This article concentrates on the issues of radio wave propagation in forest conditions. The issue of representing the forest mass as a heterogeneous structure with a low dielectric constant is considered. Calculation and comparison of radio signal attenuation using several empirical models were carried out. It is shown that empirical models take into account the heterogeneous structure of the forest when moving from free space to the forest.
Keywords: radiowave propagation, wooded area, empirical model, radiowave attenuation, path loss, ground mobile communication, electrodynamic characteristics of a heterogeneous structure
The purpose of this study is to perform a classification to form a knowledge base in the field of harvesting and use in industry and in the social sphere of one of the valuable types of non-wood forest resources-tree greens. Such knowledge base is necessary for synthesis of new progressive processes, machines and mechanisms for harvesting and use of wood greens. The basis of the classification formation is based on the analysis of technological and technical solutions based on scientific and technical search, given in inventions and utility models patented in 2010-2019 in the Russian Federation. As a result of researches the main directions of patenting of developments in the field of preparation and use of wood greens are classified.
Keywords: modeling, wood density, logging, skidding, forwarder, skidder
Various methods are used to scatter warm fogs: direct combustion of fuel in the fog; electric heating of the fog; introduction of streams or jets of warm and dry air into the fog; use of radiant energy for direct evaporation of hydrometeors; using explosions of highly heat-forming substances, etc. [4]. In this paper, artificially sprayed water droplets are used to scatter warm fogs. Refined calculations were made to investigate the possibility of fog scattering by artificial droplets. The model describes the fall of drops of radius r2 through the fog, consisting of drops of radius r1, the concentration of which is equal to n1. Detailed equations of gravitational coagulation are used taking into account the hydrodynamic interaction of droplets. The temporal characteristics of fog scattering (increase in visibility range) depending on the size of artificial droplets and their concentration are investigated. The size of artificial drops and their concentration, at which the maximum effect on fog scattering is achieved, are determined.
Keywords: scattering of warm fogs, meteorological visibility range, concentration of fog drops, fog water content, artificial influence on fog
The paper presents the results of numerical estimates of scattering of a dispersed medium (fog) using thermal and dynamic devices. Numerical modeling methods were used to obtain the results. On the basis of calculations, the use of different classes of combustible substances (kerosene, etc.) was analyzed for thermal dispersion, which is based on heating the air-drop medium to a temperature above the dew point, so that the drops that make up the fog evaporated. Technical devices of various capacities for pumping air from the zone of illumination, that is, using the method of dynamic scattering, are considered. The dynamic method is based on creating a flow of dry air located above the dispersed medium layer. In this case, the drier air coming from above or from the side causes the particles of the dispersed medium to evaporate, which leads to a decrease in its density.
Keywords: dispersed medium, low layered clouds, thermal scattering method, dynamic scattering method, calorific value of substances, zone of enlightenment
The construction of social infrastructure is an integral part of improving the quality of life. The study systematized the main problems faced by the developer and the state in the construction of social infrastructure, provides an approximate list of measures that can improve the situation.
Keywords: social infrastructure, state, developer, economy, residential complex, public-private sector, housing construction, state, operation
Microelectromechnical system MEMS gyroscopes and accelerometers are using to measure the angular velocity of rotation and linear acceleration of an object, respectively. In many applications, the measurement of the angle is required, but gyroscopes have a mixing error that occurs when integrating the angular output velocity and the accelerometers have an error due to the translation force. This article presents a method for designing a complementary filter for estimating an angle using accelerometer and gyroscope and discusses the behavior of complementary filter in Matlab. As a results, the development of complementary filter system used to estimate the angle, can be used to consistenty and accurately improve the determination of the angle.
Keywords: accelerometer, gyroscope, complementary filter, MEMS microelectromechanical system
The influence of road transport on the formation of noise along highways is considered. The proposed options for protecting against noise from the roads.
Keywords: linear city, noise, vehicles, main roads, road categories, noise control
The authors propose to consider an interesting solution for finding real estate using GIS - technologies. This method can significantly reduce the time it takes to select a property. This article shows how the data processing capabilities of scientific computing tools for Python and the visualization and analysis capabilities of ArcGIS geospatial data can be used to build a model that generates a short list of houses that meet the needs and desires of potential buyers. And although the choice of a house is purely individual, there are a lot of common factors. Such as the total area, the number of floors and rooms, the presence of a garage and much more. Also, when buying a house, you are looking for proximity to services such as food, pharmacies, emergency rooms, child care facilities, parks, etc. You can use the ArcGIS API geocoding module for Python to search for such objects at a given distance around the house. This method suggests combining all the necessary conditions into one system, which will significantly reduce the list of real estate objects on the market and choose the most optimal options.
