bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation model of thrust bearing with a free-melting and porous coating of guide and slide surfaces
Authors: Mukutadze M A , Mukutadze A M , Vasilenko V V
Published: July 2019

The method for the formation of an exact self-similar solution of the hydrodynamic calculation of wedge-shaped support (sliding bearing, guide bearing) with a porous coating of a slide, which operates in the presence of a lubricant and the melt of a guide coated with a free-melting metal cover. The analytical dependence for the molten guide surface is obtained on the basis of the equation of motion of a viscous incompressible fluid for a “thin layer,” the equation of continuity and the equation for the dissipation rate of mechanical power. In addition, the main performance characteristics of the investigated friction pair are determined. The assessment of the effect of the parameter caused by the guide melt and the parameter characterizing a porous layer on the slide surface on the bearing capacity and friction power is made.
Analysis of technological processes by processing of oil sludges with application of highly technological equipment for receiving high quality products
Authors: Bashirov V D , Balgynova A M , Ardak Merekekyzy , Sagitov R F
Published: July 2019

Any economic activity executed according to modern requirements of nature management should not lead to irreversible violations of the natural environment; it is very seldom achieved in practice. Mining, transportation, storage and usage of oil products are the most agressive sectors by the amount of technogenic factors that negatively influence the natural environment. At the modern stage of development of technologies, applied in the oil industry, and because of various accidents, more than 3 million tons of oil waste is generated only in Russia annually, the predominant amount of the waste is accumulated in sludge pits [1]. About 100 million tons of the oil waste has been accumulated in total. The waste of the oil industry is a source of environmental pollution and represents danger, because an effective technology of waste disposal is missing [2]. Analysis of technological solutions for the oil products waste processing with the production of materials applied in construction and other sectors during processing will not only reduce ecological damage from accumulation and storage of waste, but also provide quality products.
Determination of the effective thickness of an open cell foam filter using numerical simulation
Authors: Soloveva O V , Solovev S A , Yafizov R R , Khusainov R R
Published: July 2019

Numerical simulation of the aerosol flow in a tube with a porous insert (which is a filter model) of the fixed porosity of ε = 0.6 and with different cell diameters was performed. The method of constructing the geometry of the open cell foam material is described. Images of the trajectories of inertia and low-inertia particles inside the porous medium are presented. Figures of changes in the efficiency of particle deposition are presented for a typical filter pore diameter of d
c = 4 mm, d
c = 5 mm and d
c = 6 mm for different thicknesses of the porous insert. It is revealed that the effective thickness of the porous insert, with which the value of the deposition efficiency of media with different pore diameters does not change, is 4 cm. Recommendations are given on the choice of filtering open cell foam materials with specified parameters.
Application of fuzzy logic methods to modeling of the process of controlling complex technical systems
Authors: Beckel L S , Semenenko M G , Tsarev R Y , Yamskikh T N , Knyazkov A N , Pupkov A N
Published: July 2019

In recent decades, the concept of “fuzzy” control has emerged in engineering practice, including machinery building, when a complex technical object is controlled in conditions of incomplete and / or insufficiently formalized information. Such systems are often characterized by insufficient reliability and degree of initial data formalization. One of the approaches to such objects is to use fuzzy logic methods. The first step of such processes modeling should include determination of input and output variables and their membership functions and creation of a knowledge base in the form of a set of “IF-THEN” rules. The Mathcad computing system is considered as a tool for modeling processes with fuzzy logic methods using the battery charging control process as an example. This paper presents detailed analysis of advantages and describes software implementation for the Mamdani algorithm. However the proposed approach can be used for other algorithms.
Use of expert estimate extrapolation method for selecting sourdough starter technological parameters
Authors: Derkanosova N M , Ponomareva I N , Shelamova S A , Vasilenko O A
Published: July 2019

The quality of rye bread and bread made of the mixture of rye and wheat flour is largely determined by biotechnological processes occurring during the ripening of the sourdough starter. The factors that allow regulation of this process are the parameters of the nutrient mixture and the starter technology. Among the latter, there is the dosage of malt in the nutrient mixture, the ratio of fermented sourdough and the nutrient mixture, its humidity. The use of the specific decision depends on the experience and professionalism of the technologist. At the same time, given the complexity and multifactorial nature of the problem to be solved, decision making is not always unequivocal and guarantees the stability of the quality characteristics of the starters. Under these conditions, the use of extrapolation methods for unclear expert estimates has been proposed. The essence of this method consists in extrapolating the decision, made based on limited sample by the decision maker (DM) as a result of pairwise comparison, to the entire set of alternatives, identifying the DM’s preferences and constructing a selection mechanism based on the information received. Testing the methods based on the results of the undertaken research allows us to conclude that the proposed methods are effective in solving the problem of choosing the optimal technological parameters for preparing liquid rye sourdough starter.
Studies on operation and types of drilling pump valves
Authors: Abdyukova R Ya
Published: July 2019

