The paper describes the main agents, with their components and process diagrams, of the developed simulation model of the functioning of the distributed information processing system, created in the AnyLogic software environment. A method for constructing models with self-similar traffic is described. The article also presents a method for obtaining real (reference) indicators of the average response time of the system to user requests. The results of numerical experiments on the created models of the functioning of distributed information processing systems with self-similar traffic are presented. The main conclusions about the performed experiments are presented.
Keywords: distributed information processing system, self-similar flow, average system response time, simulation, object-oriented concept, agent-based and discrete-event modeling
The analysis of the use of renewable energy sources in Russia is carried out. The main features of the use of energy-efficient technologies in construction are considered. On the example of the construction of a 9-storey residential building, a comprehensive analysis of the construction area is performed. Solutions with the use of energy-efficient and green technologies are proposed.
Keywords: construction, energy-efficient technologies, green technologies, renewable energy sources, energy saving, energy efficiency
The article considers the issue of measuring and controlling the parameters of a high-voltage AC circuit using a Bragg grid. A model of a fiber-optic sensor based on the magnetostriction effect, the main component of which is a fiber-Bragg grating, is proposed. The 3D modeling of the magnetostriction process and the design of the block diagram are carried out.
Keywords: optical fiber, magnetostriction, bragg grid, AC, sensor, solenoid, coil, nickel, ferrite, MathCAD, COMSOL
Mathematical modeling and optimization of the process of controlling the sulfate regime when the apatite load changes on the phosphoric acid extractor is considered. It is shown that the preservation of the "sulfuric acid/apatite" ratio with a sharp change in the apatite consumption leads to a violation of the technological regulations for SO3. The algorithm of correction of this ratio in the transition mode is developed, which minimizes the probability of violation of the regulatory indicators. A variant of implementing the optimal apatite load correction procedure using stand-alone scenarios is proposed. The results were confirmed during the simulation.
Keywords: algorithm, mathematical model, stabilization of the sulfate regime, extraction phosphoric acid, change in the load on the extractor, phosphorus yield coefficient from apatite, optimization, autonomous scripts
This article provides information on the possibility of using offshore wind farms to provide energy to offshore structures such as oil and gas platforms, as well as coastal communities.
Keywords: wind power plant, wind generator, offshore power plant, SIEMENS generator, offshore oil and gas facility, oil and gas field, coastal settlement
To determine the optimal set of machines for the production of earthworks in urban conditions, it is necessary to make a multi-criteria selection of the set among possible combinations of machines, with each parameter having a certain level of influence. To determine the weight of the parameters, it was decided to conduct an expert survey. The minimum number of experts was determined, a survey was conducted, after which the data was processed, the level of consistency of the expert opinion was obtained, and the level of influence of each parameter on the choice of sets of machines was revealed.
Keywords: parameters that affect the choice of machine sets, expert survey, Kendall concordance coefficient, earthworks, Pearson coefficient
The article is devoted to the comparative analysis of the architectural features of the medieval temples of Simon the Cananite in New Athos (Abkhazia) and the Northern Zelenchuksky in Karachay-Cherkessia (Russian Federation) in the context of three-courtyard temples, the study of prototypes of their architectural forms, the description of the results of the analysis of building solutions of temples based on the X-ray phase method. This method is used for the study of these temples for the first time. The scientific novelty of the article is due to the fact that a comprehensive study of the planning, spatial solution and building material of the temples of Simon Kananit and Northern Zelenchuksky, based on the results of physico-chemical analysis, allows us to confirm their dating to the X century and establish the chronological proximity of the two monuments.
Keywords: medieval architecture of Abkhazia and Alanya, three court temples, X-ray phase analysis
Blasting operations are often the only way to prepare the material for the recess for laying roads and railways in the rocks. Explosive loosening is also used to extract stone as a building material. Field testing is costly and often dangerous. Therefore, it is necessary to first conduct a series of experiments on the model and find out the conditions for ensuring good quality loosening of rocks. In order for the results of model tests to be transferred to nature, a similarity between model and specimen is required. The approximate similarity is achieved by the equality of the similarity criteria for the model and specimen. The characteristic similarity criteria are obtained by analyzing the physical quantities inherent in a mechanical system using the theory of dimension and similarity. The received criteria are presented in the classical form. These are the criteria of Strouhal, Froude, Cauchy and Newton.
Keywords: explosive loosening, rock material, deceleration interval, similarity criterion, modeling, rock density, model, specimen, expansion height, dimensionality, physical quantity
This paper reports on the results obtained on the diagnostics of a steam pipeline of a thermal power plant; it analyzes the effect of thermal fatigue on the structure and properties of the 12Kh1MF steel and possible reasons for the emergency destruction of steam pipeline elements before the exhaustion of economic life. Ultrasonic testing and additional heat treatment are proposed to be used for the detection and elimination of structural inhomogeneity in the metal. The applicability of statistical technique to analyzing data on the loading history of a steam pipeline is studied, which enables us to evaluate the damaging effects of loading cycles and to develop a plan of preventive measures, as well as to increase the accuracy of predicting the residual life of steam pipeline elements.
