bluuebunny/crossref_metadata_2025_split huggingface dataset:
The calculation of the rates in the swirling flow for the confuser section
Authors: Yangiev Asror , Adjimuratov Dilmurat , Gapparov Furkat , Yunusova Farida 
Published: July 2020

Abstract
The advantages of using aconfuser section in the outlet part of the vortex spillwayare shown in the paper; they may be more rational in terms of ensuring cavitation-free operation of the flow swirler. An analytical method for calculating the aerated swirling flow in the confuser section of the vortex spillway is presented, as well as its correspondence to experimental results, which allow us to quickly and accurately conduct the distribution analysis of axial and tangential rates in the swirling flow along the length of the confuser at different taper angles.
Methods of regulating the work of units at irrigation pumping stations
Authors: Kan Eduard , Mukhammadiev Muradulla , Ikramov Nazir 
Published: July 2020

Abstract
Irrigation pumping stations are one of the main elements of irrigation systems and the main consumer of electricity in the agricultural sector of the Republic of Uzbekistan. Therefore, the question of choosing a method for regulating the operation of pumping units is very important. Most irrigation pumping stations in the Republic of Uzbekistan are equipped with centrifugal pumps of type “D”. The main types of regulation for such pumps are: impeller trimming, changing the frequency of rotation of the impeller, the pumping unit switching on and off control method. The specific features of the operating modes of irrigation pumping stations revealed are. The analysis of various methods for regulating pumping units during the operation of irrigation pumping stations showed that, according to the degree of coverage of the water consumption schedule, the most optimal methods are valve control and a change in the rotational speed of the impeller shaft. Regulation by changing the speed of rotation and the pumping unit switching on and off control method more suitable according to the economy criterion. Calculations for the pumping stations “Ulugbek II”, “Kizil-Bayrak”, “Ittifok”, “Navoi” and “Turkiston” showed that with a change in the diameter of the impeller, the energy savings can reach 21.1-63.5%. When using a frequency converter at the same pumping stations, energy savings can reach 16.5-35.4 5%. It must be taken into account that, when turning, regulation is possible only in the direction of decreasing parameters.
Space-planning decisions of sanitary facilities of residential buildings in Russia
Authors: Orlov Evgeny 
Published: July 2020

Abstract
Currently, in the practice of designing residential buildings in Russia, sanitary facilities are given a secondary role, which reduces the level of comfort when living in an apartment. Architects are trying to give more space to all other rooms of the apartment, reducing the area of sanitary facilities. In the work, using the examples of residential multi-apartment buildings built in recent years in Moscow and the Moscow Region, the planning decisions of modern apartments, in particular their sanitary facilities, were studied and analyzed. It was concluded that the modern space-planning decisions of the sanitary facilities do not meet the requirements for the comfort of sanitary-hygienic procedures: small areas, lack of space for furniture, irrational installation of engineering equipment, not suitable for people with disabilities, etc. New space-planning solutions have been developed for one-room, two-room and three-room apartments, which will satisfy the end users and create a comfortable living environment in apartments of residential buildings.
The nitrifying rate of Sequencing Batch Reactor when apply bio-carrier the Biochip to municipal wastewater treatment
Authors: Gogina Elena , Ha Quan Tran 
Published: July 2020

Abstract
All around the world, the biofilm is the typical method for modification the municipal and industrial wastewater treatment plant. In the activated sludge reactor, the biofilm carries more suspended bacterial through the attached and growth of microorganisms on the surface of bio-carrier. Therefore, the article evaluates the performance of bio-carrier Biochip 25 in the Sequencing Batch Reactor (SBR) – a variation of activated sludge and has been wide applied in municipal wastewater treatment plant. The experiment proceeded in 2 phases, based on 2 main kind of pollutants in wastewater: 1. Organic matters in typical model SBR; and 2. Nutrients, especially ammonia – nitrogen in modification model with anoxic step. The quality of treated water from the model SBR with Biochip shows that, the efficiency of biological treatment stabilizes in range 80 – 90% with organic matter and 75 – 85% with Ammonia – Nitrogen. In modification model SBR, the specific denitrification rate stabilizes in range 0.3 – 0.4 Nred/kg sludge/day and the nitrification rate in range 0.18 – 0.20 kg Nox/kg sludge/d. Moreover, the specific rate and the balance of nitrogen in reactor got optimal value when the ratio of loading rate from 1.5 – 2.5 kg BOD †TKN/kg sludge/day.
The effect of the building blind area heat insulation on heat losses through the floor on the ground
Authors: Malyavina Elena , Gnezdilova Elizaveta 
Published: July 2020

