The article discusses the constructive and conceptual solutions associated with the implementation of the main devices of the central air conditioner, working in conjunction with the chiller. The peculiarity of the implementation of these devices is dictated by the use of solar energy. The receivers of solar energy are solar collectors, in which the heating medium is heated, which is used as a heat source in the chiller generator.
Keywords: solar energy, central air conditioner, chiller, absorption refrigeration machines, vacuum solar collector
Various options for connecting wooden structures are described. Examples of the use of various compounds, the most common today, are described. The advantages and disadvantages of such compounds are analyzed, and the technical characteristics of the elements used are given. Advantages and disadvantages of joints of wooden structures with the use of composite materials are described.
Keywords: wooden structures, joints of wooden structures, analysis, mechanical connections, comparison, load, strength, nagel, cool connection, mating, toothed plates
The article investigates the role of the preparation method and heat treatment in the formation of the physicochemical properties of cobalt catalysts on ZSM-5 support. Determination of the main characteristics of the samples showed that the Co/ZSM-5 I catalyst obtained by the impregnation method has the optimal cobalt dispersion and crystallite size.
Keywords: synthesis of hydrocarbons, cobalt, zeolite, preparation of catalysts, heat treatment
It is indicated in the article that the study of the electron bunching process in the drift space of a transit klystron is an urgent task that allows one to establish general laws applicable to more complex models. In this connection, the behavior of the pre-modulated electron beam in the drift space of the transit klystron has been investigated. A numerical model has been implemented that takes into account the effect of space charge fields and the interaction of charged particles with elements of an electrodynamic system. A series of numerical experiments with different values of the current and initial velocities of electrons, as well as their comparison with theoretical data, have been carried out. As a result of numerical experiments, data were obtained that characterize the dynamics of the electron flux in the drift space of the transit klystron at different values of the initial velocity (0.5 s, 0.9 s) and cathode current (10 mA, 1A, 10A).
Keywords: flyby klystron, mathematical model, numerical simulation, large particle method, particle-particle method, drift space, convection current distribution, electron flow, multithreaded calculations, system of differential equations
In the oil industry, autonomous electric power sources containing renewable energy sources are used to power remote consumers with an occasional load, mainly valve assemblies on pipelines. The need for electric energy sources of this type is determined by the need to install valve assemblies at pipeline intersections with water barriers, at intersections with transport arteries, and in a number of other cases. Very often in such places there are no available power lines or substations. In this case, the only alternative is the use of autonomous sources, or the expensive construction of an extended overhead line. In some cases, the developer decides to abandon the overhead line due to its high cost and the need for additional land acquisition. From the point of view of ecology, such a decision in favor of autonomous sources of electric energy also has an additional positive effect. Since the installation of valve assemblies is dictated mainly by environmental considerations, high requirements are placed on the reliability of power supply. Violation of these conditions can lead to hydraulic shocks in the system and possible destruction and breakage of system elements. A wind turbine or solar panels are undoubtedly an independent source of power supply and, when paired with batteries or a diesel generator set, can formally provide high reliability of power supply. On the other hand, there are periods of time when the power of a wind turbine or solar battery is insufficient to supply a given load. As a consequence, the decision on the reliability of power supply should be made on the basis of additional studies of the static and dynamic stability of the entire electrical power generation complex.
Keywords: renewable energy sources, valve assembly on pipelines, ecology, static stability, dynamic stability
For a decision maker, the problem is to choose the best franchise on a wide variety of existing Russian and foreign alternatives in the face of uncertainty. For a successful business, a decision maker needs to analyze the data on all the criteria among the selected franchises. In this paper, 5 alternatives- franchises of linguistic centers were considered. To calculate the weights of the importance of the criteria, the hierarchy analysis method was used. By fuzzy criteria using the Fuzzy VICOR method, a comparative analysis of several franchises was conducted. As a result, the best franchise for doing business was revealed. The Fuzzy VICOR method allows to get an effective result even in the conditions of uncertainty of input data.
Keywords: decision making, franchising, fuzzy decision making method, hierarchy analysis, defuzzification, Fuzzy VICOR
A model that implements a method for assessing the security of a special purpose automated information system is considered in the article. The model takes into account both the intensity of the load on the system and the number of channels as a means of protecting information from DDoS attacks based on the combination of theoretical and empirical approaches to assessing security of special purpose automated information system. The transition from a theoretical model using empirical states and continuous time to a discrete time model is applied to build a new model. The purpose of the work is to develop a model that implements a method for assessing the security of a special purpose automated information system against DDoS attacks based on a theoretical-empirical approach to modeling information protection means against DDoS attacks.The following tasks are solved in the article: analysis of known models that implement the method for assessing the security of special purpose automated information system from DDoS attacks; the model which implements a method for assessing the security of special purpose automated information system based on a theoretical-empirical approach to modeling information protection against DDoS attacks is being developed. The use of the new model makes it possible to apply both empirical values obtained as a result of measurements or modeling, and a theoretical basis for modeling information protection means under the influence of DDoS attacks, taking into account their characteristics, which will be reflected by the income function and the choice of the optimal mode of functioning of the special purpose automated information system in discrete moments in time. When synthesizing the models presented in the article, the lack of the static nature of the assessment of the security of the special purpose automated information system was eliminated, the intensity of computer attacks such as DDoS, which dynamically changes both the parameters evaluating the means of protection and the probability of the system being in critical states, was taken into account.
