This paper presents a mathematical model and a geometric method of image-based object classification intended to improve the accuracy of object classification by filtering out noise objects.
Keywords: image processing, object recognition, pattern recognition, object identification, classification
At present, various software systems are widely used to carry out researches in the field of technology, make it possible to create mathematical models of real objects. Their further study allows to obtain a large amount of calculated data necessary for units’ design, resource assessment and performance of the object under study. This makes it possible to significantly reduce the conduct of experimental studies of real objects, as well as to obtain additional data that characterize specific parts during operation, such as the values of internal stresses, natural vibration frequencies, data on strength, fatigue, etc. However, during the process of real objects models creating, not always all the necessary data is available. In this regard, it is necessary to carry out research with some real details. To determine the material hardness of the rotor shaft of the turbocharger at different depths from the shaft surface, special new samples were made. Next, the microhardness of the material was determined. The hardness of the material from the surface decreases and at a depth of 1 mm becomes equal to the hardness of the unhardened one. After research finishing, a geometric model of the rotor shaft is created. The model is created using the SolidWorks Simulation complex. The working part of the shaft model consists of two layers: the first one is the surface with increased hardness and 1 mm thick; the second one is internal unhardened. This model is used in the research and development of technological processes for the repair of the part.
Keywords: software package, mathematical model, static analysis, rotor shaft, hardening, hardness, sample, depth, surface layer, repair
Polymer concrete is a concrete that uses polybutadiene, a polymer from the liquid rubber family, as a binder, so that it has elastic properties and is extremely resistant to aggressive chemicals, high water repellency and high compressive strength. It does not reveal the destruction typical for ordinary concrete, such as cracking and peeling. It has a high electrical resistance, increased mechanical compressive and tensile strength. In addition, polymer concrete is a durable material with water-repellent properties and resistance to aggressive chemical environments. The proposed polymer concrete uses a conventional aggregate, which is used to produce ordinary concrete, but a polymer is used as a binder. Also, the usage of non-metal composite reinforcement is proposed (APP patent No. 16983646). Below are the results of testing samples with three types of dispersed reinforcement.
Keywords: polymer concrete, rubber concrete, composites, fittings, manufacturing methods, testing
The aim of the study is to develop an "evolutionary model" of a transport interchange complex (TIC) - as a kind of ”growth point" of an aeropolis. Methods of “prognostic” and “structural-morphological” modeling of TIC are used for reasonable planning of the growth and development of the aeropolis. Five intermediate architectural and typological models of the transport and transfer complex have been identified: 1) bus station; 2) bus station with logistics center; 3) intermodal complex station; 4) transport and business center; 5) transport and public complex. Its "structural and morphological units", which include: a) functional components; b) structural and tectonic "units"; c) communication "framework"; d) elements of the growth of the aeropolis. A similar diachronic (developing) model of a transport interchange complex ensures its phased planning, optimal functional zoning of the facility for each intermediate phase, which will allow it to be self-sufficient at the early stages of operation. architecture.
Keywords: architecture, shaping, functioning, spatial development, transport interchange complex, transport interchange hub, transport infrastructure, aeropolis, model, structural and morphological approach, social and business center
the article analyzes the economic instruments used by states in domestic and foreign policy from the point of view of identifying the existing coercive mechanisms in modern social practices. The study revealed how states use economic instruments as the preferred means of geopolitical struggle. In addition, the work separately reflects the fact that States should preserve the right to an original socio-economic model of development. We should also not forget about the negative consequences of unilateral coercive measures. Using the method of cognitive modeling and constructing cognitive maps, the authors identify the connections in the analyzed social practices from the perspective of studying the means of geo-economic pressure.
Keywords: cyberwarfare, cyberattacks, cybersecurity risks, communication networks, transport systems, tactical, operational and strategic initiatives
Research in the field of design of buildings and structures has shown that the level of implementation of BIM technologies in different countries is at different levels. The availability of a regulatory framework in this area, financial assistance to construction organizations during the transition to BIM modeling contribute to raising the level. The article also provides a justification for the use of BIM technologies in ventilation systems, taking into account the requirements for these systems.
Keywords: BIM modeling, ventilation systems, 3D design, Autodesk Revit, implementation levels, information modeling, BIM technology, regulatory and technical base
The paper presents analytical estimates of the proximity of solutions to boundary value problems for elastic-creeping layered composite materials widely used in technology under long-term loading, and also gives the corresponding averaged model for such materials. The estimates show the possibility of using the averaged model over a long time interval for the problem of loading by a constantly acting force. Previously, this statement was confirmed by numerical experiments comparing solutions of boundary value problems for an effective (averaged) model and direct numerical calculation using the original model for a highly inhomogeneous layered material. Analytical estimates are based on previously obtained estimates of the proximity of solutions to stationary problems of elasticity theory. For the one-dimensional model considered in this work, the following property is established: if the constitutive relations for various phases of the composite material are written as dependences of deformations on stresses, then the coefficients for the same form of writing the constitutive relations of the averaged model are obtained as simple weighted average values of similar coefficients for individual phases.
Keywords: layered composite materials, creep theory, averaging method, evaluating the efficiency of the averaging method, asymptotically long time interval
This article is devoted to the study of indoor air quality in a higher education institution: assessment of the distribution patterns of suspended solids by equivalent diameters (RM0.5, RM1, RM2.5, RM5 and RM10).
