bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using of particle swarm optimization (PSO) to addressed reliability allocation of complex network
Authors: Abdullah Ghazi , Haddi Hassan Zahir Abdul 
Published: November 2020

Abstract
This paper focuses on the reliability of complex system that has been measured as a complex system using minimal paths. The reliability of this system has been assigned to research the possible approaches of the assignment reliability values based on reducing the total cost of this method. The results originally included:
(i) Three cost functions were used to measure the cost of the complex system: First, the exponential behavior model with the feasibility factor model. Second, the exponential behavior model. Third, the logarithm model.
(ii) The reliability of every component of the system was calculated using Particle Swarm algorithm to solve the problems of optimizing the given reliability of the complex system.
The Effect of Diyala Tributary on Ecological Factors of Tigris River
Authors: Nashaat Muhanned R. , Muftin Fatema Sh. , Abbas Enaam K. , Ali Eman H. 
Published: November 2020

AbstractThis study was conducted to investigate the effects of the Diyala Tributary on the physical – chemical factors of the Tigris River. A water sample was collected monthly from five sites. Site 1 was located on the Tigris River before joining the Diyala with Tigris River, site 2 was located on Diyala River, site 3 was located on the Tigris River after 500m from joining area of Tigris with Diyala River, Finally site 4&5 was located 3, 5 Km of site 3 respectively downstream Tigris River. The results of this study illustrated that the variations in the values of turbidity and the total suspended solids in the Tigris River and Diyala Tributary were not sharp, whereas there was clear effect of Diyala Tributary by raising the values of the electrical conductivity, salinity, TDS, BOD5, total hardness, bicarbonate, sulphate of the Tigris River. Also there was an increase in the phosphate and nitrate concentrations with depletion of dissolved oxygen at site 2 which located on Diyala Tributary that affected on Tigris River significantly.
Microplastic Contamination of Surface Sediment of Euphrates River, Iraq: A Preliminary Study
Authors: Kadhum Safaa A. , Abed Salwan Ali , Ewaid Salam Hussein , Al-Ansari Nadhir , Naji Abolfazl 
Published: November 2020

Abstract
Microplastics pollutants in sediment have been notified in freshwater and estuaries from different countries. However, microplastics abundance, distribution, and polymer types in surface sediment from Euphrates River were reported for the first time. Microplastics were found in all sediment sites along the river, and abundance ranging from 29.6 to 120.0 particles/kg dry, with an average 86.7 particles/kg dry. Fiber particles were the most predominant form (57.1%), followed by films (29.6.2%) and fragments (13.1%). The polymers identified using Fourier Transform Infrared Spectroscopy (FTIR) which was dominantly polyethylene (44.1%), polyethylene terephthalate (35.0%) and nylon (20.2%). It is clear that the microplastics levels in sediment from Euphrates river were polluted and these data will be useful for manage and rehabilitation the Iraqi rivers to reduce possible microplastics pollution.
The impact of the formation conditions and properties of the water treatment plants sludge on its usage in the ceramic bricks production
Authors: Orlov A A , Belkanova M Yu , Lymar R K 
Published: November 2020

Abstract
Water treatment plants (WTP) sludge can be used in the construction industry. However, the composition and properties of WTP sludge are determined by the quality of water in the water source and the water treatment technology. At the same time, the technology for the manufacture of construction products requires a consistent quality of raw materials and reproducible characteristics of the finished products. In this paper, we studied the impact of a modifying add from WTP sludge on the properties of the clay composition and ceramic bricks. We used the WTP sludge formed in the fall and winter periods in the city of Chelyabinsk. The air-dry WTP sludge was introduced into the clay composition in an amount of 5-10% by mass. It is shown that the characteristics of the ceramic fragment are independent of the sludge collection season. It was found that the modifying add allows us to reduce the ceramics baking temperature by 50 °C without worsening the material baking index. The introduction of a 10% WTP sludge add helps to reduce the tendency of the air-dried brick to crack formation and accelerates the drying mode.
Peculiarities of hardening of an astringent system based on orthophosphoric acid and serpentine with an admixture of magnesite
Authors: Orlov A A , Chernykh T N , Zimich V V 
Published: November 2020

