bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of mechanical safety of cost-optimized reinforced concrete structures
Authors: Tamrazyan Ashot , Alekseytsev Anatoliy 
Published: January 2021

Abstract
The methods for evaluation of the optimality degree and the level of mechanical safety of design solutions are considered as an example of a reinforced concrete frame. Integrated safety margins of rigidity and stability are introduced, which are calculated according to the inherent structural sections formed as a result of discretizing the object into finite elements. The methods provide for the possibility of such an evaluation for relatively simple structures and without the finite element method. Using the example of a reinforced concrete framed stack, an evaluation of four design solutions obtained for various operating conditions by the normal designing and using an adapted genetic algorithm is illustrated.
Safety of engineering systems of buildings with limited heat supply
Authors: Rafalskaya Tatyana 
Published: January 2021

Abstract
In case of emergencies in large heat supply systems, the water temperature in the supply line of the heat supply system is reduced. It is necessary to determine the acceptable duration of the heat supply system during an emergency, taking into account the thermal accumulation of the external fencing and variable water consumption in the hot water supply system. A study was made of the operating modes of the heat supply system in conditions of emergency heat supply from the CHP. The factors affecting the thermal regime of buildings with external fences of various constructions with limited heat supply are considered. A method has been developed for calculating the cooling rate of the inner surface of the outer fence and the temperature on this surface at a given point in time. Calculated dependencies are obtained to determine the acceptable duration of the heat supply system with limited heat supply. Application of the developed methodology can increase energy efficiency and contribute to the energy saving of buildings in the event of emergencies in the heat supply network.
Analysis of the features of activated sludge biocenosis in aeration tanks at wastewater treatment plants
Authors: Manukhina Veronika 
Published: January 2021

Abstract
Application of the method of microscopy and visual analysis of the composition of activated sludge in aeration tanks. The advantage and ease of use of the microscopy. Detection of violations in the biocenosis of activated sludge at early stages. Characteristics and diversity of microorganisms in activated sludge. Consequences of accidents at sewage treatment plant.
Social-oriented approach to street public spaces design
Authors: Danilina Nina , Vlasov Denis , Teplova Irina 
Published: January 2021

Abstract
Global challenges for urban development determine the need to develop new approaches to urban environment design aimed on smart and sustainable cities. City streets become centre of human life and places where many public functions are concentrated. Thats why nowadays the issue of street function relates non only to its transportation use, but also to the development of public interaction and a new progressive approach to the social-oriented design of the urban environment with the involvement of the population is becoming a great demand. The article offers a social-oriented approach to the functional zoning of public spaces along city streets to create comfortable and safe environments and to ensure the effective land use of the linear street space resource. The approach is based on the concept of demand and supply relative to territorial assessment of various public functions. It is proposed a model of functional planning of the territory and social space depending on the users needs. The proposed approach to urban development was tested for example in Moscow streets.
Determined of Equivalent Fixed Depth in the 3D Frame
Authors: Nguyen Xuan Bang , Thanh Dinh Viet 
Published: January 2021

Abstract
The paper presents the results of solving the problem of identifying the equivalent depth of the linkage of the frame -pile structural system. The computational model of the problem is a frame -pile structural system in the form of three-dimensional frame, linear elastic deformation, pile -soil link is replaced by a hard restraint (fixed) with equivalent restraint depth. The problem is solved by the method of penalty function to combine with the finite element method. Examples of numerical calculations show that models, algorithms and calculation programs can be trusted and acceptable.
Mathematical modelling of torsional vibrations of the three-layer cylindrical viscoelastic shell
Authors: Khudoynazarov K , algashev B F Y , Mavlonov T 
Published: January 2021