Keywords: indoor air, indoor air quality, air pollution, dust, solid suspended particles, PM2.5, PM10
Modern trends of the concretes studies have been considered. Properties of the materials and additives used have been cited. There has been undertaken designing an experiment on a complex modifying additive application for a fine fibre-reinforced fine-sand cocrete. The results of the studies undertaken have been analyzed with regard to their statistical significance. On the bases of the reseach results there have been acquired regression equations for objective functions responses, namely ultimate strength on both compression and bending, and average density of fine fibre-reinforced concrete. There have been produced contour plots and those of response function surface - ultimate strength under compression for all combinations of the both factors. There have been determined the composition of the modifying additive, which ensures maximal strength properties for fine fibre-reinforced fine-sand concrete.
Keywords: fine concrete, complex additive, designing an experiment, strength, regression equation, plots of response function surface
In order for a person with an amputated limb to regain motor activity, should be created fitting lower limb prosthesis and able to movement. The goal of this research is to improve a passive prosthesis depending on microcontroller-unit, transfemoral prosthesis that can reach to the desired of rotational speed for functional use while remaining low-cost. The improvement of this design focuses on creating a new knee joint mechanism using a DC motor pre-existing, the foot, and the socket can get from the previous model. This entails simulating normal limb function while also enhancing the knee prosthesis range motion. the specific requirements that must be realize in this design, such as the knee joint new model ability to flex up to 90 degrees and be strong enough to support the weight of the amputee's body.
Keywords: knee joint, prosthetics, Solid works, ANSYS software, aluminum 6061-T6, stainless Steel 4130
The results of the automated evaluation of the dynamic quality of grinding machines in the process monitoring system are presented. The transfer function of the dynamic system is analytically obtained, a formula for the frequency function is derived from it, on the basis of which models of vibration spectra are constructed, in which frequencies are present that are adequate to the real vibro-acoustic vibrations of the dynamic system of the machine when processing rings. For experimental evaluation of the dynamic quality of machine tools, integral estimates of the low-frequency components of the vibration spectrum are used, characterizing the relationship between the quality of processing bearing rings and the dynamic quality of machine tools.
Keywords: dynamic quality of the grinding machine, vibroacoustic vibrations, bearing rings, processing quality, monitoring system
The study examines the manufacturing process of two types of ankle-foot orthoses (AFO): an adjustable joint and a modified static joint. Polypropylene and steel are used in manufacturing. Vacuum forming is used in the manufacturing process. The ankle orthosis test is performed on a patient with an ankle fracture as a result of a sports injury. The treadmill and F-Socket are used in the second step of the study for gait analysis. In addition, walking cycle results including: ground reaction force (GRF), center of pressure, pressure distribution, stride length, and footprint analysis were used to demonstrate a significant difference between healthy subjects and subjects with pathology who wore AFO. Interference, force, and pressure between feet with AFO contact areas were measured for all subjects.
Keywords: orthosis, ankle-foot orthosis, prosthetics, lower extremities, manufacturing procedure, subject with pathology, subject without pathology
The article describes the simulation in the Simulink environment of the operation of a stepper motor used as an electric drive of the scanning mechanism for the Earth orientation device. The purpose of the study is to determine the minimum power consumption in each range of values for inductance and resistance. If the model is found to be inoperable above certain values of the specified parameters, the measurement range narrows to an area where there is enough energy to properly work out a given angle. The simulation is based on the parameters of NEMA17 engines, in particular, NEMA 17HS3410. Voltage control in the system is carried out by means of a PI controller, the influence of the regulator on the energy consumption of the system is shown. The regularities of the formation of angular velocity of various amplitudes when working out a turn in open and closed control systems are noted. The range of electrical parameters at which the engine operates with almost the same power consumption is determined. The lowest power values at which the engine is operable are found. The results of the work are visualized in the form of three-dimensional surfaces, recommendations for the continuation of research are developed.
Keywords: stepper motor, simulation, Earth orientation device, power consumption
The development of technical devices in almost all industries is aimed at creating universal devices that allow performing several operations. The forest industry is no exception. The creation of a taxation tool that provides the ability to perform several measuring operations, which is the goal of the work, will increase the efficiency of the taxator while reducing the physical load on him due to the need to have fewer measuring instruments with him. All this indicates the relevance of this work. To achieve this goal, a number of tasks were solved in the course of the work, the main of which were: analysis of known designs of taxation instruments, synthesis of new technical solutions for their unification, patenting of a new technical solution. The use of system analysis made it possible to achieve the set goal, to propose a new patentable solution for a taxation device that combines the functions of an altimeter and a full gauge. The approach described in the paper to the creation of new designs of universal taxation devices can be used in teaching engineering creativity to students.
Keywords: full gauge, altimeter, taxation, forestry
Refrigerating machines are designed to cover peak heat generation in public buildings. At the same time, peak loads are often short-term and most of the time the refrigerating machines operate at 40-60% of their maximum capacity. The article deals with the issues of uneven cold consumption on the example of a sports complex located in Volgograd. When designing the air conditioning system of the games hall, a cooling system with the use of "chiller-fan coils"is used. An effective solution to reduce costs is to include a cold storage battery in the cooling station circuit. The use of a cold storage battery allows you to reduce operating costs.
Keywords: cooling system, air conditioning system, refrigeration machine, cold storage, energy consumption, peak loads, variable energy consumption