Abstract
The paper considers peculiarities of hardening of the non-burnt binder system – orthophosphoric acid – natural serpentine with an admixture of magnesite and brucite. The samples were hardened according to the regime: pre-soaking (55 °C, 40 minutes), which ensures the preservation of the viscous-plastic state of the composition during the carbon dioxide evolution, followed by isothermal aging (80 °C, 24 hours). Strength increases with raising the amount of reacted serpentine and decreases with raising the volume of the released gas. The presence of trisubstituted magnesium phosphate, responsible for the strength, was established. In the solidified system, amorphous silica and unreacted serpentine, brucite and magnesite were found. The strength can be controlled by changing the specific surface of serpentine and the ratio between orthophosphoric acid and serpentine. It is possible to obtain a stone with strength of up to 40 MPa on the basis of serpentine and orthophosphoric acid after 1 day of hardening, with a specific surface of serpentine 4000 cm2/g and an amount of orthophosphoric acid of 25 % of the mass of serpentine.
Improvement of fire protection of wood board and textile materials for premises with a massive stay of people
Authors: Vachnina T N , Susoeva I V , Titunin A A 
Published: November 2020

Abstract
In premises with a massive stay of people according to the standards, materials with reduced combustibility should be used. Cellulose containing materials are fire hazardous. The article presents the results of a study of indicators of materials with combustion retardants for rooms with people staying – textile fabrics, chipboards. The effect of flame retardant additives on the weight loss of samples of wood boards under fire exposure was studied. The influence of the type and duration of impregnation to reduce the combustibility and drying temperature of the impregnated textile materials on the time of their flame burning is investigated.
The Structure and Properties of Hardened Cement Paste with Modifiers
Authors: Trofimov B Ya , Mahmudov A M 
Published: November 2020

Abstract
Currently, the durability of concrete is normalized by indirect indicators-the quality of the materials used, reinforcement and additives, the properties of the concrete mixture and its degree of compaction when molding reinforced concrete structures, the duration and parameters of concrete care. Regulatory documents, depending on the operating environment, regulate the maximum allowable value of W/C, the minimum allowable consumption of cement and the class of concrete for compressive strength. The main structural element of concrete is cement stone, the products of cement hydration provide its adhesive and cohesive properties and form a concrete conglomerate. Low basic calcium hydrosilicates form a cement gel-the densest and most durable component of cement stone. Modification of cement stone with water-reducing additives and microsilicon contributes to the formation of hydrosilicate phases in the form of an uncrystallized gel, a weakly crystallized gel-like C-S-H (I) phase with a ratio of C/S=1,1-1,3, and individual inclusions of calcium hydroxide are observed.
Measurement of crack growth speed in concrete by acoustic emission and mechanics of damage methods
Authors: Perfilov V A 
Published: November 2020

Abstract
The article presents the results of research and experimental studies aimed at measurement of crack growth speed in concrete of different types and composition. The study included complex methods to measure the parameters of concrete destruction under the impact of mechanic loads and aggressive factors. The experiments were performed using mechanics of damage methods and acoustic measurement of such parameters as acoustic emission gross counting and counting rate. The experiments resulted in regression equations showing change of acoustic emission gross counting depending on the speed of a specimen loading. Data on slow growth of cracks in heat-resistant concrete during heating up to 800°C have been obtained by acoustic emission and mechanics of damage methods. The performed studies and statistic processing of the obtained data allowed identifying that parameters of acoustic emission are directly related to the characteristics of mechanics of damage that reveals a considerable capacity of acoustic emission as a method for forecasting destruction of concrete.
Energy aspects of low-cycle fatigue of fibropolypropylene concrete
Authors: Korneeva I G , Pinus B I 
Published: November 2020

Abstract
The article discusses the issues of fatigue of conventional and fiber-reinforced cement-containing composites under low-cycle force impact that are adequate to the probable level of response of structures to background seismic manifestations. The response of the structures is analyzed as an oscillatory process whose generalized characteristic is the indicator of absorbed energy. The results of dynamic tests of prismatic samples with different levels of maximum stresses in the range Ro
crc-Rv
crc
and a zero-asymmetry coefficient are presented. The tests were carried out in a hard mode with a constant deformation rate of 0.04 mm/s and continuous cyclic recording of all internal resistance parameters. A significant increase in the fatigue life of cement-containing composites when reinforced with fibrillated short polypropylene fibers has been established.
The effect of mineral additives on foam concrete porosity
Authors: Bartenjeva E 
Published: November 2020

Abstract
Non-autoclave foam concrete is a promising material for low-rise house construction. It has been found that the addition of mineral additives allows to regulate the porous structure of non-autoclave foam concrete, at the same time the coefficient of thermal conductivity is reduced, density is reduced, and frost resistance is improved. The introduction of dispersed wollastonite and diopsid promotes the formation of conditionally closed pores, their volume increases by 47-49%. The introduction of wollastonite reduces the pore volume with a diameter greater than 0.1 μm by 2.34 times, the introduction of diopsid reduces it by 8.2%. It is noted that the addition of the examined additives enables to obtain closed pores with a glossy surface; it improves the performance characteristics of natural hardening foam concrete. According to the results of DTA (Differential Thermal Analysis) and XRFA (X-ray fluorescence analysis), a more complete hydration of cement is recorded, this fact can indicate the structural and modifying influence of additives as crystallization centers for newgrowths.
Methods for ensuring the required consumer properties for the construction of transport facilities in an accelerated time frame
Authors: Pulyaev I S , Pulyaev S M 
Published: November 2020