Abstract
The paper considers a circular cylindrical three-layer shell of arbitrary thickness from a viscoelastic material. It is believed that it consists of two outermost bearing layers and a middle layer between them, the materials of which are generally different. The problem of unsteady torsional vibrations of such a shell with rigid contact between the layers is formulated. Proceeding from the assumption that there is a rigid contact between the layers, the dynamic and kinematic contact conditions of the problem are formulated. On the basis of exact solutions in transformations of the three-dimensional problem of the linear theory of viscoelasticity for a circular cylindrical three-layer shell, a mathematical model of its unsteady torsional vibrations has been developed. The proposed model includes the derivation of the general equations of torsional vibrations of the shell with respect to two auxiliary functions, which are the main parts of the torsional displacement of the points of some intermediate surface of the middle layer of the shell. Along with the equations, an algorithm for calculating was created that allows, based on the results of solving the equations of vibration, to unambiguously determine the stress-strain state of the shell and its layers in their arbitrary sections.
The application of simulation modelling in making operational decisions in construction
Authors: Sborshikov Sergey , Vvedenskiy Roman , Markova Irina 
Published: January 2021

Abstract
The emergence of new organizational methods such as controlling, including strategic and operational-production, is a response of investment and construction activities to new challenges generated by the development of science and technology, as well as socio-economic conditions. The need of society, as a kind of aggregated customer of capital construction projects, is to reduce the cost, duration of their construction, improve the quality of buildings and structures. Achieving such results is possible through the use of new materials, equipment, technologies. However, the conditions for the construction of a specific facility, the current operational situation are conditioned by the presence of disturbing influences of both technical and managerial nature, and which must be stopped in time and, if possible, prevented. Thus, a toolkit is needed that involves the implementation of the functions of analysis, monitoring, but also the development and even adoption of operational technical and managerial decisions. It is on these principles that operational and production controlling is based. The adoption of appropriate tactical decisions is the central point in the organization of operational and production controlling in construction production, and also the fact that the real tasks of organizing construction are not always fully solved analytically. One of the promising ways can be the use of optimization methods in combination with simulation models and the provisions of the theory of experiment planning. The article proposes to consider the use of simulation modeling when optimizing the calendar schedule for the implementation of a complex of construction and installation works, carried out in the process of operational and production controlling.
Model of rainwater runoff formation on the surface of complex topography
Authors: Kuchkarova Dilarom , Achilova Dilnoza 
Published: January 2021

Abstract
The article discusses the issues of water disposal, with curvilinear coatings. The tasks of calculating rainfall at industrial sites and urban areas of complex topography arise in the process of modern urban construction.
Modern requirements for design quality necessitate accurate calculations of rainfall, location, size and number of drainage devices. The article points out the existence of a gap between the practice of calculating rainfall runoff and the theory of mathematical modeling of runoff. Also, modern mathematical models of the formation of rainfall are analyzed. A runoff model is proposed that provides a compatible consideration of the relationship between flow rates and water volumes in the area with the runoff genetic formula. The catchment area is torn by a network of lines of greatest slope and isochrones. For each elementary site, the ratio of the water balance is determined.
The continuity equation for the catchment is obtained. For the numerical implementation of the runoff model, a difference scheme is used. Specific programs are provided for the developed algorithms.
A computer program in the MatLab language has been developed for the proposed runoff model. The program has been tested at specific facilities.
Safety and risk categories of water reservoir hydrosystems
Authors: Yangiev Asror , Gapparov Furkat , Adjimuratov Dilmurat , Panjiev Sherzod 
Published: January 2021

Abstract
The article provides an analysis of accidents and their main causes in existing reservoir hydro-systems in the world. Besides, the article presents the diagram for accident causes in reservoirs. Risk category assessment is given for Langar, Kizilsuv and Kalkamaflood-reservoirs. According to available data from the Congress on large dams, currently there are no regulations on risk assessment for water reservoir hydro-systems in Uzbekistan. In addition, major security challenges and recommendations are presented to improve the operation of water reservoir hydro-systems.
Hydrodynamic effects of the flow on the slab of the stand in the presence of cavitation
Authors: Bazarov Dilshod , Vatin Nikolai , Bakhtiyor Obidov , Oybek Vokhidov , Rakhimov Ashraf , Akhmadi Makhfuz 
Published: January 2021

