry out the required calculations of the strength and stability of the elements of the downstream devices. As a result of cavitation and cavitation studies of erosion-free energy absorbers in cavitation stands, coefficients of any resistance C

x
of several types of aerosol-free absorbers were obtained; as well as pulsation standards measured by “point” sensors for the vertical hydrodynamic effects of the flow on the water culvert in the installation zone of an erosion-free damper.
New methods for geoinformation systems of tests and analysis of causes of failure elements of pumping stations
Authors: Ergashev R , Bekchanov F , Akmalov Sh , Shodiev B , Kholbutaev B
Published: July 2020

The large pumping stations (PS) planned for reconstruction in our republic in terms of consumption, power-to-weight ratio, and controls are the largest in the world: failure of them even for a small period of time can lead to enormous damage. Therefore, the formulation and solution of theoretical problems in the operation of these facilities, taking into account the reliability indicators, is an extremely important national economic task. Until now, the design of the National Assembly, including large ones, has been conducted without taking into account the quantitative index of reliability. The value of reliability has long been underestimated, and error correction required significant costs. Currently, increasing the efficiency of the operation of pumping stations is associated with the development of energy-saving and resource-saving technologies. Diagnostics is one of the modern and perfect ways to determine the main malfunctions that occur in pumping units. The main goal of diagnosing the technical condition of pumping units is to preliminarily identify the occurring malfunctions in it and ensure durability, reliability, reliability, and operational efficiency. The article presents the effect of vibration on pumping units and analysis of methods of vibration diagnostics, information is given on the possibility and advantages of devices for continuous vibration diagnostics.
Throughput of the water of shutter with flexible working bodies
Authors: Kadirova M G
Published: July 2020

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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
Justification scheme installation of a rotary working body for opening grape bushes
Authors: Turakulov M , Ermatov V
Published: July 2020

The article describes the nature of the movement of a non-driven rotary working body when working in row aisle: portable with speed V

n
and relative (rotational) around the axis of rotation with angular velocity ω. The technological process of the operation of a non-driven rotary working body can be divided into three main interrelated points: the introduction of the dump into the soil, the descent of the soil from the surface of the dump, and the flight of soil particles discharged from the working body.

And also a diagram of the interaction of the blade of the working body with the soil. When a soil particle moves along the surface of the dump in the active working zone, where due to the soil cutter, the extreme point of the dump moves with acceleration, a force arises pushing the soil particles from the surface of the dump. Knowing the forces acting on the particle and the scheme of their action, it is possible to compose the differential equations of the soil on the surface of the dump. Formulas are given that determine the flight range of soil particles descending from the dump of a rotating working body. The length of the flight path of the soil particles after the descent of their working body is determined. The direction of soil displacement also depends on the inclination of the non-power rotary working body relative to the soil surface (horizon). When the rotational working body is tilted towards the row, the soil particles move to the middle of the aisle.
Pole-changing windings for turbomechanism engines
Authors: Rismuhamedov D , Tuychiev F , Rismuxamedov S
Published: July 2020

The article substantiates the relevance of the development of pole-changing windings for turbo-engins. There is a review of specialized literature on the development of pole-changing windings. Two-speed motors with a 4/3 pole number ratio have one pole-changing stator winding by the method of PAM. Based on the method of “Discretely specified spatial function” a pole-changing winding is obtained for a 3/4 pole ratio with 72 stator slots. The analysis of the electromagnetic properties of the obtained winding is carried out. The correspondence of the obtained winding for use in turbo-mechanisms is revealed. As a result of the study, there were procured the stator windings at 6 and 8 poles, which enabled to change the spin speed of the motor in the fan drives without breaking the drive power circuit by the scheme ΥΥΥ/ΥΥΥ with additional branches
Selection of the number of teeth of the sprockets of the soil seeder
Authors: Duskulov A , Isakov A , Jalilov Z
Published: July 2020

Presowing tillage allows you to lay a solid foundation for friendly and healthy seedlings, as well as a high crop of crops. For its implementation, a whole range of work is required to prepare the soil, which is carried out by plows, cultivators, harrows, and other agricultural machines and implements.

In the soil and climatic conditions of Uzbekistan, soil preparation for cotton sowing is carried out in the spring, on autumn plowing, while depending on the state of the field, differentiated fields are cultivated: partial planning, subsurface cultivation, chiseling, cultivation, harrowing with praying. At the same time, the composition of the soil prepared for sowing does not always meet the required quality of the structural-aggregate composition, the soil becomes coarse, and the top soil layer is very compacted. This situation prevents the high-quality implementation of the technological process of sowing cotton seeds of a cotton seeder.