The current issue of the machine building industry is improvement of oil and gas production equipment performance. However, despite the improved design and technological parameters, its reliability is still low. The time between failures depends on both severe operating conditions and quality characteristics of parts. With an increase in drilling depths, complexity of operating conditions and abrasiveness of the drilling mud, the life time of the hydraulic part of the pump decreases. Operation of drilling pumps largely depends on the design features of the valves. According to the results of theoretical studies, wear of the valve pair occurs on the bearing surface. The design of valves with different seating surfaces and shapes of the sealing element was studied. Based on the research on the improvement of the drilling pump valves, the conclusions were drawn and the tasks for further research were formulated.
Justification of constructive technological scheme of multifunctional unit
Authors: Andreev V L , Vasilyev S A , Demshin S L , Ilichev V V , Cheremisinov D A
Published: July 2019

It is developed a multifunctional soil processing unit with interchangeable working implements in the form of flat hoes to perform the subsoil tillage at 16…25 cm or cultivator hoes for carrying out pre-sowing tillage at 5…12 cm. Experimental studies of the unit have been carried out to study the effect on its traction resistance of the parameters of flat hoes, their location according to the scheme of “direct” and “reverse” wedge on the frame of unit, the optimal position of the middle plane-cutting paw relative to the side paws. The tillage unit was aggregated with the MTZ-82 tractor. The apex angle of flat hoes has been 95° and 110°, the width of their capture was 0.76 m. Processing of winter rye stubble was carried out with the use of tillage unit on heavy loamy sod-podzolic soil at its moisture content of 23.8% and hardness in the soil layer from 1.73 to 2.36 MPa. Processing of firm cultivated soil was carried out with the use of tillage unit on medium loamy sod-podzolic soil at its moisture content of 15.2% and hardness in the soil layer from 0.54 to 2.23 MPa. The traction resistance of flat hoes with a apex angle of 110°. Installation of flat hoes in the form of a “straight” wedge and the position of the middle flat hoes with the maximum displacement relative to the side flat hoes can reduce the pulling force of the tillage unit.
Electromagnetic field and eddy currents in the mantle of the ore-smelting furnace
Authors: Blanc A V
Published: July 2019

Ore-smelting furnaces are the biggest and the most powerful furnaces in which the electric arc is used for converting electric energy into heat. Studying electromagnetic field in their structural components is one of instruments in energy saving developments. Since an ore-smelting furnace is a complex electrical device, we are forced to make assumptions, which would allow reducing the complex problem to a set of more simple analytical or numerical problems admitting not only quantitative but also qualitative solutions with acceptable accuracy. There is an approach when an electromagnetic problem is reduced to calculating an equivalent circuit that comprises both resistances and reactances. For calculating electromagnetic fields, cascade equivalent circuits are well-known in electro-mechanics. Particularly, cascade equivalent circuits of magneto-electric induction heating systems may be used as prototypes for qualitative calculating electromagnetic field and eddy currents in the mantle of the ore-smelting furnace. In the paper, qualitative calculating the resistance losses in the mantle of the ore-smelting furnace with such cascade equivalent circuit is offered.
The design of the small-sized apparatus of cooling circulating water
Authors: Bondar K E , Suleymanov D F , Laponov S V
Published: July 2019

The article reviews the information on cooling the circulating water in tower coolers. It is shown that is the use of local re-cooling systems is the most relevant (small-sized devices) as they do not demand any expensive operation of extended pipeline networks, minimize emissions in the atmosphere. The designs of small-sized coolers and contact devices are also presented in this article. Currently, the used counterflow coolers have some drawbacks. The article proposes a cooling tower with a mixed current. A part of the air goes along the screw, and a part goes up helping to increase heat and mass transfer. Experiments were conducted and a comparative graph of the ratio of relative change in temperature of return water of the air flow rate was made to design the minicooler with a screw air flow in comparison with counterflow coolers. For the studied small-sized coolers in the range of ascending air flow rates up to 0.7 m/s, the relative temperature drop of the water is kept approximately in the same ratio. In the range of air flow velocities from 0.8 to 2.4 m/s, the increase in the value of the relative temperature drop of the water is more intense in the minicooler with a screw airflow. For example, at an air velocity of 1.4 m/s, the temperature difference for a minicooler with a screw air flow is 0.27. At the same time, in the specified value of the air flow velocity, the relative temperature of the water in the countercurrent minicooler is 0.24.
Features plasma gasification of organic waste
Authors: Anshakov A S , Aliferov A.I. , Domarov P V
Published: July 2019

The paper describes the main results of mathematical and experimental studies in the process of gasification of organic waste in a plasma electric furnace. In the course of research, work was carried out to study the reduction of energy consumption during waste gasification. Studies were also carried out on the effect of reducing energy consumption during waste gasification, excluding the inorganic component of waste. The article presents the results of computational and experimental studies of the gasification of organic waste and the effect of the inorganic part on the energy balance of an electric plasma furnace.
Preliminary study of tubular peat extrusion
Authors: Mikhailov A V , Fedorov A S , Garmaev O Z
Published: July 2019