Abstract
This (article) work is devoted to one, relatively unbalanced issue of the dynamics of hydraulic structures - the determination of hydrodynamic loads on the slabs of a high-pressure spillway in a cavitating flow in the presence of erosion-free energy absorbers.
Working on the implementation of these studies, the authors simultaneously studied in laboratory pulsation loads on a real structure - elements of the downstream spillway devices, below – the Kafirnigan hydroelectric complex.
Improvement of hydraulic accounting of water resources in irrigation systems using geoinformation systems
Authors: Qosimov Jakhongir , Nasritdinova Umida , Nasritdinov Axmadjon 
Published: January 2021

Abstract
The work presented in the article directly determines the role of geoinformation systems in irrigation and land reclamation based on today’s requirements. At the same time, the results of analysis and evaluation of existing experimental and theoretical researches lead to the conclusion that modern mechanisms of accounting of water distribution in irrigation systems based on the analysis programs for high resolution of satellite images are not developed. from theoretical and practical points of view to GIS to the object. Therefore, studies on the use of DIO in water accounting are rare. Many studies in this area are devoted to land use and classification.
Study of irrigation characteristics and improvement of irrigation techniques using interpolymer complex-based anti-filtration screen
Authors: Gadaev Nodir , Ahmedjonov Dilmurod , Amanov Bakhodirjon , Muxammadeva Matluba , Ergashev I 
Published: January 2021

Abstract
In the world, special attention is paid to targeted research on water resources management and efficient use of irrigation water resources. In this regard, one of the main tasks is to improve the technique of irrigation of fields using cheap chemical and technical means, the development of new methods of water-saving irrigation, the development of the theory of water-saving technologies in irrigation of fields. In this regard, the use of inexpensive interpolymers to reduce soil composition and irrigation water infiltration is of particular importance.
Shock wave velocity in two-phase pressure flow
Authors: Jonkobilov Ulugmurad , Jonkobilov Sobir , Rajabov Ulug’bek , Bekjonov Rozisher , Norchayev Abdulla 
Published: January 2021

Abstract
The article is devoted to the study of the propagation velocity of the rarefaction wave and the compression wave, taking into account the two-phase (water + air) flow in the long pressure pipelines of pumping stations. Hitting speed is the main parameter of water hammer. Water hammer poses a danger to the normal operation of the main equipment of stations, control and measuring equipment, control devices and pressure pipelines. When establishing the strength indicators of pressure pipelines, it is necessary to make an accurate calculation of the shock wave speed, taking into account the dosed amount of not dissolved air in the water. The classical theory of water hammer is based on the gamogenic model and does not take into account air in the liquid. This circumstance leads to a decrease in the accuracy of calculating the velocity of the shock wave and water hammer. The article presents the results of analytical studies of the shock wave velocity, taking into account the two-phase pressure flow. At the same time, an analytical method for calculating the velocity of the shock wave is proposed. The results of the proposed technique are in good agreement with the graphical solutions of this problem and with experimental data.
Non-eroding speed of water flow of channels running in cohesive soils
Authors: Eshev Sobir , Latipov Shakhboz , Qurbonov Azizali , Sagdiyev Jasur , Berdiev Mustafo , Mamatov Nurbek 
Published: January 2021

Abstract
The authors of the article, on the basis of laboratory experiments, describe the kinematic the structure of the erosion rates of the water flow in the conditions of non-cohesive soil lying in the peceidal canals. A methodology for conducting laboratory experiments and analysis of the results tov research. Dependencies are proposed for determining non-eroding water flow rates taking into account the occurrence of the slopes of the trapezoidal canal.
System for ensuring the detection and elimination of fires in the building of the hydroelectric power station
Authors: Shaazizov Farrukh , Shukurov Diyor , Shukurov Elyor 
Published: January 2021