One solution to this issue is the active loosening of the soil in the area of cotton seeds with simultaneous sowing on one unit.
Innovative technologies in the effective use of water resources
Authors: Sherov A , Urinboev S
Published: July 2020

Global warming in the arid region is currently exacerbating water scarcity. The use of groundwater for crop irrigation is one of the major problems in the world. In this context, the use of rivers and ponds with varying degrees of mineralization is especially important for the irrigation of crops. About 300 km3/year of collector-drainage water (CDW) is formed in the world, which causes great damage to the economy and nature of all countries of the world. In this regard, one of the important tasks is the development of measures for the reuse of collector-drainage water for irrigation, the first demineralization, and disinfection, or their use in combination with river water. To solve these problems, a neutron-active analysis of the composition of the soil and trace elements were studied, as well as the dynamics of the distribution of water in the active soil layer to determine the patterns of water absorption in active soil during irrigation based on a new innovative method of nuclear physics and irrigation of cotton plantations with the addition of drainage water and as a result of which, there was provided the efficiency of water use and increase the productivity.
Methods of managing the agricultural background of cotton and technical means for their implementation
Authors: Shaimardanov B , Isakov A , Mirnigmatov B
Published: July 2020

In the complex of measures aimed at reducing the laboriousness of cultivating and growing high yields of raw cotton, a major role is given to further improving the technology and means of mechanizing cotton sowing. In recent years, rainy weather has been observed during the period of sowing cotton, as a result of which the germination of cotton seeds is significantly delayed. When showers, puddles form on the traces of the seeder, which leads to rotting of the seeds, as a result of which repeated sowing is carried out. When cultivating cotton on the ridges, in accordance with the theoretical foundations of soil cultivation, a favorable composition of the arable layer is ensured for a long period of cotton growing. This contributes to friendly shoots, good plant development and a high yield of raw cotton with early ripening, moisture accumulation on the ridges eliminates soil pollination, destruction of the structure, and formation of soil crust. Using the drip irrigation system allows to provide plants with water and fertilizers, where necessary, at the right time and in the right amount.
Stabilization of mechanical systems with nonholonomic servoconstraints
Authors: Khusanov K
Published: July 2020

The proposed work is devoted to the study of mechanical systems with releasing nonholonomic servoconstraints on controllability and stabilization. In this case, the reaction forces of the servoconstraints are decomposed into the normal and tangent components. The factors of tangent components are taken as control parameters. A technique is proposed for determining the reaction forces of servoconstraints providing stabilization of motion relative to the variety determined by nonholonomic servoconstraints. As an example, the problem of a gyroscope in a cardan suspension with nonholonomic releasing servoconstraints is considered.
The results of the experimental nature of the vibrations of the grid cotton cleaner
Authors: Shodiyev Z , Shomurodov A , Rajabov O
Published: July 2020

The article provides a new effective scheme and principle of operation of a multifaceted grid of cotton cleaner from small trash. The results of comparative experimental studies of the grid oscillations and the nature of loading depending on the parameters and modes of cotton cleaning are presented. In the experiments performed, the nature of the vibrations was investigated by studying the component vibrations of two grids simultaneously to compare the results. An analysis of the obtained laws of grid vibrations showed that the amplitude of the recommended multifaceted mesh surface on the elastic supports exceeds the amplitude of vibrations of the existing grid 5–7 times and reaches up to (2 ÷ 2.5) × 10−3m. In this case, the oscillograms are presented for steady-state modes of the work of the cotton cleaner. The results show that an increase in the coefficient of the number of faces of the grid leads to a decrease in the load of the grid to (0.3 ÷ 0.5) N. The parameters of a multifaceted grid of cotton cleaner from small trash are substantiated. Experimental studies have studied the workload and the law of vibrational motion of the grid surface.
Descrease in noise and vibration of single-phase asynxronous motors in rolling stock
Authors: Gapparov A , Berdiyev U
Published: July 2020

The article describes the magnetic noise during the operation of a single-phase asynchronous motor due to the vibration of the stator package of the motor under the action of vibration-absorbing forces due to the interaction of harmonics of a magnetic field of various origins in the air gap of the machine. As a normalized parameter of vibration created by an electric machine, the effective value of the vibration velocity is adopted. Electric motors used in electric rolling stock operate in more difficult conditions in comparison with general industrial ones. In the electric rolling stock, various auxiliary electric machines are used. Despite the relatively low level of magnetic vibration of high frequency, due to its determining effect on the magnetic noise of single-phase motors, this component is of independent interest for research.
Research of the operating process of disc displaying machine of potato landing machine
Authors: Makhmudov Kh
Published: July 2020

The level of potato production in the developed countries of the world is characterized by the stability of yields reaching up to 45 and more tons per hectare. High potato production in developed foreign countries is achieved through a systematic approach at all stages and technological operations of cultivating and harvesting using advanced technologies and modern technical means.

At the same time, in our country, the gross harvest of potatoes from 78.8 thousand ha is 1.717 million tons, that is, the yield per hectare is 21.8 tons. This significant difference in potato yields between domestic and foreign producers is due to several reasons:

- in our country, about 90 % of potatoes are produced mainly on small-contour and scattered plots with an area of 0.2-1.5 hectares of dekhkans and farms. In such areas, the simplest technologies with a low level of mechanization are used;

- low level of provision of potato producers with high-quality seed materials, as well as low-quality planting calibration of tubers in size, which has a significant impact on the quality of work of potato planting machines;

- the lack of domestic potato planting machines differing in the quality of the uniform distribution of tubers during planting, since the quality of the machine depends on this factor;

To successfully solve these and other problems of increasing potato productivity, it is necessary to solve the accuracy of dosing potato tubers and their uniform distribution during planting.