Abstract
The article discusses methods for providing concreting of transport objects without defects using the example of the construction of a bridge across the Kerch Strait. It is shown that through the use of modern calculation and analytical methods, it is possible to obtain high-quality structures and operational reliability under the conditions of the necessary construction pace. These methods are based on the construction of a thermophysical model of the processes that occur in hardening concrete during heating and cooling. The existing experience in the construction of similar facilities is also taken into account. The problem posed today is relevant in connection with the development of bridge building in our country. It has important economic and geo-political significance, and its solution is not possible without taking into account the temperature factor of hardening concrete. The proposed methods made it possible to ensure the required operational properties of the structures of this type and to withstand the established deadlines for the construction of the Crimean bridge. They can be used in the construction of other objects of this type.
Non-firing materials using clay soils
Authors: Zolotukhin S N , Andreev A V , Volokitin V P 
Published: November 2020

Abstract
This paper is concerned with the creation of non-firing technologies for strengthening clay soils in places with high groundwater level. The procedure for predicting the properties of composites by the activity of the surface of the fillers, carried out using modern diagnostic methods developed by the authors, has shown the effectiveness of its application on construction sites in the Voronezh region when building road bases and strengthening soils for buildings and structures. Using the defrosting effect on the construction site allows one to extend the seasonality of work on roads and construction sites and improve the quality of soil preparation due to the increased dispersion of unfrozen clay. The increase in the deformation modulus and strength of soil foundations was measured to be 2–3 times, as well as the decrease in porosity and the increase in soil density by 1.25 times, the decrease in moisture concentration over time due to the ability of the slag block to absorb moisture from the soil for a long time. Strengthening the soil by the broken stone materials formed during the demolition of buildings and structures allows one to create reliable homogeneous soil bases at construction sites in difficult hydrogeological conditions.
Imported products in construction activities: quantitative analysis of relationship (case of the Russian Far East)
Authors: Belousova A V 
Published: November 2020

AbstractThe article is devoted to assessing the dependence of the volume of construction work carried out in the region on products imported and used in construction. Econometric modeling is used as the main research method: dynamic models with distributed lag. For the case of the Russian Far East, estimates of the multipliers of imported products for regional construction are obtained. Multipliers show a low rate of decrease in the impact of imports on the dynamics of the volume of construction work: less than 1.7% per year. Therefore, for example, during the first eight years after the purchase of imported equipment, only 12.52% of its total long-term impact on the volume of construction is sold. The results can be used to determine the forecast dynamics of the volume of construction work depending on the actual and target indicators of imports of machinery and equipment.
Theoretical and experimental researches of operating properties of bitumen reinforced with carbon nanotubes
Authors: Zaporotskova I V , Bakhracheva Y S , Boroznina N P 
Published: November 2020

Abstract
The current level of economic development requires numerous road transport, which is constantly increasing, as a result, the roadbed is destroyed quite quickly. To maintain the durability of the road surface, various modifications are used to improve the physical properties. During the research, theoretical calculations and experimental confirmation of changes in the properties of bitumen when adding carbon nanotubes were carried out. Three concentrations of carbon nanotubes were tested: 0.1%, 0.01%, 0.001% in the bituminous mixture, as well as a reference sample without adding carbon nanotubes to compare changes in indicators. Based on the research carried out in the course of this work, it can be argued that the proposed method of strengthening the asphalt concrete coating by reinforcing the main component of the coating (bitumen) improves its physical and mechanical properties and, accordingly, increases the service life of the roadbed.
Study of the stressed state in the layers of the composite material of the construction element
Authors: Adegova L , Kolesova T , Kolokolkina E 
Published: November 2020

Abstract
Numerical analysis was used to estimate influence of orientation of composite material layers on strain changes in a constructive element. A finite element method was used to conduct a strain-stress state analysis. A cylindric shell with a radius of 300 mm, a height of 600 mm and a wall thickness of 1,56 mm was examined. The shell consisted of eight differently oriented carbon fiber layers, that were impregnated with epoxy resin. Plate Laminate type elements were used to imitate composite layers orientation and to create a model of cylindric shell walls. Lower base of the cylinder had rigid fasteners and the upper base was under external loading. During strain-stress state analysis of composite layers were examined following loading types: axial tension, bend, torsion, internal pressure. Numerical analysis revealed that tension distribution in layers of composites depends on layer orientation and the cylindric shell loading type. Moreover, this paper defines estimated fatigue life of the shell under pulsatory load. It was determined that characteristics of fatigue strength of the constructive element depend on loading type.
Rolling of a weld pad on a flat surface. One-dimensional problem
Authors: Brzhanov R T , Bulekbayeva G. 
Published: November 2020

