The article is based on modelling several variants of information diagrams of a corrugated monolithic ceiling of an industrial building. The information model has been transformed into an analytical model. The comparative analysis of all calculation models was carried out visually and in numerical aspect. The efficiency of BIM-technologies in design with the application of software complexes «Renga», «CAPFIRR-3D» and «LIRA-CAD» is also considered in the calculation and construction section. The comparative analysis of three variants of the joints of the beams and the slab of the covering was carried out. The analysis of the stress-distorted state of the calculation circuit was also performed.
Keywords: ribbed slab, industrial building, design of buildings and structures, BIM-technologies, calculation scheme, information model, rigid insert, stress-strain state, finite element method
The article is dedicated to the development of an automated system aimed at creating a program of works for the maintenance of road surfaces. The system is based on data from the diagnostics and assessment of the technical condition of roads, in particular data on the assessment of the International Roughness Index (IRI). The development of a program of works for the maintenance of road surfaces is carried out based on the analysis of the IRI assessment both in the short term and on the time horizon of the contractor's work under the contract. The system is developed on the principle of modular programming, where one of the modules uses polynomial regression to predict the IRI assessment for several years ahead. The analysis of the deviation of the predicted IRI value from the actual one is the basis for the selection of works included in the program. The financial module allows the system to comply with the budget framework limited by the contract and provides an opportunity to evaluate the effectiveness of planning by calculating the difference between the cost of road surface maintenance and the contract value. Practical studies demonstrate that the system is capable of effectively and efficiently planning road surface maintenance works in accordance with the established contract deadlines.
Keywords: road surface, automated system, modular programming, machine learning, recurrent neural network, road condition, international roughness index, road diagnostics, road work planning, road work program
One of the key directions in the development of intelligent transport networks (ITS) is the introduction of automated traffic management systems. In the context of these systems, special attention is paid to the effective management of traffic lights, which are an important element of automated traffic management systems. The article is devoted to the development of an automated system aimed at compiling an optimal program of traffic light signals on a certain section of the road network. The Simulation of Urban Mobility (SUMO) traffic modeling package was chosen as a modeling tool, BFGS (Broyden-Fletcher-Goldfarb-Shanno) optimization algorithm was used, gradient boosting was used as a machine learning method. The results of practical research show that the developed system is able to quickly and effectively optimize the parameters of phases and duration of traffic light cycles, which significantly improves traffic management on the corresponding section of the road network.
Keywords: intelligent transport network, traffic management, machine learning, traffic jam, traffic light, phase of the traffic light cycle, traffic flow, modeling of the road network, python, simulation of urban mobility
This article discusses the importance of timely defect detecting of automated electronic car control systems for prevention of serious failures. Also the first stage of mathematic modeling mechanism is presented, it includes construction models of the dependence of the number of failures by time with various methods of diagnosting the technical condition of the car.
Keywords: diagnosting, modeling, technical service of the car, failure, automated system, electronic control unit, engine
The article presents the derivation of the resolving equations for calculating centrally compressed concrete filled steel tubular columns of circular cross-section taking into account the effect of lateral compression and physical nonlinearity. When deriving the resolving equations, forced deformations are also taken into account, which may include creep deformations, shrinkage, and temperature deformations. Finally, the problem is reduced to a system of three equations with three unknowns for the contact pressure between the shell and the concrete core p and stresses along z in concrete and steel. As equations establishing the relationship between stresses and instantaneous deformations, the relations of the deformation theory of concrete plasticity by G.A. Geniev are used, in which dilatational deformations of concrete are taken into account. The developed technique is implemented in the Matlab environment and tested on the experimental data of A.I. Sagadatov. The agreement between experiment and theory is good enough. The constructed model is based on the most general relations of solid mechanics and is free of empirical coefficients.
Keywords: pipe concrete, column, physical nonlinearity, dilatation, deformation theory of plasticity, central compression, ultimate load, bearing capacity
The example of application of fiberglass pipes on epoxy binding at replacement of steel pipes in heat supply system is considered. Fiberglass pipes in the deals with the influence of the degree of polymerization of the binder in the composite material of pipes that does not comply with the normative values on the work of the elements of the heat supply system when the coolant passes through it. When installing pipelines made of composite materials based on thermosetting polymers operating at elevated temperatures, it is necessary to control the supplied products for compliance with its regulatory requirements with mandatory control of the degree of polymerization of binders.