This work describes the preparation and characterization of tubular peat granules for potential use in the field drying process, consisting of a mixed peat structure. Hollow peat tubes having internal diameter 30 mm and overall diameter 60 mm were produced by extrusion and used as a unit for the field drying process. The primary goal of this report is the development of the combination of fiber peat (top layer of deposit) with plastic peat (bottom layer of deposit) without additives and binders for producing a more stable and cohesive granule. The content of the mix was 1:5 by volume. When the moisture content was increased to 80% by mass (weight), moist pellets were formed. A simple test was performed on the peat samples to confirm the mixing efficiency. The advantage of such tubular geometry is that it provides 1.6 times higher surface area/volume for field drying process intensification. Promising results were achieved, in particular, when tubes with a bigger diameter were used. The method is inexpensive and simple to scale; however, further research is needed in view of a final optimization.
About possibility of immediate evaluation of technical condition of mining equipment using signal value of acoustic emission friction
Authors: Knyazkina V I , Safronchuk K A , Ivanov S L
Published: July 2019

An experiment was conducted to confirm the reliability of the evaluation of the technical condition of transmission elements during operation in terms of the magnitude and nature of the acoustic emission signal, while completing the negative effect of the artificial environment on the durability of the transmission elements. Thus, the results of the experiment are presented where the acoustic emission signal in the friction pair was changed depending on the pressure value in the contacting pair and the angular velocity value. The possibility of obtaining an estimate of the technical state of the transmission elements during its operation in terms of acoustic and emission characteristics has been experimentally confirmed.
Design changes of injection and supply wellhead fittings operating in winter conditions
Authors: Kuleshova L S , Kadyrov R R , Mukhametshin V V , Safiullina A R
Published: July 2019

The article deals with design changes in the existing injection well fittings. Disadvantages of the existing fittings are stagnant zones, considerable height and dimensions which cause problems of thermal insulation leading to rapid freezing of wellhead equipment in winter. At low temperatures, supply lines freeze and fail. The design of small-sized fittings of injection wells was developed. Elastic rubber cords, which absorb pressure caused by ice expansion due to water freezing and prevent rupture of the supply lines, are recommended to use.
On the issue of mathematical modeling of rotary kiln operation in order to reduce fuel consumption
Authors: Osintsev K V , Prikhodko I S
Published: July 2019

In accordance with the operation principle of the rotary kiln of limestone and its shortcomings, the authors developed the foundations of a mathematical model. The ultimate goal of building algorithms for the proposed method is to reduce fuel consumption when using a rotary kiln. The paper proposes to use a mathematical model based on the method of energy balances. The scientific novelty is that for a rotary kiln for the first time it is proposed to use the method of energy balances by heating zones, depending on the type of fuel burned. The procedure of inputting initial data for mathematical modeling of heat transfer processes allows us to identify the largest heat fluxes in various zones of the furnace. After that, an optimization procedure is carried out using, among other things, objective functions, as well as nonlinear programming. In the end, such calculation algorithms allow us to make recommendations to reduce heat losses in a rotary kiln and a refrigerator, as well as to reduce specific fuel consumption.
Development of heat exchanger for heat recovery of process gases
Authors: Sysoev I A , Sysoeva T I , Kondrat’ev V V , Kolmogortsev I V , Kolosov A D , Ershov V A
Published: July 2019

Due to new requirements of the Russian laws on the environment and energy efficiency, studies on effective methods for recovering waste heat from flue gases are crucial. Most oil and gas, metallurgy and chemical manufacturers remove high-temperature process gases. Gas cooling preceding cleaning reduces a volume of cleaned gases. For example, the most efficient dust and gas cleaning systems usually operate at a gas temperature of up to 200 °C. An increase in gas temperature can cause irreversible deformations of metal structures of the gas cleaning equipment and its premature failure. In addition, bag filters used for gas cleaning have strict limitations on gas temperature. As a part of the present project, an optimal design of staggered heat exchange elements in the form of perforated copper ribs was developed. The design documentation was developed and an experimental heat exchanger was designed. To monitor and control heat exchanger parameters, sensors were installed on the experimental heat exchanger (EHE). The algorithms of the automated system were developed. Laboratory and pilot tests proved the efficiency of the equipment designed for cooling waste process gases. The heat exchanger can be installed in gas flues of various diameters. The number of cooling units depends on technical requirements and operating and installation conditions.
To the question of the estimation of the impact of transport streams on the ecosystems of roads
Authors: Sushkov S , Burmistrova O , Timokhova O , Timokhov R , Burmistrov V , Chemshikova Y , Mikhaylenko E
Published: July 2019