Keywords: automated system, modeling, security assessment, queuing system, probabilistic assessment, DDoS attack
The virtual simulator of the car inspector is considered. A distinctive feature of this project is that a visual programming editor was developed specifically for this simulator with a set of necessary functionality for developing other virtual simulators. The editor is designed for the Unity3D engine . The editor's functionality has been scaled and expanded, and new vertexes have been added to the developed system. The animation processing algorithm was used and new classes were created. The resulting vertexes are combined into a chain and their performance is checked.
Keywords: virtual simulator, visual programming editor, car inspector, Unity3D engine, Collider
The article deals with the problem of modeling an automated control system for the process of electroplating metal parts. The analysis of literature sources devoted to electroplating is carried out. The problem and process of electroplating metal parts with the use of reverse is considered. The calculated ratios are given to determine the required current (direct, reverse, increased, reversed), the process time and other internal parameters for the galvanization process. The possibility of performing current switching, setting its value and determining the process time, as well as reversing with the help of automation tools is considered on the example of the model. The model allows for given geometrical parameters galvanization details and preset thickness of the plating to calculate the basic control parameters of galvanization process: electroplating current and duration of the electroplating process. The electroplating process model is sensitive to the shape of the electroplated parts and the composition of the electrolyte, so the automated control system must perform model calculations for each type of parts and electrolyte. Graphs of simulation results in the SimInTech software environment obtained by drawing up a block diagram for a model of an automated control system for the process of galvanizing parts are presented.
Keywords: model, automated system, galvanic coating, geometric parameter, reverse
Recently, the issues of improving the environmental situation in the urban environment have become more relevant than ever. "Green architecture" gets popularity not only in Russia but over the world as well. The necessity of this type of architecture causes the need to improve air quality and environmental factors of urban conditions. Most often, greening the roof of a building or greening the facades is used for ecologization, so-called the element of wall greening and also greening of vertical surfaces of buildings (phyto facade).
Keywords: green architecture, vertical greening, green wall, waving plants, green screens, phyto facades
The article is devoted to improving the processing of radon flux density measurement data using mathematical processing. The article considers the influence of construction works on the radon flux density (RDP) indicators. for the purpose of the study, real measurements were taken at a mining and processing plant in the volgograd region. The article presents the construction of histograms and frequency polygons for measurements performed at different stages, as well as graphs of the empirical distribution function of a random variable. They clearly showed the impact of construction, the hypothesis of the influence of clay soils on the radon output from the soil was confirmed, namely, it was proved that the permeability of the near-surface layer of soil is one of the key factors determining the spatial PPR within homogeneous areas, that is, the permeability of near-surface deposits is one of the leading factors determining the distribution of PPR. analysis of the obtained results allows us to conclude that there is a correlation between the calculated data obtained and the data obtained at the measurement input, i.e. relationship of two or more random variables.
Keywords: radon, pollution, ionizing radiation, engineering surveys, random variable, histogram and frequency polygon, empirical distribution
Assessment of flexural strength is important in the design of steel beams. In this paper, analytical studies have been carried out to determine the flexural strength of conventional steel I-beams and steel corrugated beams. An experimental program was analyzed for four beams with a simple support and different web configurations (flat or corrugated) and different flange thicknesses (thin or thick). In the course of experimental work, the effect of a decrease in the bending capacity of a beam due to a corrugated web was determined. To simulate the tested samples and check the results of the experimental part of the work, a nonlinear finite element technique was used. After receiving the results, the following conclusions were made. First, the bending capacity of the corrugated steel beam is less than that of the conventional steel I-beam, in the range of 10 to 20%. Second, the flexure of the flat-web steel beam showed local buckling of the flange followed by local buckling of the web, in contrast to the steel girder with a corrugated web, which previously showed only local buckling of the flange. And third, the finite element model can simulate the behavior of steel beams, especially in the elastic stage, with an acceptable degree of accuracy.
