The article presents calculation of the cost of overlappings from LSTK and wooden ones. The floors of the two-storey house with a span and overlap with a span of 12 m were calculated. Calculation of the cost of materials is presented for each option. In conclusion, conclusions were drawn on the rational use of material types for each of the calculated spans.
Keywords: light steel thin-walled structures, LSTK ceiling, wooden flooring, reduced characteristics, effective cross-section, construction
The possibility of revealing the main defects that arise when strengthening reinforced concrete structures by external reinforcement systems based on carbon fibers is considered. The efficiency of active and passive methods of thermography is compared, and the possibility of using the passive method at negative ambient temperatures is considered. Under laboratory conditions, ferroconcrete samples with defects in the form of air bubbles and glue were made and a comparison of the mapping of these defects on thermograms was made.
Keywords: composite materials, reinforcement, external reinforcement systems, infrared thermography, defect, work quality assessment, technical condition assessment, span structures, bridge supports
The use of modern innovative control systems for heat supply in the housing and communal services is the task of today. Within the framework of the program of energy-saving technologies, an automated system for monitoring and controlling the parameters of the coolant in the housing and communal services is proposed. The proposed system is based on industrial controllers with Ethernet 100 Base-T, RS-232 and RS-485 interfaces and software created in the freely distributed version of the Owen CoDeSys package.
Keywords: shut-off valve, shut-off and control valves, CoDeSys, proportional-integral-differentiating controller, pipeline fittings
The system analysis of the main directions of the fourth scientific and technological revolution, called "Industry 4.0" in the field of road transport, is conducted in the article. The essence of the industry 4.0 is the development of the digital economy using cyberphysical systems, the Internet of things and large data. Applicable to road transport can be identified three areas: the creation of an unmanned vehicle, the development of technological support for the movement of trucks in the convoy, the development and implementation of "automobile Internet". At the same time, there are a number of technological, legal and ethical problems that hamper the large-scale development of a new generation of transport.
Keywords: Industry 4.0, unmanned vehicle, Internet of Things, Cyberphysical systems, autonomous transport, cloud technologies
Stable operation of computer equipment is important for its effective use. A significant role in ensuring stability depends on the reliability of the software. The article analyzes the state of the problem to improve the reliability of the software based on the models of reliability assessment. The methods of increasing the software reliability using time and software redundancy are analyzed. It is concluded that there is no universal solution to the problem of software reliability in the presence of many private solutions.
Keywords: software reliability, software reliability evaluation models, classification of software reliability models, methods of software reliability improvement
An approach to real time modeling of automotive FMCW radar performance in autonomous driving applications is proposed. Simplified model of driving situation and model of reflected signal are developed on the basis of commercial automotive radar performance. Complex solution for radar sensing modeling was produced. Modeling results are represented.
Keywords: autonomous car, computer vision system, modeling, automotive radar, scattering centre, Fourier transform, radar image
The processes of extraction and processing of oil and oil products are accompanied by negative consequences at the level of the environment in the form of accidents. They act both on the water area and on land. This article is devoted to the liquidation of emergency oil and oil products spills with the help of natural sorbents. For the analysis, three readily available materials were taken in the national economy of the Russian Federation: wool, wheat straw and sawdust. The main indicative value for the sorbent is its oil capacity (sorption capacity) the amount of absorbed oil, which depends on the degree of specific surface of the material. The higher the specific surface area, the higher the sorption capacity. To determine the oil capacity, each of the materials was placed on a flat surface and artificially contaminated with oil for one hour. During the experiment, the absorbent capacity of the sorbents was determined, which for each proved to be different. Based on the data, graphs are constructed that clearly show the applicability of a material.