Abstract
The relevance of the problem under studying is the appearance of non-traditional heating insulation structures of the floor on the ground, that can not be subject to calculations of heat losses using the existing methods. The purpose of this article is to find out the average characteristic heat transfer resistances in the design zones adopted in the Russian Federation for thermal protection of the floor on the ground by heat insulating the blind area of the building. Factors essential for possible elimination of condensation on the junction of the floor and the exterior walls were evaluated, as well as the possible maintenance of the floor temperature at the border of the serviced area not below specified values. The method of investigation is the annual calculation of unsteady thermal regime of flooring with the soil massive by finite difference method according to the implicit scheme. As the results we can state a significant impact of the type of soil on the heat loss through the ground floor, an insignificant impact of the width and thickness of the insulated building blind area. The most critical for the possibility of using the blind area heat insulation is the practical inability to provide acceptable temperatures of the floor at the wall-to-floor junction and on the border of the serviced zone. The main conclusion is that the heat insulation of the building blind reaches its goals at the room temperature of 10 °C. But it needs additional small heat insulation of the floor on the ground itself at a room temperature of 20°C and 30°C.
Upgrading of industrial wastewater technique by pressure flotation
Authors: Yantsen Olga , Gerasimov Vladislav , Storozhev Alexey 
Published: July 2020

Abstract
The aim of the study is to develop a technology for the treatment of industrial wastewater by means of a pressure flotation unit. The modernized unit of pressure flotation with various feed of water-air mixture was designed and constructed on the basis of the review of scientific and technical literature. The tests with different variations in the supply of water-air mixture to the unit were carried out in order to improve the quality of treated wastewater and, as a result, to the reduction of environmental damage. We carried out a comparative analysis of each variant in terms of the quality of treated industrial waste water and we identified the most appropriate variant for various technological treatment schemes. All results of the research considered we offer the automation of this device. The purpose of automation of the pressure flotation unit was to increase the efficiency of the used equipment, to maintain the stability of the unit, to obtain information on all the processes of industrial wastewater treatment, as well as to prevent an emergency situation.
Phosphate removal from wastewater using reinforced feed material at the tertiary treatment stage
Authors: Ruzhitskaya Olga 
Published: July 2020

Abstract
In recent years, eutrophication processes have posed a serious threat to water bodies. As a result of excess inputs of nutrients (nitrogen and phosphorus) from drainage basins, natural water quality deteriorates, which is usually accompanied by changes in the water bodies ecosystem structure. The increased concentration of nutrients leads to the rapid development of blue-green algae, reduced dissolved oxygen, fish-kill, coastal zones overgrowth, treated water processing complication. The article provides relevant information in the field of phosphate-removing wastewater treatment. The article presents advanced chemical and physical-chemical methods of phosphate-removing wastewater treatment. The article presents the results of the research on phosphate-removing wastewater treatment methods using iron-bearing feed material. The evidence of physical-chemical nature of deep phosphate-removing purification of water is presented. Deep phosphate removal is mainly due to physical-chemical processes of phosphate coagulation with ferrous ions, the source of which is the metal in the feed material, which is subjected to processes of electrochemical corrosion. When the biofilm loading becomes overgrown, the contact of the metal surface area with water decreases and the purification effect decreases. After regeneration of the load, the efficiency of phosphate removal increased to its previous level. Using the method of deep phosphate removal from domestic wastewater, with the help of reinforced feed material, at the tertiary treatment stage the required efficiency of phosphate removal can be achieved, however, there is a high consumption of metal in the feed material.
Presentation of climate information for calculating annual energy consumption by air conditioning systems
Authors: Malyavina Elena , Van Luong Pham 
Published: July 2020

Abstract
In the present work, climate models were presented, which are intended for calculating energy consumption of air conditioning systems, spent on processing the outdoor air to supply it to the room as a supply air, and on the assimilation of heat from external and internal sources. Currently, the number of buildings is growing, in which the bulk of the heat surplus is made up of internal heat. Therefore, for such buildings, a climate model is needed that contains only data on the repeatability of combinations of temperature and humidity of the outside air. Such a model is a probabilistic-statistical climate model. To calculate the energy consumption of air conditioning systems in rooms with a load formed due to heat transfer through external building envelopes and the direct penetration of the heat of solar radiation, we need a model that contains not only the mentioned probabilistic characteristics, but also changes over time combinations of climate parameters. Such a model is a reference year. The article presents data on the development of a reference year for the city of Hanoi and shows that when assimilating only internal heat surpluses it is advisable to use a probabilistic-statistical model, that provides a much more accurate result.
Transportation and surface runoff treatment
Authors: Govorova Zhanna , Zaripov Roman , Popov Pavel , Govorov Vadim , Kantakov Roman 
Published: July 2020