Keywords: metallic structure, diagnostics, degradation, steam pipeline, thermal fatigue, microstructure, mechanical properties, residual life
The results of theoretical research and analysis of methods that will significantly reduce the weight of the gravity oil platform are presented. At the same time, its static, dynamic, and shear stability will remain under the influence of wind, wave, ice load and current load. In order to reduce the weight and overall dimensions, it is proposed to outline the lower part of the platform base with a metal sheet pile wall. As a result of theoretical studies, the dependence of the shear force under the influence of external forces acting on the platform during operation on the physical and mechanical properties of the soil and the size of the sheet pile wall is found, which will significantly reduce the weight of the platform and the cost of its construction.
Keywords: gravity oil platform, shear stability, tongue-and-groove wall, external forces acting on the platform, rollover stability
The article describes the main stages of development of the construction of green roofs in Russia and abroad, the basic scheme and the technology of green roofs.
Keywords: Green construction, green roofing, environmental certification, noise pollution, drainag
The article presents the results of experimental studies of microclimate parameters (temperature, intensity of thermal radiation) at the area of an arc steelmaking furnace, on the basis of which the adequacy of mathematical models of heat transfer implemented in the ANSYS software package is confirmed. Mathematical models of heat transfer are represented by the discrete ordinate model (DO), which most accurately describes the transfer of radiative heat in space, and the Shear Stress Transport (SST) turbulence model. The use of these mathematical models will make it possible to pre-evaluate the thermal radiation situation at the projected or reconstructed objects, and also will allow you to choose effective means of thermal protection in advance.
Keywords: arc steelmaking furnace, mathematical models, experimental studies, heat transfer, temperature, intensity of thermal irradiation
The paper studies the applicability ofthe coercive force (Нс) as a parameter for measuringthe wall thickness ofpipelines,vessels,andother metallic structuresthroughnonmagnetic insulationduring material degradation undercorrosion conditions. A procedure is developedfor remote inspectionof metallic structures atsites of maximum corrosion rateby the coercimetricmethod,withoutbreaking the insulationandstopping the operation ofthe object being tested.The effects of metal thickness, the size ofthe poles of the magnetizer, andthe thickness of non-ferromagneticinsulationon the absoluteand relativevalues of the coercive force are comparatively analyzed. The application of theproposed relative value methodis shown to be able to decrease significantlythe effectof steel composition and structureonthe metal thickness dependence of Нс. The results of measuring the coercive force of differently thick 09G2S steel specimens through non magnetic insulation are presented, as well as the behavior of the relative values of the coercive forceas dependent onmetal and insulation thickness.Foridentical metal thicknesses, the absolute values of the coercive force of different steels may differby a factor of 10 ormore, whereasthe difference in the relative values of Нс with equally decreasing metal thickness does not exceed 15%. The developedtechnique isinsensitivetothe misalignment of the outer and innermetal surfaces,and itenablesthe thickness oflow-alloysteels like 09G2Sto be measured witha relative error of 10%.
Keywords: metallic structure, diagnostics, degradation, corrosion, coercive force, thickness measurement, nonmagnetic insulation
The article considered the propagation of a long impulse signal in a hydroacoustic waveguide. A solution is given for a replica of a impulse signal in the second approximation of the dispersion theory. The propagation of a single-mode and multimode impulse in a Pekeris waveguide with a bottom in the form of an absorbing half-space is simulated. The acoustic properties of the half-space correspond to medium sand with an average grain size 0,3 mm. The result of the solution in the second approximation of the dispersion theory is compared with the result of the simulation of the impulse replica obtained as a convolution of the input signal with the impulse response of the waveguide. The disadvantages of the solution in the second approximation of the dispersion theory are shown and analyzed. It is shown that the theory of dispersion incorrectly reproduces the transients when the signal is switched on and off in cases where the signal frequency lies near the critical frequency of the first or second mode. It is shown that the theory of dispersion correctly reproduces the envelope of a multimode impulse signal.
Keywords: impulse signal, normal modes, group velocity, dispersion theory, intramode dispersion, intermode dispersion
The article contains an analysis of the design and calculation process in the 3d system NX Siemens oil and gas facilities. Research methodology - analysis of scientific literature on a given problem, as well as practical domestic experience. Creation of a 3D model of an oil and gas structure, with the possibility of changing the construction parameters at the design stage. Detailed analysis of the model, which allows you to describe in detail the stages of construction of the structure and selection for each stage of construction of specific equipment and materials. Engineering analysis modules are built into the software solution, built-in solvers are designed to calculate the different operation scenarios of the structures being developed, which make it possible to approach the real conditions of operation of the designed structure. The relevance of the use of the NX Siemens system is due to the complexity of the design of oil and gas structures and the influence of all parameters of the materials and technologies used on the performance indicators during the operation of the oil and gas structure. The same software solution allows you to prepare a complete package of design and technological documentation, prepare tasks for processing parts and materials, and ensure quality control during their manufacture.
Keywords: design, calculations, oil and gas facilities, companies, objects,