Keywords: fiberglass pipes, degree of polymerization, linear thermal expansion, shrinkage stresses, quality indicators, operation
This article describes the methods of determining the technical condition of parts and assemblies of electrical equipment and also analysis of electronic engine control systems and it’s components that are most susceptible to failure as a result of automation in the automotive industry. Methods described in this article allow for diagnostics with constructional peculiarities of modern car engines taken into consideration, also most effective of them are offered.
Keywords: electronic control unit, car, engine, check, diagnostics
The algorithm of calculation of the main geometrical characteristics of the section consisting of pair angles at a bend of both angles is made. The received results are applied to definition of a carrying capacity of an element of a farm.
Keywords: a rafter farm, bend, a barycentre, a moment of inertia, a radius of inertia
The structural properties of cobalt catalysts and their active component are studied. The influence of metal oxides on the specific surface area, pore volume and size, the average crystallite size and the active surface area of the catalyst Co-Al2O3/SiO2 was studied.
Keywords: Fischer-Tropsch synthesis, synthetic hydrocarbons, catalyst, cobalt, promoter, carrier, specific surface, porous structure, catalytic activity, degree of reduction, active surface area
The physical and chemical properties of cobalt catalysts promoted by manganese oxides for the synthesis of hydrocarbons by the Fischer-Tropsch method are studied. The influence of polymorphic modifications of the alumina carrier on the specific surface area, pore volume, degree of reduction, size of cobalt crystallites,catalytic activity, dispersion degree of catalyst reduction is considered.
Keywords: Synthesis of Fischer-Tropsch, synthetic hydrocarbons, the cobalt catalyst, promoter MnO2, the carrier of Al2O3, specific surface area, the degree of recovery of the catalytic activity, dispersion, and the crystallites of cobalt
The relevance of the correct approach to the verification of modern electronic engine control systems of the car with regard to structural complexity, as well as the possibility of timely use of various diagnostic equipment to prevent engine failure, due to the timely detection of malfunction and reduce the costs associated with the operation and maintenance of road transport. The technology of diagnostics involves the mandatory verification of data received from the diagnostic system by measuring the corresponding physical parameters. The fault may be in the wires connecting the sensor and the control unit, in the control unit itself, in the connectors. To detect a fault, it is necessary to make a certain number of measurements of voltages, currents, and resistances and to establish the fault location using special diagnostic devices. On the basis of the obtained results, malfunctions of individual systems, assemblies, and aggregates are identified, then, taking into account indirect performance indicators, their technical condition is analyzed. In the end, it is possible to reliably assess the technical condition of the car, to detect and eliminate the causes of deviations from the norm.
Keywords: electronic control unit, car, engine, check, diagnostics
The parameters of the porous structure and the active surface of cobalt catalysts for Fischer-Tropsch synthesis (SFT) prepared by the impregnation method have been studied. Characteristics of composition and porous structure were studied using elemental analysis and the Brunauer-Emmett-Taylor method (BET). The effect of the addition of oxide promoters on the specific surface area, pore volume and pore size of the Co / SiO2 catalyst has been studied.
Keywords: Fischer-Tropsch synthesis, heterogeneous catalyst, promoter, carrier, specific surface area, porous structure, selectivity, activity, dipping method
The parameters of the porous structure and the outer surface of cobalt catalysts for the synthesis of Fischer-Tropsch, promoted by magnesium, prepared by the impregnation method according to moisture capacity, were studied. The effect of polymorphic modification (γ, θ, α) of the carrier on the physicochemical properties of the catalyst Co-Mg / Al2O3 was studied.
Keywords: Fischer-Tropsch synthesis, polymorphic modifications of Al2O3, synthetic motor fuel, catalyst, carrier, elemental analysis, BET method, specific surface, porous structure
The dependence of influence of size of a bend on tensely strained state of load-bearing frames of a covering is analysed. On the basis of the received results the maximum corner of a bend of the metal corners reducing a carrying capacity of farms is defined.
Keywords: a rafter farm, bend, tensely strained state, a moment of inertia, a radius of gyration, a barycentre
Three batches of Co-MxOy / SiO2 catalysts were prepared with different methods of introducing an oxide additive. Physicochemical studies of catalysts by elemental analysis and Brunauer-Emmett-Taylor (BET) methods have been carried out. The effect of additives of oxide promoters and the method of their introduction on the specific surface, volume and pore sizes for Fischer-Tropsch synthesis catalysts were studied.
Keywords: Fischer-Tropsch synthesis, carbon-containing resources, catalyst, active component, silicate carrier, Al2O3 and ZrO2 promoters, elemental analysis, BET method, surface area, volume and pore size