Keywords: steel beam design, flexural strength, corrugated web, flange thickness, bending capacity, finite element technique, web configuration
Southern cities with hot and calm climate conditions, located on difficult terrain due to the lack of sufficient aeration, are in an extreme ecological situation. Urban construction on difficult terrain affects the established local microclimate by changing the structure of the environment and hydrogeological conditions. In addition, the development of urban space and the construction of modern multi-storey buildings significantly affect the aerodynamics of the environment and ecology. In the article, on the basis of the analysis of the climatic parameters of the cities of Sochi, Makhachkala and field observations, the conditions under which the local air circulation is formed, contributing to the improvement of the ecological situation, are revealed. Models of the formation of aeration of urban space for different types of landscaping have been constructed The analysis performed will make it possible to correctly assess the factors influencing the formation of aeration of thermal origin and their role in improving the ecology of cities with hot and calm climate conditions.
Keywords: wind, buildings, structures, landscaping, space, climate, region, analysis, landscape, aeration, ecology
On the territory of the Perm Region there are a large number of deposits of carbonate rocks. Their application in various industries is limited due to the high amount of impurities, so to expand the scope of application of local carbonate rocks, it is proposed to use chemical methods for obtaining deposited chalk, which were considered in the article. The most rational method seems to be the carbonation of calcium hydroxide with carbon dioxide. The implementation of this method is possible at commercial lime production plants, which will not only solve the important environmental problem of carbon dioxide emissions in such industries, but also will allow expanding the market for high-quality calcium carbonate, which is in demand by various industries.
Keywords: calcium carbonate, chemically precipitated chalk, lime, calcium oxide, calcium hydroxide, carbon dioxide, carbonation, commercial lime
The parameters of the mixers widely used in the practice of water treatment are given. A fundamentally new design of the mixing unit is proposed, which provides a process of rapid and complete mixing of reagents in a thin layer of a rotating flow of a pre-created water-air mixture using the method of concentrated coagulation. At the same time dispersion of air bubbles is carried out. A detailed description of the design, operating principle and basic design parameters of the mixer used in the mixing unit.
Keywords: natural water, coagulant, mixer, concentrated coagulation, aeration, velocity gradient, rotational motion
The results of the analysis of quality parameters of building materials used for insulation of walls of residential buildings are presented. The problem of increased consumption of thermal energy for heating needs is identified, the solution of which is to increase the thermal characteristics of the enclosing walls of buildings by means of their insulation and protection by the system of a hinged ventilated facade.
Keywords: Hinged ventilated facade, thermal characteristics, influencing factors, energy efficiency
Methods and results of determining indicators of deformation and strength properties of soils using various laboratory test technologies are considered. The research objective is to verify the methodological correctness of the results obtained from tests in a compression odometer chamber with the ability to measure lateral stresses. The relevance of this development lies in the possibility of replacing this device with testing to determine the strength characteristics of the soil in shear devices. The results of tests of fine sand lying at the base of the projected sports and recreation complex at one of the construction sites in Penza are presented. The influence of the used test methods on the obtained values of the strength and deformability characteristics is shown. Correlation indicators are revealed and corresponding conclusions and proposals are given. There is a possibility that the method is valid when some correlation coefficients are used. Therefore, in the future, it is necessary to conduct tests on different types of soils with the possible compilation of tables of conversion factors.
Keywords: sand, laboratory test methods; single-plane cut, odometric tests, strength characteristics, deformation characteristics
This article discusses the most common materials and how they are used to protect against ionizing radiation used for medical purposes. Comparison of technical and economic devices for the construction of a protective fence from the described radiation protection materials is presented. The effectiveness of the use of self-adhesive polymer radiation-shielding materials for protection against insulation with voltage up to 100 kV has been established.
Keywords: gamma radiation shielding, radiation shielding, EPDM, metal oxide, barite, polymer composites
The article discusses the causes of accidents in water supply and sanitation systems. methods for improving the quality of drinking water in the construction and reconstruction of water pipes, the use of new materials to reduce breakdowns on networks are considered. the analysis of the durability of pipelines made of various materials is carried out, according to which it is concluded which material is the best in use for installation work. frequent destruction of pipes occurs from an aggressive environment, so a comparative analysis of various materials from which they are made: polyvinyl chloride, polypropylene, reinforced concrete, cast iron and fiberglass. due to poor-quality cleaning, there are environmental problems that occur when using old structures, lack of funding. It is concluded that fiberglass pipes can serve as a high-quality material.
Keywords: quality water, replacement of pipelines, water supply and sanitation, corrosion and destruction of pipes, new polymer material, pipe materials, comparison of pipes made of different materials, service life, wastewater treatment, ecology
The article deals with the laws of distribution of pollutants in a linear city. The highest values of carbon monoxide concentration were determined in the near-main territories of the Krasnoarmeysky district of Volgograd. Also in this paper, the question of the dependence of the level of gas pollution in the mainline areas on various factors, which include human activity and natural, natural factors, is raised. The influence of temperature inversions on the speed of pollution propagation and their limiting value in various points of the city is considered. For the experimental part, 18 points of technical measurements of CO concentration were taken, during which compliance with the MPC standards of the samples taken was revealed.
Keywords: linear city, district, law of distribution of carbon monoxide, transport of impurities, air pollution