The article is devoted to solving the actual problem of assessing the environmental situation and the choice of options for further development of economic and economic activity of man without destroying the stability of the natural environment. This article discusses a system designed to support the analytical activities of forest enterprises. An assessment of the environmental situation in the area of operations of enterprises is presented. The choice of options for further development of human economic and economic activities is aimed at sustainable development without destroying the stability of the natural environment.
Improving the efficiency of technological machines in the interaction with adhesive materials at negative temperatures
Authors: Zenkov S A , Balahonov N A , Kirichenko O P
Published: July 2019

In this paper, the object of study is a technological machine that develops the cohesive ground. The MAXFLIGHT 04 anti-icing fluid is considered as a means of controlling the adhesion of the “soil-to-metal” system used in the operation of technological machines while developing moist cohesive soils under negative temperatures. The aim of the study is to increase the productivity and efficiency of technological machines in the developing wet cohesive soils at negative temperatures by reducing the soil-to-metal adhesion. Mathematical processing of the research results allowed us to obtain regression equations for two working conditions: a regression equation without using prophylactic agents to reduce soil adhesion and a regression equation using the MAXFLIGHT 04 anti-icing fluid. Using the obtained regression equations, the proportionality coefficient (the reduced friction coefficient f) was calculated. According to the calculation results, the values of the obtained proportionality coefficient depend on the shear plane of the temperature.
Virtual prototype for co-simulation of hub-motor dynamics with brushless DC motor and elements of fault-tolerant control
Authors: Bushuev D A , Kiseleva T Y , Rubanov V G
Published: July 2019

The paper describes the virtual prototype of the hub-motor with a planetary gear, brushless direct current motor (BLDCM) and a fault-tolerant control system for Hall Effect sensors failure. The co-simulation model of the BLDCM control system with integration of the hub-motor mechanical part constructed in MSC Adams software based on PI controllers, pulse width modulation (PWM), and fault-tolerant algorithms for Hall Effect sensors failure is described. Simulation results of the hub-motor virtual prototype with the fault-tolerant control system are shown and discussed.
Analysis of the working processes of electromagnetic pulse machines
Authors: Neyman V Yu , Markov A V
Published: July 2019

The tendency of constructing variants of electromagnetic pulse machines of shock action is considered. A brief description of different variants of electromagnetic machine design is given and their comparison is made. Based on the energy balance in the electromechanical system, the working processes in these machines are analyzed. The engineering-and-economical performance of the electromagnetic machines is increased by preliminary accumulation of potential and magnetic energy in the working cycle of the machine.
Operating modes of vacuum plasmatrons with hollow cathodes
Authors: An’shakov A S , Cherednichenko A V , Serikov V A , Domarov P V
Published: July 2019

Results of experimental studies of starting characteristics of vacuum plasma torches in glow discharge mode with switching to abnormal glow discharge and arc discharge are presented. It is demonstrated that if high-frequency current source is used parallel to direct current, ion current is increased and the time of starting mode is reduced. Experimental smelts of tantalum, tungsten, molybdenum, zirconium, and titan were carried out in operating modes with measurement of liquid metal surface temperature in relation to the supplied heating power.
Features of the operating modes of a hot hollow cathode in a vacuum arc discharge
Authors: Cherednichenko A V , Zuev S P , Serikov V A
Published: July 2019

The design features of the hot hollow cathode, its thermionic characteristics and current-voltage characteristics of a vacuum arc discharge with plasma-forming gases of helium and argon are considered. The rationale for these characteristics based on the theory of vacuum-arc discharge is given. The article discusses the use of a hollow cathode discharge for processing tantalum powders.
Study of forming conditions of technogenic materials in the unit with elastic forming elements
Authors: Sevostyanov M V , Martakov I G
Published: July 2019

The article presents scientific and technical developments and analytical studies of the process of forming technogenic materials in a press-roller extruder equipped with pressing bodies — rollers with elastic forming elements. Technical solutions implemented in the design of the unit provide reliable capture of the charge by the forming rolls, uniform distribution of stresses along the material compression arc, as well as increasing the operational reliability of the machine. This is important when forming technogenic materials with different physical-mechanical and rheological characteristics.
Electromagnetic interference filter for spacecraft power bus
Authors: Zhechev Y S , Kosteletskii V P , Zabolotsky A M , Gazizov T R
Published: July 2019

The paper considers the protection of radio-electronic equipment against common and differential mode interference by means of a filter based on lumped elements. The authors have developed a schematic diagram of the filter to be used in power supply circuits of a spacecraft, and present and compare the results of circuit simulation and experiment. The results are useful for further development of noise protection devices for the spacecraft power bus.
Calculation of power and energy indicators of the process of materials rapture during their processing with the help of an inertial tool with a curved cutting rim
Authors: Bondarenko I R , Volkov D Yu , Kovalev LA
Published: July 2019