Abstract
The aim of the work is to develop theoretical and methodological foundations for predicting the likelihood of fires in the premises of hydroelectric power plants, as well as compiling algorithms for monitoring the fire safety system, the “Serviceability control” technological process and the “Fire” technological process.
In the course of the work, theoretical studies of methods for assessing the safety of power generating enterprises in the “man -machine -environment” system and ways of occurrence of emergency situations at power plants were carried out.
The analysis of methods for assessing the safety of power plants in the “man -machine -environment” system is considered and the analysis of the ways of occurrence of emergency situations at power plants, as well as the types of fires and the peculiarities of their detection in the premises of the hydroelectric power plant. And an attempt is made to solve the problem of super-early detection of fires and fires in the system under consideration.
The theoretical and methodological foundations for predicting the probability of fires depending on the operating modes of systems, devices and equipment and a compiled model of a fire hazard monitoring system are given.
Prediction of thermal stress in a concrete gravity dam
Authors: Aniskin Nikolay , Nguyen Trong Chuc 
Published: January 2021

Abstract
Temperature is one of the main factors affecting gravity concrete dams. The effects of many temperature factors on the gravity concrete dam cause additional deformations and tensile stress, as a result, thermal cracks appear. In order to determine the predictive model of temperature regime and thermal stress states in gravity concrete dams is a difficult problem. Because there are a large number of factors that influence temperature regime and thermal stress in the dam during construction and operation. This paper presents the results of numerical modeling of the temperature regime and thermal stress state of the Ban Lai roller-compacted concrete gravity dam (Lang Son province, Vietnam) 56 m high. The model was created using the Midas software package and can evaluate the work of the structure under the influence of temperature during construction and operation phases. The results obtained were taken into account when designing the structure and can make appropriate recommendations.
Improvement of water accounting for irrigation systems
Authors: Fatxulloyev Alisher , Gafarova Aziza , Hamroqulov Jasur 
Published: January 2021

Abstract
The use of water metering devices operating on hydraulic energy for open canals of on-farm irrigation systems, the error in measuring water flow is substantiated. In addition, the article provides an analysis of the water metering in main canals, the possibility of using hydraulic structures. In modern conditions of agricultural development, a special role is assigned to hydro-reclamation, as one of the main factors that guarantee high stable yields of agricultural crops. At present, when water has become an expensive commodity, for the rational and efficient operation of irrigation systems, operational and objective water metering must be carried out, and hydraulic structures on the canals must ensure the supply of specified costs. To control the consumption of water in open canals of irrigation systems, mobile and stationary gauging stations are used -water metering points.
Ploughing quality and energy consumption depending on plough bodies type
Authors: Lobachevsky Y P , Liskin I V , Panov A I , Aldoshin N V , Plyaka V I , Lylin N A 
Published: January 2021

Abstract
Experimental determination of ploughing quality and energy consumption carried out on loamy soils most common for the arable lands in European part of Russia. The field tests done for three standard types of mouldboard body surfaces: cultural, semi-helicoidal (cylindroid) and helicoidal. Results shows that bodies with cylindroid mouldboard surface had better soil crumbling against cultural (digger) body surfaces. Helicoidal bodies supplied better quality of soil layer turnover than cultural and semi-helicoidal ones. Designed plough construction allowed change ploughshares installation angles relative to the furrow line from 25 to 55°. Optimal ploughshares angle to the furrow line obtained 45…50°. The traction resistance force of the plough equipped with helicoidal bodies was measured 6…8% lower than cultural bodies and 3…4% lower than cylindroid ones at tractor speed 2.5…3.0 m-s-1.
The innovative solar energy conversion technologies: solar convective-vortex power systems
Authors: Solovyev Alexander , Solovyev Dmitry , Shilova Liubov 
Published: January 2021