Abstract
Surface water runoff are characterized by specific physicochemical composition, which depends on the area of water disposal. Surface runoff in Russia and other foreign countries characterized by high concentration of suspended solids, petroleum products, high chemical oxygen demand and etc. This article provides data about foreign and Russian compact filters. Filters are installed in the water receiving sumps of the storm sewage system. Analysis of efficiency of different filter construction has been conducted. As a result of this analysis it is determined, that its efficiency, purification capacities and resource are highly limited, while its operating costs are quite high. Stationary surface runoff treatment plants are more reliable, and allow to reach purification level, which is required to dispose surface runoff into water objects. Composition of treatment plants depends on amount of surface runoff and transportation conditions. This article provides results of visual observation of sewer collectors condition, which are used to transport surface runoff to treatment plants, and its common defects. This article also provides results of study of structure and composition of sediment, which is found inside the sewage collector. It is determined, that size of sediment particles equals to 3-4 mm and its density - 2.3 g/sm3. Main elements of the sediment are silicon and oxygen, but there are aluminum, calcium and sodium additives.
Application of Geographical Information System in Environmental and Economic assessment of Run-of-river Hydropower in Central Vietnam
Authors: Lan Huong Nguyen , Thi Viet Nga Tran 
Published: July 2020

Abstract
Conventional hydropower exploitation includes building large dams and reservoirs would pose significant impact to the environment. Recently there is trend to switch from building large hydropower plant to small and medium size, particular run-of-river hydropower plant. This study assesses the feasibility of installing run-of-hydropower scheme in the Vu Gia Thu Bon river basin with regards to the environmental and economic impact. The analysis was performed using GIS to identify the location of power plant that might have environmental constrains. The economic payback of each power plant was calculated and spotted on the digital maps. The methodology proposed in this study could be helpful for decision-makers in the preliminary identification of the most suitable locations to install run-of-river plants in the Vu Gia Thu Bon river basin.
Initial stress state at installation of a single-layer lattice dome due to errors of its assembly
Authors: Lebed Evgeny 
Published: July 2020

Abstract
The paper presents the results of the numerical modeling of the assembly process of single-layer lattice domes with respect to random deviations in lengths of individual bars which was performed with a special purpose software SBORKA developed by the author. Modeling of the installation process of the dome frame was performed by sequential calculation of the coordinates of its nodes through simulation of the connection of individual bars in these nodes. The inaccuracies of the bar lengths used were random variables with a normal distribution law. Due to errors in the length of the bars, the actual geometric scheme of the dome frame is distorted in relation to the design scheme. To obtain objective data on such distortions, numerical computer modeling was performed repeatedly with statistical processing of the results obtained. The sequence of assembly of the dome frame was chosen such that the largest number of different types of rods were used. Distortions in the geometric scheme of a single-layer lattice dome do not allow its frame to be installed simultaneously on all support nodes. First, the dome frame is installed only on three support nodes, and then due to deformation under its own weight, the remaining support nodes are included in the work. This deformation of the dome frame leads to the appearance of initial stress state in the bars. In this research, computer static analysis of a single-layer lattice dome was performed for the action of the self-weight load of its frame. The analysis was made taking into account the sufficiency of the load to exhaust the existing gaps in the support nodes. Based on the results of these calculations, the initial stress state in the bars of the dome frame are obtained, which should be taken into account in the analysis and design of the structure.
Dynamic stress state of underground pipelines at junctions
Authors: Ismoilova Sabida , Loginov Pavel , Khamidov Saidjon , Akbarov Nodirbek , Kumakov Jakhongir X 
Published: July 2020

Abstract
A one-dimensional statement of unsteady wave problem of a longitudinal monochromatic wave propagation and reflection from a rigid stationary barrier to which an underground pipeline abuts is given. The linear viscoelastic Eyring model, which describes limited creep and limited relaxation, is taken as the pipeline strain law. Eyring model allows us to describe the behavior of underground steel and polymer pipelines under dynamic loading. The problem is solved numerically using the theory of characteristics, followed by the finite difference method in an implicit scheme. Numerical solutions obtained in the form of dependences of plane wave parameters: longitudinal stress, velocity and strain for fixed sections of the pipeline are analyzed in the paper. An analysis of changes in these wave parameters shows that at high frequencies of dynamic load generating the wave, the stress amplitude in the pipeline increases by two or more times compared to the load amplitude. This is due to the superposition of incident and reflected waves in the pipeline and to a high loading rate of the pipeline. At low frequencies of dynamic loading, such an increase is not observed due to the low loading rate. The obtained numerical solutions allow choosing the statement of problems on dynamic stress state of an underground pipeline depending on the frequency of incident wave. It is shown that the greatest longitudinal stress in an underground pipeline arises in points (sections) close to its connection with a rigid stationary solid body.
Shear waves around an underground pipeline
Authors: Sultanov Karim , Khusanov Bakhtiyar , Rikhsieva Barno 
Published: July 2020