The article presents the research which reveals the analytical dependences for the determination of the strength and energy characteristics of the process of materials rupture during their processing with an inertial tool with a curved cutting surface. The research was performed on the basis of the laws of classical mechanics, as well as existing models of the destruction of brittle materials. The revealed dependencies reflect the interrelation of power and energy indicators of the instrument and its structural and technological parameters of work, as well as the mechanical characteristics of processed material. According to the results of a brief comparative analysis of the values of power of processing, obtained from the analytical dependence and the results of a trial experiment, the assessment of the applicability and further improvement of the obtained analytical dependencies was made.
Development of modal filter prototype for spacecraft busbar protection against ultrashort pulses
Authors: Khazhibekov R R , Zabolotsky A M , Zhechev Y S , Kosteletskii V P , Gazizov T R
Published: July 2019

The protection of the onboard equipment of the spacecraft from an ultrashort pulse (USP) based on modal filtering is proposed. The paper presents the results of the development of a modal filter (MF) prototype with a broad-side coupling. When choosing a structure, the maximum bus current, insulation breakdown voltage, wave impedance of line and the duration of the interfering USP are taken into account. To substantiate the choice of structure, quasi-static and electrodynamic simulations are performed. The simulation showed that the MF with resistance of 50 Ω at both ends of the passive conductor effectively weakens the 0.45-ns USP by 4 and with non-resistance connection on the passive conductor by 7. The MF prototype without resistors is made. Frequency dependence of |S
21| is measured. An experiment showed that the MF weakens the USP by 5.61. The bandwidth of the MF is 60 MHz.
The choice of rational stiffness joints parameters of the cabin suspension levers in the vehicle
Authors: Polyakov Yu A
Published: July 2019

The article is devoted to the choice of rational stiffness parameters of the joints in the suspension levers in the vehicle cabin. The method of formation of cabins dynamic models at their inclusion in spatial dynamic models of vehicles is offered and programmatically realized. In the known methods, the attachment of the cabin to the frame is not taken into account or simulated using linear springs with parallel inclusion of linear dampers or without them. The proposed method deals with the geometric features of the lever guide apparatus, the location of shock absorbers and elastic elements, the presence of a stabilizer in the cabin suspension. In addition, the elastic-damping properties of the mounting parts of the cabin suspension elements are considered. This made it possible, even at the design stage, to investigate the effect of the stabilizer’s torsional stiffness and the stiffness of the cabin suspension joints on the vibration loading of the cabin and the driver’s seat, which are noticeable at frequencies above 7 Hz.
Oscillations of circular cylindrical shells with imperfections of shape
Authors: Seregin S V
Published: July 2019

The impact of initial irregularities of ideal circular cylindrical shape on bending vibrations of thin shells is studied. For the first time ever, the possibility of appearance of the additional splitting zone of the flexural frequency spectrum caused by the shell having initial shape irregularities has been described. It is established that the splitting of the frequency spectrum happens not only when the number of waves of circular dynamic deformations is equal to the number of waves of shell shape irregularities (as it was previously thought), but also when the number of shape-generating waves is twice as low as the number of shape irregularity waves.
Durability and corrosion resistance of high-strength powder concretes
Authors: Tolstoy A D , Lesovik V S , Glagolev E S , Yakimovich I V , Krzhivitsky A A , Khakhalev V P , Krymova A I , Artebyakin V M
Published: July 2019

One of the performance indicators of building products and structures made of high-strength concretes is their durability, which determines the urgency problem of preserving high construction and technical properties over time. In this regard, an important task is to create new ways of the durability prediction and corrosion resistance of high-strength concretes in conditions of aggressive environmental exposure. This article discusses the issues of determining the durability of high-strength powder concretes under the action of one of the most common aggressive factors is sulfate solution. The results development of an accelerated method for predicting the durability of powder concretes in sulfate medium are presented.
Self-restoration hardening systems of high-strength concrete of a new generation
Authors: Tolstoy A D , Lesovik V S , Glagolev E S , Vodopyanov I O
Published: July 2019

Preservation over time of the characteristics of high-strength artificial rock materials is currently the most important task. The operating practice critical structures, such as, for example, tall frame buildings, shows, unfortunately, the insufficient durability of the in-situ reinforced concrete from which these structures are constructed. Internal corrosion processes are complemented by external aggressive effects (temperature and humidity changes, changes in the gas composition of the ambient air, etc.). This article deals with issues of self-restoration (“autogenous healing”) of the concrete structure. Their solution is provided by a method of overgrowing the interaction products of elements of an aggressive solution (external factor) and components of hardening concrete (internal factor).
Consideration of welding stresses when welding technological rectangular cutouts
Authors: Velikanov N L , Koryagin S I , Sharkov O V
Published: July 2019