Keywords: Oil, oil products, extraction, oil consumption, material, sorbent, absorption, adsorption, accident, liquidation
In article the UAV three-dimensional mathematical model on the basis of the quadcopter as most the UAV widespread type at the moment is developed. The quadcopter is based on a frame of DJI F-450. The first part of article is devoted to the mathematical description of the quadrotor model, namely: to a kinematics and dynamics models; to forces and torques operating on the UAV; to rotation matrixes; to the assumptions simplifying mathematical expressions. For the description of location and movement of the quadrotor in space also the bound will be used inertial reference frame. Therefore transformation from one frame to another is necessary. The simulation of the operation of the motors 1-4, which are electric drives of direct current, has been performed. Rotation of engines is transferred to screws directly. Movement of the quadcopter in the bound frame is considered in the article by the accounting of the models of a kinematics and dynamics describing the vehicle movement.
Keywords: quadrotor, UAV, kinematics, dynamics, 3D environment, DJI F-450, engine, traction, rotation matrix, vehicle
The analysis of research on the separation of rice seeds on new types of polymeric sieves showed the absence of regularities that provide the studied processes. There are no dependencies describing the effect of the kinematic parameters of the operation of the sieves on the intensity of the separation processes of rice seeds. We performed a system analysis of the sieves with different types of holes. In the work, mathematical dependences between the amplitude and frequency of oscillations are determined for swinging polymer sieves.
Keywords: Rice seeds, polymer sieves, separation process, grating mill, kinematic parameters, mathematical dependencies
The relevance of modeling, design of digital devices and further synthesis of it on FPGA are substantiated in this article. This approach is demonstrated by example of microprocessor with famous architecture MIPS on the VHDL language. The further modeling, synthesis on FPGA by Altera and test on the specific example confirm the opportunity of prototyping real digital devices with the introduсed method.
Keywords: microprocessor, test, programmable logic integrated circuit, digital device, verification, model, hardware description language, field-programmable gate array,pipeline ,MIPS
To produce controlled radio frequency and microwave devices such as phased antenna arrays, delay lines, an affordable and inexpensive way of manufacturing varactors in large quantities should be found. One of the promising ways to produce such varactors is based on the use of a BST-paste with a low firing temperature, which allows it to be integrated into a substrate of low-temperature co-fired ceramics (LTCC).
Keywords: semiconductor, ferroelectric, BST-paste, ferroelectric condenser, LTCC technology
This article raises the problem of energy conservation of limited resources, provides an analysis of the most popular energy-efficient measures, presents examples of energy-efficient equipment, and discusses the problem of implementing energy-efficient solutions in the repair and construction industry in the Russian Federation at the present time.
Keywords: Energy saving, energy efficiency, energy resources, energy-efficient measures, energy-efficient technologies, energy-efficient
The parameters of the porous structure and the active surface of cobalt catalysts for the synthesis of liquid and solid hydrocarbons (Fischer-Tropsch synthesis) prepared by the method of impregnating a silicate carrier were studied. The effect of additives of oxide promoters on the specific surface, the volume and size of pores, the dispersion and size of crystallites of metallic cobalt on the surface of the Co / SiO2 catalyst was studied.
Keywords: Fischer-Tropsch synthesis, motor fuel, synthetic hydrocarbons, catalyst, promoter, carrier, specific surface, porous structure, catalytic activity, selectivity
In this paper the method of electrochemical oxidation/dispersion of zinc using pulse alternating current with average density of 0.2:1.2 A/cm2 was used. The mixture of ZnO and Zn5(OH)8Cl2·H2O (simonkolleite) was obtained. The application of this product as a photocatalyst provides a practically full removal of methylene blue dye under UV light. When the sample is calcined at 400 °С the decomposition of simonkolleite with a ZnO formation occurs. It is accompanied by decrease in surface area and photocatalytic activity of the material.
Keywords: zinc oxide, nanoparticle, simonkolleite, pulse alternating current, morphology, photocatalysis, methylene blue
The article presents a comprehensive analysis of emission indicators from stationary sources and emissions from motor vehicles in the Rostov region and the city of Rostov-on-Don, as well as a comparative analysis for the two regions of the Southern Federal District. The forecast of the ecological situation is made and the adequacy of the proposed mathematical model is checked.
Keywords: emissions of pollutants, toxicity, exhaust gases, stationary sources, auto transport, internal combustion engine