Abstract
A two-dimensional axisymmetric problem of shear wave propagation around an underground pipeline under longitudinal motion of the pipeline is solved numerically. Due to the significant difference in pipeline and soil rigidity, the underground pipeline is considered to be a rigid undeformable body and the soil medium around the pipeline is modeled by a viscoelastic law in the form of a generalized Eyring model. To solve the problem, the finite difference method modified by the Wilkins difference scheme was used. On the contact surface of the underground pipeline with soil, the conditions of complete cohesion are fulfilled. Changes over time in shear stress, velocity and soil particles motion in the direction of pipeline axis in fixed sections of soil are obtained. The process of soil displacement around the pipeline at fixed time points is shown. The attenuation of the maximum values of wave parameters in soil in the radial direction with distance from the underground pipeline was detected. The maximum value of shear stress was reduced by three times compared with the value of shear stress at the contact with the pipeline. The effect of the load action time and unloading waves on the wave parameters in soil around the underground pipeline is also obtained. Based on the results of problem solution, the viscoelastic diagram “shear stress - shear strain” is obtained. The results obtained make it possible to determine the mechanism of formation of the stress state and soil reaction to the underground pipeline, which can be used in strength and reliability calculation of the pipelines.
Strategy for the evolutionary optimization of reinforced concrete frames based on parallel populations evolving
Authors: Tamrazyan Ashot , Alekseytsev Anatoliy 
Published: July 2020

Abstract
An algorithm has been developed for optimization of reinforced concrete frames with the possibility of forming a structure with a subsequent selection of reasonable section sizes and reinforcement for it. A modified genetic algorithm is used as the main search tool. The overall optimization process is divided into two stages. At the first stage, the topology is synthesized by randomly excluding groups of structural members as well as changing the position in space of the remaining groups. At the second stage, local parallel evolving genetic algorithms are performed for the formed topologies. With a common set of variable parameters, the migration of individuals between parallel populations is not allowed. An example of optimization of the multi-story building frame is considered.
The change in mass of insulating materials in the Vietnamese climate conditions
Authors: Nam Nguyen Tien , Grabovy Petr , Kazarnovsky Valery 
Published: July 2020

Abstract
In article obtained in laboratory experiments, water absorption characteristics and evaporation of water from the insulation materials to determine their weight change in tropical climates with the following characteristics: high temperature and humidity, a large number of medium and monthly rainfall seasonal rains lasting 6 months. Thus, the obtained results may be used to repair wall enclosing parts in the Vietnam construction industry. The characteristics of waterproof, moisture resistance, water evaporation, biological stability in insulation materials, which are used in the thermal protection of buildings in Russia and in the world. Evaluation experiments were performed on the characteristics of water absorption and water evaporation of heat-insulating materials (mineral wool, polyfoam, extruded polystyrene) in the laboratory in three situations: the location of samples on the surface of the water, drowning of samples in water and evaporation water from water-saturated samples. These tests simulate the impact of rainfall on the insulation material and evaporation of water from the insulation material during a certain time period (e.g., during assembly or during operation, when the protective layer is damaged). The experimental results show the dependence of saturation insulation from direct contact with water in his drowning conditions and arrangement of heat-insulating materials on the water surface. In addition, the rate of evaporation of water in the water depends on the amount of thermal insulation material and its characteristics. Based on the results of such experiments, it is possible to make a choice of types of insulating materials suitable for Vietnamese climatic conditions.
Multi-criteria optimization of reinforced concrete beams using genetic algorithms
Authors: Tamrazyan Ashot , Alekseytsev Anatoliy 
Published: July 2020

Abstract
A strategy for finding optimal solutions for beam reinforced concrete structures according to several criteria has been proposed. The analysis and systematization of the optimization objectives for reinforced concrete framed systems is performed. To solve the problem, a modified genetic algorithm is used, which involves the selection of design options in a single iterative process into several databases containing solutions for each target criterion. When forming the current set of solutions, the migration of the best options from any base under consideration is allowed. As a general criterion of optimality, the J. Nash equilibrium principle is considered for penalties under failure to comply with constraints in relation to reinforced concrete structures.