Abstract
The analysis of modern welding methods shows that there are a number of factors in the weld pad, which together lead to a significant reduction in the wear resistance of the applied metal plating of the parts: a considerable variation of mechanical properties; Presence of inclusions and metallurgical defects; heterogeneity of structure and irregularity of surface solids in the length of the part; presence of unfavourable tensile stresses; reduction of fatigue of the parts on board; difficulty of mechanical treatment. The article solved the one-dimensional problem of non-responsive deformation of the weld pad at rolling and presented the main results of the work on the mathematical substantiation of the processes of rolling up the weld pad. One of the stages of the surfacing technological process was selected for the study, in particular, plastic deformation of the weld pad by rolling in a hard roller at elevated temperatures. Finishing processing by plastic deformation methods is accompanied by hardening of the surface layer, which is very important to increase the reliability of the parts. In the process of deformation, metals create a product shape and provide certain properties.
Study of stresses in plane truss nodes
Authors: Shabaldin A P , Kharinova N V 
Published: November 2020

Abstract
in this paper, the stress state in a plane truss node was studied in two ways: numerically using the finite element method and experimentally using the photoelasticity method. The finite element method was used to calculate plane truss model. Photoelasticity or polarization-optical method was used to research stresses of piezo-optical materials. The picture of interference fringe patterns in the model of a planetruss was obtained by the method of photoelasticity. Stresses were calculated with their help. The purpose of the work was compared with both methods. Fields of maximum tangent stresses were obtained in the sample plane using both methods.
Optimization of ventilation of an indoor ice rink by numerical simulation of air flows
Authors: Starkova L G , Doroshenko E K , Zotova D A 
Published: November 2020

Abstract
An important task in the design of objects with artificial ice cover is to provide them with a modern ventilation and air conditioning system, which allows maintaining the parameters of the air environment in the volume of the arena’s premises. A properly organized air exchange with an accurately calculated flow rate should ensure stable and comfortable air parameters on the roller for various zones. However, due to the complexity of the picture of thermal, mass transfer and air processes occurring during the operation of the ice arena, standard design techniques often do not allow to obtain the desired result. Therefore, at the present stage, it is extremely urgent to raise the quality of design of these objects, which can be done using the capabilities of the computer 3D-modeling method. At the moment, in the Russian Federation, modeling of air flows in the design of indoor ice platforms is used only in the construction of large facilities of national scale. This work presents a practical study on the possibility of using the method of numerical computer modeling to develop solutions to improve the ventilation systems of an existing facility of regional significance.
Methodology for calculating the ineffective diameter of thermal insulation
Authors: Anisimova E Yu 
Published: November 2020

Abstract
This article describes the results of energy efficiency analysis of various types of pipeline thermal insulation in a district heating system and equipment. The mathematical relations used in calculating the thickness of the thermal insulation for heat pipes and equipment are given. The concept of the critical value of the thermal insulation outside diameter of the heat pipe is described. An equation is presented that determines the ineffective thickness of the heat pipe insulation. A solution to this equation is proposed using numerical methods, namely, Newton’s method. The results of calculations of ineffective thermal insulation diameters for various parameters of the coolant, the diameters of the pipeline itself, and various heat-insulating materials are presented. The obtained data are analyzed. Recommendations are given for the correct selection and calculation of the thermal insulation thickness of district heating pipelines, as well as for the reconstruction of the existing ones.
Maintenance of heat stability of the heating system work in a structure
Authors: Novoseltsev B P , Zherlykina M N , Garmonov K V 
Published: November 2020

Abstract
We investigated the reasons of obstruction in elements of heating systems equipped with capacitive heating devices, which leads to an increase in hydraulic resistance, a decrease in the coolant flow rate, a decrease in the average surface temperature of the heater and a decrease in its heat transfer. We studied the decrease in the thermal conductivity of the pipeline walls of the heating system depending on the thickness of the sediment of solid particles on their surface. The analysis of the existing method of flushing heating system is carried out and its shortcomings are revealed. A better method for flushing single-pipe heating system hydraulically is proposed, which involves the following: to ensure effective flushing of capacitive heaters, it is proposed to supply clean water and to remove wastewater from different sides of the heating device. The application of the proposed method allows us to reduce the water consumption for flushing heating system, to reduce the flushing time, to exclude the transfer of solid particles to other elements of the heating system which improves reliability of its operation.