Keywords: GIS, ArcGIS, real estate, Python, maps, histograms, filter, DataFrame, spatial distribution, geocoding
The article proposes to consider the possibility of using pipes from ductile iron with spherical graphite in the construction of oil pipelines to solve the problem of corrosion formation. In addition to corrosion resistance, such pipes also have other positive properties. A comparison is made with steel pipes, and the basic physical and mechanical properties of ductile iron with spherical graphite are also considered.
Keywords: oil and gas pipeline, corrosion, testing, installation, connection, deposit, steel, ductile iron (ductile iron), strength, resistance, oil
The paper considers a game-theoretic model for supporting the distribution of labor resources, i.e. To simulate the problem considered in the work, the mathematical apparatus of game theory was used. In this paper, two algorithms for constructing a solution are described and examined in detail for two models of transport tasks used to study the distribution of labor resources: static and dynamic. The authors describe the developed models, and then consider the structure of the solution to the problem. The paper considers a compromise solution in the models of the distribution of labor resources for the transportation problem. An algorithm for finding a compromise set and a description of the structure of the software implementation of models is given. The description of the models is formalized in the field of application to game theory, i.e., a game version of the problem is considered. Interpreting the problem, we consider a system consisting of players. Players in the constructed model strive, in addition to maximizing profits, to achieve a compromise between the participants. The role of compromise will be played by a plan of movement of labor resources, satisfying all participants. As a result, we obtain the transportation problem in a slightly modified formulation. These differences specify a new task and set a goal to solve it.
Keywords: modeling, analysis, management, software implementation, game-theoretic models, distribution of labor resources
This article discusses logistics systems, problems existing in logistics, presents ways to solve these problems. The field of logistics includes almost all areas of production of each enterprise, such as commercial activities, transport management, information support and others. Construction enterprises should be most interested in the efficiency and rationality of the work of logistics, since it is one of the largest subjects of final consumption of material resources. However, there are logistics problems in the construction industry, but to avoid them it is necessary to understand the ways to solve them, which are described in this article.
Keywords: logistics, logistics system, construction industry, construction company, resource, integrated management, logistics problem
This article is devoted to the study of the problem of power supply of low-power consumers distributed along the path of electric Railways AC, which can act as a system of sensors diagnostics of automated control systems of various objects located along the contact network. The main part of the article is devoted to the description of the primary model necessary for further consideration of such a method of electric power supply and experimental modeling.
Keywords: contactless power transmission, capacitive communication, power supply, contact network, electric Railways
Fiber-optic data transmission lines (FOCL) are one of the main parts of automated data transmission control system, which controls technological processes of railway transportation. The lines are subject to powerful electromagnetic effects from traction power supply system. Improving the reliability of the entire system by reducing the electromagnetic influence and the optimal choice of the VOC location is a complex and urgent task, the solution of which will significantly improve the reliability and efficiency of the entire automated complex.
Keywords: Fiber optic communication line (FOCL), automated system, electromagnetic influence, system of equations
The article discusses the results of the calculation of monolithic non-slab floors. The authors used software that supports BIM design technology. Models were created in Rewit Sapphire and Lyra-SAPR. The article describes the method of creating computer models. The computational experiment plan and the main parameters of the calculated prototypes are given. A total of four series of samples was calculated. The series differ in the way they create a computer model. In each series, all methods of triangulation that are available for this software package are implemented. To ensure the comparability of results, the step of triangulation in each of the series was taken to be the same: 0.17, 024, 0.4, 0.46, 0.55, 0.67 and 0.86 m. The authors made a comparative analysis of the quality of computer models after they were imported into the PC Lira-SAPR. It has been established that errors are observed when importing schemes from different software systems. Characteristics of the material, the stiffness of the elements and the load are not always transmitted correctly. This circumstance forces to do additional work. Namely, a detailed check of the circuit and its adjustment manually. BIM technology, reinforced concrete, girder-free overlap, reinforcement, triangulation, finite element, reinforcement selection, computational experiment, Rewit, Sapphire, Lira-CAD.
Keywords: BIM technology, reinforced concrete, girder-free overlap, reinforcement, triangulation, finite element, reinforcement selection, computational experiment, Rewit, Sapphire, Lira-CAD
The problem of increasing the efficiency of compiling test plans when testing complex software systems is considered. Automation tools for the development of test plans allow us to describe this document in a rather generalized way, without taking into account many of the attributes required for the success of the further stages of testing the software systems. The use of the developed automated system (AS), described in the article, allows to reduce the complexity of creating test plans due to the presence of a clear sequence of steps in the preparation of the document, providing the specialist with background information and advising effects. In the future, this AS can be used both directly in the development of test plans in the course of real software projects, and in training novice specialists in the skills of filling out these documents.
Keywords: software testing, test plan, automated system