The article discusses the method for determining the prestress fields in hull structures with a rectangular cutout. After welding of the cutout the fields of residual welding stresses in the welding area are summed up with the prestresses. Methods of the mathematical theory of elasticity (the complex potentials in particular) are used. It is assumed that a uniform stress state is created in the plate in the absence of welds. Welding causes a disturbance in the uniform stress field. It is proposed to use complex potentials for writing the weld boundary conditions corresponding to the absence of displacements at their boundary. An example of a method of creating prestresses in the plate when welding a rectangular hole is given.
Limitation of the dynamic load in the hoist mechanism of the shovel based on the additional drive
Authors: Kuznetsov N K , Iov I A , Iov A A
Published: July 2019

In the article, the results of studies of the synthesis of the optimal structure and parameters of the electromechanical system of the hoist mechanism of the rope shovel EKG-8I, which provides the limitation of dynamic loads, are presented. The procedure of structural-parametric synthesis is described, which is based on the determination of the required control actions, independent from the structure of the control system of the hoist mechanism. Control actions were found by solving the inverse dynamic problems for a given type of oscillatory motions of the dipper in the start-up and load change modes. Based on the expression of the obtained time dependencies through the phase coordinates of the system and its combinations, the structure and parameters of the control system were found. The found structure of the control system of the standard electric drive of the hoist mechanism and the additional drive ensures the implementation of a given law of motion of the dipper. The numerical simulation of the electromechanical system of the hoist mechanism with an additional drive confirmed the effectiveness of using the proposed approach of reducing the dynamic loads with maintaining the productivity of the excavator.
The results of bearings diagnostics of ship electric motors and generators
Authors: Sergeev K O
Published: July 2019

The article discusses the results of in-place diagnostics of rolling bearings of ship generators and electric motors, carried out on more than one thousand five hundred units. The main methods for diagnosing the technical condition of rolling bearings, applied in the diagnostics on ships, are considered. The statistics of detection of various types of rolling bearing defects is given. The conclusions on the reliability of bearing assemblies with rolling bearings are drawn. The directions for further improvement of diagnostic methods and work practices are indicated.
Comparative evaluation of austenite grain in high-strength rail steel during welding, thermal processing and plasma surface hardening
Authors: Kolosov A D , Gozbenko V E , Shtayger M G , Kargapoltsev S K , Balanovskiy A E , Karlina A I , Sivtsov A V , Nebogin S A
Published: July 2019

In the process of plasma surface hardening, a surface layer that consists of zones of different sizes with different phase and structural composition is formed. The minimum grain size for plasma surface heating is determined by the initial austenitic grain. Its size depends on the dispersion of the initial structure. The rate of plasma heating at 200-1000 °C/s affects the size of the initial grain. The further growth of austenite crystallites with an increase of temperature essentially depends on the heating rate: small rates and high temperatures of plasma surface heating can lead to a significant enlargement of the grain. Increase of the heating temperature in the zone of thermal influence during welding from 900 to 1040 °C of rail steel 76F leads to the growth of the austenitic grain from No. 9 to No. 7 and individual grains – from No. 8 to No. 3. The largest austenite grains while heated at 1000 and 1040 °C form separate zones where conglomerates of large grains predominate. Stiffness of 76F steel, heat-strengthened on the troosto-sorbitol structure, deteriorates substantially when the temperature of rapid heating increases from 900 to 1040 °C. This also increases the instability of stiffness.
Investigation of macro and micro structures of compounds of high-strength rails implemented by contact butt welding using burning-off
Authors: Shtayger M G , Balanovskiy A E , Kargapoltsev S K , Gozbenko V E , Karlina A I , Karlina Yu I , Govorkov A S , Kuznetsov B O
Published: July 2019

Investigations of the structural components of rail joints, obtained by contact butt welding using burning-off, which are revealed on the surface of kinks after the destruction of the compounds during static bending tests and after destruction in operating conditions, were carried out. Analysis of the microstructure and chemical heterogeneity of the fracture surface was carried out with the help of a scanning electron microscope JEOL JIB-Z4500, equipped with an attachment for energy-dispersive analysis. The analysis showed that the main structural defects were poor penetration and inclusions of iron-manganese silicates that significantly reduced the parameters for mechanical tests of welded joints. Their presence in welded joints is unacceptable. Clusters of inclusions of aluminosilicates, so-called matte spots, and oxide films of a more complex composition are formed in the compound on the basis of non-uniformly distributed nonmetallic inclusions of the metal of the rail.
Pulse-contact frictional interaction of microprotrusions of friction pairs of brake devices
Authors: Volchenko N A , Volchenko D A , Polyakov P A , Krasin P S , Fedotov E S , Evchenko A S
Published: July 2019

The article materials disclose contact-impulse frictional interaction of microprotrusions of friction pairs of strip-block brakes, based on the principles of the gradient theory of electric and thermal fields. The effect of “transistor” was applied by selecting friction pairs of the brake to reduce their energy loading, and as a result, wear resistance increase.
Choosing the materials performance and the form of an indenter for arrangement of texture at the surface of skin mill rolls
Authors: Ogarkov N N , Platov S I , Zvyagina E Yu , Molochkova O S , Makarova I V
Published: July 2019