Abstract
The article provides an overview of the existing problems arising in the conversion of radiant energy into the energy of currents, as well as in the transformation of electrical energy in solar convective-vortex power plants. On the practical example of a pilot industrial solar aerobaric power plant, the possibility of implementing solar-convective-vortex power systems is illustrated. As a result of a comprehensive analysis, factors have been determined that allow creating optimal conditions for controlling the processes of concentration of thermal energy of solar radiation into the power of tornado-like flows.
Comparison of adsorbing NO2 in boron and phosphorus doped graphene/ZnO heterojunction
Authors: Jin Yanxin , Ding Jijun , Chen Haixia 
Published: January 2021

Abstract
As a new two-dimensional material, the adsorption properties of the graphene-like ZnO monolayer (ZnO-ML) have been investigated in our previous work. In this paper, the heterojunction are constructed using ZnO-ML and doped graphene. The electronic and adsorption properties of the boron doped graphene/ZnO (B-G/ZnO) and phosphorus doped graphene/ZnO (P-G/ZnO) heterojunction are investigated based on density functional theory (DFT). Firstly, the B-G/ZnO and P-G/ZnO heterojunction are constructed and their structures are optimized. Then, according to the comparison of adsorption energy and adsorption height, the most stable adsorption configurations are obtained. They are the T and TO site corresponding to the B-G/ZnO and P-G/ZnO heterojunction, respectively. Finally, in order to further explore the adsorption mechanism between the heterojunction and NO2 molecule, the band structure, density of states (DOS) and the partial density of states (PDOS) in B-G/ZnO and P-G/ZnO heterojunction are compared. These results can provide more theoretical support for the adsorption properties of heterojunction based on the ZnO-ML.
Recent progress in two-dimensional Ruddlesden–Popper perovskite based heterostructures
Authors: Fang Chen , Wang Haizhen , Li Dehui 
Published: January 2021

Abstract
Two-dimensional (2D) perovskites have recently received increasing attention due to their enhanced environmental stability, layered nature and excellent optoelectronic characteristics. Particularly, the layered nature of 2D perovskites allows to conveniently integrate with other materials to form heterostructures, which can extend device functionalities and improve the performance of the corresponding optoelectronic devices. In this review, we aim to provide a comprehensive presentation of the recent advances of 2D perovskite based heterostructures. We will first give a brief overview on the structure and basic optical properties of 2D perovskites. Then we will focus on 2D perovskite based heterostructures including 2D/2D perovskites, 2D/three dimensional perovskites, 2D perovskites with 2D layered materials as well as 2D perovskites with other optoelectronic materials. Finally, we will outline the current challenges and future research directions in the field of 2D perovskite based heterostructures.
Preparation of recyclable corn straw fiber as oil absorbent via a one-step direct modification
Authors: Shi Yanlong , Feng Xiaojuan , Yang Ruihua 
Published: January 2021

Abstract
Accidental marine oil discharge causes severe environmental pollution and thus remediation is essential. However, the removal and recycling of the spilled oil using economical and highly efficient methods are still major challenges. In this work, an oil absorbent of corn straw fibers (CSF) were prepared via a one-step direct modification with hydrophobic octyltrimethoxylsilane (OTS). With the surface modification, the CSF exhibited both superhydrophobicity and superoleophilicity, and the contact angles of water and oil on the as-prepared samples were 156 ± 1° and 0°, respectively. Owing to the oleophilicity and hydrophobicity features of the CSF, it could be used to selectively absorb oil in water. The adsorption capacity of the as-prepared absorbents for diesel oil, the recyclability, and the reaction mechanism between OTS and the CSF were investigated in detail. The oil absorbent could still remain superhydrophobic even after eleven successive cycles of oil-water separation. With the characteristics of easy biodegradability, durability, and recyclability, as well as the facile procedures involved, oil absorbent of CSF prepared by direct OTS-modification is expected to be used for oil spill cleanup and recovery.