The fraction for forming texture of rolls surface of the training mills is investigated in this work. The fraction from various manufacturers has been estimated by comparing the most important characteristics. Metallographic studies of the steel fraction microstructure were carried out on the MEIJI 2700 optical microscope (Japan). Automated processing of measuring results of various shapes indenters microhardness was conducted. Comparing the obtained results with the characteristics declared by the manufacturers was carried out. The rolling roll surface microstructure with which the texture of the cold-rolled strip surface is formed, is investigated in the paper. Roller steel widely used at present as well as the most common methods of rolling roll surface microrelief forming, such as mechanical and electroerosion ones, are discussed in the work. It was established that with the electroerosion method, a more uniform structure with a smoothly changing microrelief was formed on the surface of the roll as compared with the mechanical action of the abrasive. According to the results of the research, recommendations were formulated on the use of the fraction that has the best performance characteristics and which allows one to obtain surface roughness by transferring it to the surface of a cold-rolled strip in accordance with the requirements of consumers.
Modern approaches to water drying in the underground transport system
Authors: Porsev E G , Gavrilova Zh L
Published: July 2019

The analysis of the process of electroosmotic water depletion in soils surrounding the track structure of the underground is given. It is established that due to the fact that the structure of soils is disturbed during the construction of the underground, the electroosmotic water loss in them has its own peculiarities, therefore it is necessary to optimize the process by the criterion of specific energy inputs for mass transfer.
Improving efficiency of flexible manufacturing system based on optimal readiness of technologies
Authors: Pishchukhin A M , Akhmedyanova G F
Published: July 2019

The efficiency of using flexible manufacturing systems (FMS) depends on their workload. However, in order for the FMS not to work for the warehouse, it is necessary to coordinate its production with the requirements of the market. Both the market and the production process are stochastic, so the probabilistic matching of these two processes based on the Kolmogorov equation is considered in the paper. The level of approval is estimated by the difference in the probability density of the market price for a product exceeding the level of its production cost using the technology implemented in FMS. The latter probability density assesses the readiness of technologies for implementation, including the availability of raw materials, materials, energy, serviceable equipment and devices – all of this is spent on managing resources. The optimal allocation of these control resources in the preparation of technologies can significantly improve the efficiency of FMS. Of practical significance is the identified logarithmic relationship between the probability density of the demand for this product on the market and the probability density of the readiness of the technology implemented in this FMS for the production of this product in the required amount and allocated financial means to improve this readiness.
Catalytic pyrolysis of biomass of solid compounds used for gasoline production
Authors: Igtisamova G R , Yangirova Z Z , Nosirov D Sh
Published: July 2019

The article examines the latest achievements of foreign researchers whose key focus is to obtain gasoline fractions from the biomass of solid compounds using catalytic pyrolysis for its further use in industrial sectors. The biomass of solid compounds is studied as a raw material for production of gasoline fractions due to its low cost and high availability. In addition, several ways for obtaining and converting biomass are studied. At high temperatures (up to 800° C) solid is used to produce synthesis gas by partial oxidation in an autothermal packed bed reactor over catalysts. Biomass is an acidic flammable liquid containing more than 300 compounds. Industrial biomass is not compatible with existing liquid transportation fuels, including gasoline and diesel. In order to use biomass as a conventional liquid transport fuel, it must be catalytically modernized.
Economic assessment of the need for processing of raw materials of animal origin
Authors: Popov V P , Dudorov V E , Sidorenko G A , Akhmadiyeva Z R , Tsyrkaeva E A , Sagitov R F
Published: July 2019

The search for new effective methods of processing of secondary raw materials in the food industry is a very urgent problem. The biological waste of the food and processing industry is considered to include veterinary confiscates, nonfood waste and little value food products, waste products of food, technical and special products, the corpses of livestock and poultry. This waste has been and remains a valuable secondary raw material. The reasons are our Russian mentality, which allows us to neglect the environment, certain economic reasons and the inefficiency of the supervisory bodies. In Soviet times, large processing plants had workshops for production of feed, fish, feather, horn and hoof and other flour. Waste of smaller enterprises was brought to special plants, where they were either burned or used for production of the same flour. Most of these plants had not been working for a long time, and the rest ones did not cope with the supplied volume of waste. The other side of the problem is that both these plants and the vast majority of enterprises that have their own production of feed and other animal flour use obsolete old technologies and old equipment. The result is a product with low consumer qualities. The variety of nonfood waste of the food industry and the diversity of their application imply the use of different technologies of utilization. And the more advanced these technologies, the higher the profitability of processing and the quality of the products.
Congruence Between 1994 WHO Classification of Endometrial Hyperplasia and Endometrial Intraepithelial Neoplasia System
Authors: Travaglino Antonio , Raffone Antonio , Saccone Gabriele , Mascolo Massimo , Guida Maurizio , Mollo Antonio , Insabato Luigi , Zullo Fulvio
Published: July 2019

Objectives

To assess congruence between World Health Organization (WHO) 1994 and endometrial intraepithelial neoplasia (EIN) classification systems of endometrial hyperplasia.

Methods

Systematic review and meta-analysis were performed by searching electronic databases for studies that classified endometrial hyperplasia according to both WHO 1994 and EIN systems. Congruence was based on the rate of specimens classified as EIN in WHO categories, which should be virtually 0.000 in nonatypical hyperplasia (NAH) and 1.000 in atypical hyperplasia (AH). Subgroup analyses were performed based on architecture complexity.

Results

Eight studies with 1,352 hyperplasias were included. Congruence with EIN criteria was fair in NAH (0.241) and moderate in AH (0.815). Subgroup analyses of NAH showed high congruence in simple NAH (0.065), null in complex NAH (0.517), null in simple AH (0.148), and high in complex AH (0.901).

Conclusions

WHO 1994 system is not congruent with the EIN system and cannot be directly translated into a dual classification.
Quantile regression for challenging cases of eQTL mapping
Authors: Sun Bo , Chen Liang
Published: July 2019

Mapping of expression quantitative trait loci (eQTLs) facilitates interpretation of the regulatory path from genetic variants to their associated disease or traits. High-throughput sequencing of RNA (RNA-seq) has expedited the exploration of these regulatory variants. However, eQTL mapping is usually confronted with the analysis challenges caused by overdispersion and excessive dropouts in RNA-seq. The heavy-tailed distribution of gene expression violates the assumption of Gaussian distributed errors in linear regression for eQTL detection, which results in increased Type I or Type II errors. Applying rank-based inverse normal transformation (INT) can make the expression values more normally distributed. However, INT causes information loss and leads to uninterpretable effect size estimation. After comprehensive examination of the impact from overdispersion and excessive dropouts, we propose to apply a robust model, quantile regression, to map eQTLs for genes with high degree of overdispersion or large number of dropouts. Simulation studies show that quantile regression has the desired robustness to outliers and dropouts, and it significantly improves eQTL mapping. From a real data analysis, the most significant eQTL discoveries differ between quantile regression and the conventional linear model. Such discrepancy becomes more prominent when the dropout effect or the overdispersion effect is large. All the results suggest that quantile regression provides more reliable and accurate eQTL mapping than conventional linear models. It deserves more attention for the large-scale eQTL mapping.
Cooler: scalable storage for Hi-C data and other genomically labeled arrays
Authors: Abdennur Nezar , Mirny Leonid A
Published: July 2019

Motivation

Most existing coverage-based (epi)genomic datasets are one-dimensional, but newer technologies probing interactions (physical, genetic, etc.) produce quantitative maps with two-dimensional genomic coordinate systems. Storage and computational costs mount sharply with data resolution when such maps are stored in dense form. Hence, there is a pressing need to develop data storage strategies that handle the full range of useful resolutions in multidimensional genomic datasets by taking advantage of their sparse nature, while supporting efficient compression and providing fast random access to facilitate development of scalable algorithms for data analysis.

Results

We developed a file format called cooler, based on a sparse data model, that can support genomically labeled matrices at any resolution. It has the flexibility to accommodate various descriptions of the data axes (genomic coordinates, tracks and bin annotations), resolutions, data density patterns and metadata. Cooler is based on HDF5 and is supported by a Python library and command line suite to create, read, inspect and manipulate cooler data collections. The format has been adopted as a standard by the NIH 4D Nucleome Consortium.

Availability and implementation

Cooler is cross-platform, BSD-licensed and can be installed from the Python package index or the bioconda repository. The source code is maintained on Github at https://github.com/mirnylab/cooler.

Supplementary information

Supplementary data are available at Bioinformatics online.
MEpurity: estimating tumor purity using DNA methylation data
Authors: Liu Bowen , Yang Xiaofei , Wang Tingjie , Lin Jiadong , Kang Yongyong , Jia Peng , Ye Kai
Published: July 2019

Motivation

Tumor purity is a fundamental property of each cancer sample and affects downstream investigations. Current tumor purity estimation methods either require matched normal sample or report moderately high tumor purity even on normal samples. It is critical to develop a novel computational approach to estimate tumor purity with sufficient precision based on tumor-only sample.

Results

In this study, we developed MEpurity, a beta mixture model-based algorithm, to estimate the tumor purity based on tumor-only Illumina Infinium 450k methylation microarray data. We applied MEpurity to both The Cancer Genome Atlas (TCGA) cancer data and cancer cell line data, demonstrating that MEpurity reports low tumor purity on normal samples and comparable results on tumor samples with other state-of-art methods.

Availability and implementation

MEpurity is a C++ program which is available at https://github.com/xjtu-omics/MEpurity.

Supplementary information

Supplementary data are available at Bioinformatics online.